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The additive/subtractive hybrid manufacturing (ASHM) method, which takes the advantages of both additive manufacturing (AM) and precision subtractive machining (SM), is a promising technique for the surface quality improvement of an AMed part. However, machining characteristics and the residual stress evolution during the ASHM process have not been investigated in detail for the materials with phase transformation. In this study, an experimental study is conducted on manufacturing of a 6511 martensitic stainless steel with the ASHM method that combines selective laser melting (SLM) and end milling. The process window of SLM is determined in terms of the relative density. Milling forces, surface roughness, and residual stress of the ASHM samples with different cutting parameters are studied. The phase transformation of the martensitic steel is considered in the analysis of the residual stress. It is found that the surface residual stress state and distribution can be controlled by the milling parameters. This study provides guidance for the optimization of the process parameters for ASHM to manufacture martensitic stainless steel.

BackgroundBacterial proliferation on the endosseous implants surface presents a new threat to the using of the bone implants. Unfortunately, there is no effective constructed antibacterial coating which is bacterial anti-adhesion substrate-independent or have long-term biofilm inhibition functions.MethodsDrug release effect was tested in Chymotrypsin (CMS) solution andS. aureus. We used bacterial inhibition rate assays and protein leakage experiment to analyze the in vitro antibacterial effect of (Montmorillonite/Poly-l-lysine-Chlorhexidine)10[(MMT/PLL-CHX)10] multilayer film. We used the CCK-8 assay to analyze the effect of (MMT/PLL-CHX)10multilayer films on the growth and proliferation of rat osteoblasts. Rat orthopaedic implant-related infections model was constructed to test the antimicrobial activity effect of (MMT/PLL-CHX)10multilayer films in vivo.ResultsIn this study, the (MMT/PLL-CHX)10multilayer films structure were progressively degraded and showed well concentration-dependent degradation characteristics following incubation withStaphylococcus aureusand CMS solution. Bacterial inhibition rate assays and protein leakage experiment showed high levels of bactericidal activity. While the CCK-8 analysis proved that the (MMT/PLL-CHX)10multilayer films possess perfect biocompatibility. It is somewhat encouraging that in the in vivo antibacterial tests, the K-wires coated with (MMT/PLL-CHX)10multilayer films showed lower infections incidence and inflammation than the unmodified group, and all parameters are close to SHAM group.Conclusion(MMT/PLL-CHX)10multilayer films provides a potential therapeutic method for orthopaedic implant-related infections.

The corrosion behavior of nickel-based 718 alloy at seven partial pressures of H2S $$\left( {P_{{{\text{H}}_{2} {\text{S}}}} } \right)$$ was investigated using electrochemical impedance spectroscopy (EIS) and polarization methods in 25 wt% NaCl solution at 150 °C for 168 h. The tested results show that anodic reactions are controlled alternately by the diffusion mostly, then both charge transfer and diffusion and finally charge transfer mainly with the increment of $$P_{{{\text{H}}_{2} {\text{S}}}}$$ . The corrosive products are composed of sulfides and oxides of Ni, Cr and Fe with double layers for $$P_{{{\text{H}}_{2} {\text{S}}}}$$ of 5.1 and 13.0 MPa and three layers for $$P_{{{\text{H}}_{2} {\text{S}}}}$$ of 10.4 MPa according to microstructures and compositions of corrosion products characterized by the scanning electron microscope (SEM) and electron probe microanalysis (EPMA) methods. The inner oxides layer plays a critical role in anti-corrosion in a wet H2S environment at high temperature and pressure.

Due to the significant difference between the reinforcement grains and matrix phase, the machining of SiC particle-reinforced aluminum composites (SiCp/Al) is difficult and costly, especially for SiCp/Al with volume fraction higher than 50%. Ultrasonically assisted grinding (UAG), which has unique advantages in the machining of both ductile and brittle materials, is a promising solution of the machining of SiCp/Al. This study conducts both UAG and conventional grinding (CG) process on SiCp/Al with an electroplated diamond wheel. The study explores material removal mechanisms involved in UAG in comparison to that in the CG. It also investigates grinding forces, surface integrity, subsurface damage, and wheel wear. The study finds that material removal in grinding of SiCp/Al is dominated by SiC particle fracture that is induced in the grinding process. The ground workpiece is smeared with an aluminum layer, making it difficult to evaluate surface integrity. Compared with CG, UAG of SiCp/Al results in similar surface integrity in terms of surface roughness and subsurface damage, but a much lower grinding force (35–50% lower).

A highly stable hydrophobic Ba2SiO4:Eu2+ (BSO) phosphor was produced by forming a robust hydrophobic inorganic silicon-oxy-imide-carbide layer on its surface. The process for developing this layer involved coating, ammonolysis, and pyrolysis of chlorosilane. The tightly adhered coating layer had a lotus, leaf-like micro- and nanohierarchical structure and contained CH3 groups, which enhanced the hydrophobicity of the modified phosphor significantly. The modified phosphors treated at 500 °C exhibited remarkable stability in their emission spectra, even after exposure to high-pressure water steam at 100 °C for 48 h, which is attributed to the high stability of the surface layer.

In his research, a modified Dynamic Causal Diagram (DCD) based process operating performance optimality assessment and non-optimal cause identification method is proposed to handle the online assessment of the complicated chemical processes, where certainties and uncertainties coexist. In addition, the multi-source information usage problem of the traditional DCD is addressed. In the online application, a newly developed scheme is developed, which distinguishes stable performance grade and grades switch transition. For the non-optimal performances, a contribution based root cause identification method is developed, on the framework of the constructed DCD. Finally, the operating performance of a gold hydrometallurgy process is assessed by both the traditional DCD and the modified DCD. The superiority on accuracy and robustness of the modified DCD is demonstrated, and the responsible events for non-optimality is successfully isolated by the proposed contribution based non-optimal cause identification technique.

Hammerstein nonlinear systems have appeared useful in modeling nonlinear processes encountered in engineering practice. Control algorithms may lead to unsatisfactory performance if the parametric model does not agree with the plant. To this end, this paper proposes a new robust adaptive control approach for discrete-time Hammerstein nonlinear systems which are more close to some industrial plants. The adaptive control law and recursive parameter estimation are updated by introducing the estimate of the model error as a feedback. Theoretical results show that parameter estimation convergence and closed-loop system stability can be guaranteed under mild conditions. Simulation examples including a continuous stirred tank reactor (CSTR) system are given to show the effectiveness of the obtained results.

A novel approach of high-performance grinding is proposed using developed diamond wheels, to obtain minimally damaged surface layer in silicon wafers. For this reason, resin bond diamond wheels are specifically developed with lanthanum oxide (La2O3), magnesium oxide (MgO), and ceria (CeO2) as additives, respectively. The wheels contain grains with a mesh number of 20,000 and a volume fraction of diamond grains of 37.5%. The diamond wheel with ceria additives demonstrates the best grinding performance in terms of surface integrity and roughness. It allows to generate an amorphous surface layer of 43 nm in thickness, without grinding damage beneath in a silicon wafer. This is different from previous reports, in which an amorphous layer is at the top, followed by a damaged crystalline layer underneath induced by a diamond wheel. Below the amorphous layer is the pristine crystalline lattice, which is confirmed using the high-resolution transmission electron microscopy (HRTEM). The ceria wheel results in a surface roughness R a of 0.88 nm and a peak-to-valley (PV) value of 8.3 nm over an area of 70 × 50 μm2 on a Si wafer at a feed rate of 15 μm/min.

Diamond grit is widely used in cutting, grinding, and polishing tools for its superior mechanical properties and performance in machining hard materials. Selective laser brazing (SLB) of diamond grits is a new additive manufacturing technique that has great potential to fabricate the next generation of high-performance diamond tools. However, fundamental understanding and quantitative analysis for the design and tuning of the SLB process and the resulting bonding efficiency are not yet established as the process is complicated by heating, fusion, wetting, solidification, grit migration, bonding, reaction, and the interplay between these effects. We present a thermodynamically consistent phase-field theoretical model for the prediction of melting and wetting of SLB on diamond grits using a powder-based additive manufacturing technique. The melting dynamics is driven by laser heating in a chamber filled with argon gas and is coupled with the motion of multiple three-phase contact lines. The relevant wetting dynamics, interfacial morphology, and temperature distribution are computationally resolved in a simplified 2D configuration., Comment: 37 pages, 9 figures

Mercury released from wet flue gas desulfurization (WFGD) devices can be inhibited by additives that can transfer mercury to its solid phase. However, the use of additives increases the mercury content in desulfurization gypsum, and the mercury is released again during the calcination process. In this study, NaHS, 2,4,6-trimercaptotiazine, trisodium salt nonahydrate (Na 3 (C 3 N 3 S 3 )·9H 2 O, or TMT) and sodium dithiocarbamate (DTCR) were used as additives to control mercury emissions in simulated WFGD devices. Then, different calcination methods were adopted to study mercury release behaviors from calcination process. The transformation of mercury compound species on gypsum was also investigated to explain its behavior during calcination. The result showed that the mercury content in the solid phase increased significantly in the presence of additives. Among three additives, simulated desulfurization slurry with TMT had the highest trapping efficiency over mercury. The mercury thermal stability in gypsum increased in the order of using DTCR, TMT and NaHS. Due to the migration of mercury to the solid phase and the stronger thermal stability of resultants, the residual content of mercury in gypsum with additives after calcination were higher than that without additives. In general, using TMT coupled with slow-speed calcination had the best effect on controlling mercury contamination from WFGD slurry and WFGD byproducts. Moreover, it was verified by temperature programmed decomposition experiments that, after using NaHS, TMT and DTCR, the mercury compound in the gypsum was mainly in the form of HgS, Hg 3 (TMT) 2 , Hg(DTCR) 2 , respectively, which explained the mercury release behaviors during calcination.

As a new technology of reducing thickness of an aircraft skin, the mirror-milling system is widely used. The objective of this study is to optimize the support location in mirror-milling of aircraft skins. The study analyzes the machining mechanisms of mirror-milling system and establishes a theoretical model to predict the milling forces. In addition, it develops a finite element model to simulate workpiece deformation so as to predict workpiece profiles in mirror-milling system. The results of the study show that with the optimized support location, the profile error of the workpiece is reduced by 73.5%, whereas machining efficiency is increased.

Deformation nanotwinning is performed using molecular dynamics (MD) on a single crystal in a ternary nickel (Ni) alloy. Generalized embedded-atom method (EAM) potential functions are obtained for the ternary Ni alloy. The critical twinning stress is 4.48 GPa, calculated by the MD simulations. Detwinning, restoring and regenerating of nanotwins take place during the unloading process, contributing to the remaining of the ductility. According to the MD simulations, a novel approach is proposed to fabricating a nanotwinned surface using nanoindentation at room temperature. This is different from previous reports, in which high temperature, high pressure or chemical regents are employed. Keywords: Molecular dynamics, Nanotwinning, Nanotwinned surface, Transmission electron microscopy, Ternary nickel alloy

The error motions of micro mechanical systems, such as micro-spindles, increase with the increasing of the rotational speed, which not only decreases the rotational accuracy, but also promotes instability and limits the maximum operational speed. One effective way to deal with it is to use micro-flexible couplings between the drive and driven shafts so as to reduce error motions of the driven shaft. But the conventional couplings, such as diaphragm couplings, elastomeric couplings, bellows couplings, and grooved couplings, etc, cannot be directly used because of their large and complicated structures. This study presents a novel micro-coupling that consists of a flexible coupling and a shape memory alloy (SMA)-based clamp for micro mechanical systems. It is monolithic and can be directly machined from a shaft. The study performs design optimization and provides manufacturing considerations, including thermo-mechanical training of the SMA ring for the desired Two-Way-Shape-Memory effect (TWSMe). A prototype micro-coupling and a prototype micro-spindle using the proposed coupling are fabricated and tested. The testing results show that the prototype micro-coupling can bear a torque of above 5 N • mm and an axial force of 8.5 N and be fitted with an SMA ring for clamping action at room temperature (15 °C) and unclamping action below–5 °C. At the same time, the prototype micro-coupling can work at a rotational speed of above 200 kr/min with the application to a high-speed precision micro-spindle. Moreover, the radial runout error of the artifact, as a substitute for the micro-tool, is less than 3 μm while that of turbine shaft is above 7 μm. It can be concluded that the micro-coupling successfully accommodates misalignment errors of the prototype micro-spindle. This research proposes a micro-coupling which is featured with an SMA ring, and it is designed to clamp two shafts, and has smooth transmission, simple assembly, compact structure, zero-maintenance and balanced motions.

In order to improve machining efficiency of sapphire wafer machining using the conventional loose abrasive process, fixed-abrasive diamond plates are investigated in this study for sapphire wafer grinding. Four vitrified bond diamond plates of different grain sizes (40 µm, 20 µm, 7 µm, and 2.5 µm) are developed and evaluated for grinding performance including surface roughness, surface topography, surface and subsurface damage, and material removal rate (MRR) of sapphire wafers. The material removal mechanisms, wafer surface finish, and quality of the diamond plates are also compared and discussed. The experiment results demonstrate that the surface material is removed in brittle mode when sapphire wafers are ground by the diamond plates with a grain size of 40 µm and 20 µm, and in ductile mode when that are ground by the diamond plates of grain sizes of 7 µm and 2.5 µm. The highest MRR value of 145.7 µm/min is acquired with the diamond plate with an abrasive size of 40 µm and the lowest surface roughness...

This study proposes a polarized laser scattering (PLS) method for detection of the two-dimensional distribution of the grinding-induced subsurface damage (SSD). This study also uses two destructive methods to observe the distribution of SSD in the ground silicon wafers by cross-sectional microscopy and by layer-by-layer microscopy. An experimental investigation is arranged for detecting the two-dimensional damage from diamond wheel grinding of silicon wafers through wafer sample preparation and SSD observations with the cross-sectional and layer-by-layer microcopy. It also includes PLS detection of the ground silicon wafers for SSD information. The results show that both the depth of SSD and the crack density contribute to the PLS detection signals. The study reveals the characteristics of the PLS detection, which illustrates the potential application of the PLS method to in-process detection.

The eco-environmental quality assessment is a complexity of fuzzy system with multiple indicators and classes, and there are still some limits of radial basis function network evaluation method, so radial basis function network and particle swarm optimization algorithm are combined to establish an improved radial basis function network comprehensive evaluation method for eco-environmental quality assessment. Main limits of radial basis function network are how to choose parameter in the model, so in this method, through optimizing the parameters of the radial basis function by particle swarm optimization algorithm, a neural network model of regional ecological environment is generated to enhance the performance. Additionally, a visualization system of the ecological quality assessment is developed using ArcGIS software, which can be used to display and evaluate the ecological quality of eco-environmental quality. The eco-environmental quality assessment in Sichuan Province of China is taken as an example, and the results show that radial basis function network optimized by PSO is superior to the traditional model, GIS can inquire and display the message and evaluation results, and the hybrid method provides a new approach for the protection and scientific management of ecological quality and worth to be recommended.

Ceramic is an important material with outstanding physical properties whereas impurities and porosities generated by traditional manufacturing methods limits its further industrial applications. In order to solve this problem, direct fabrication of Al2O3 ceramic structures is conducted by laser engineered net shaping system and pure ceramic powders. Grain refinement strengthening method by doping ZrO2 and dispersion strengthening method by doping SiC are proposed to suppress cracks in fabricating Al2O3 structure. Phase compositions, microstructures as well as mechanical properties of fabricated specimens are then analyzed. The results show that the proposed two methods are effective in suppressing cracks and structures of single-bead wall, arc and cylinder ring are successfully deposited. Stable phase of α-Al2O3 and t-ZrO2 are obtained in the fabricated specimens. Micro-hardness higher than 1700 HV are also achieved for both Al2O3 and Al2O3/ZrO2, which are resulted from fine directional crystals generated by the melting-solidification process. Results presented indicate that additive manufacturing is a very attractive technique for the production of high-performance ceramic structures in a single step.

In this paper, multi-objective particle swarm optimization with preference information (MOPSO-PI) has been proposed. In the proposed algorithm, the information entropy is employed for measuring the probability distribution of particles; the user's preference information is represented as the ranking of each particle through the possible matrix. The optimal procedure is guided by the preference information since the global best performance of particle is randomly chosen among non-dominated solutions with higher ranking value in each iteration. Finally, the MOPSO-PI is applied to optimize the steelmaking process; the power supply curve obtained reduces the electric energy consumption, shortens the smelting time and prolongs the lifespan of the furnace lining. The application results show the effectiveness of the proposed algorithm.

Steel industry is an important part of the national economy, however, the complex process of ironmaking-steelmaking has been a serious constraint to the development of steel enterprises. In this paper, on the basis of the traditional processes of iron-steel interface, the planning of short process of iron-steel interface with “One open ladle” is proposed. There is also the design of MES in iron district, which has been applied in a steel enterprise of Chongqing, China, with significant effects.

This study investigates diamond scratching at a high speed comparable to that in a grinding process on an ultraprecision grinder. Diamond tips are prepared for the study. The scratched silicon wafer is observed for changes in the surface layer with transmission electron microscopy. The observation discovers that an amorphous layer is formed on top of the pristine Si-I phase before the onset of chip formation. This discovery is different from the previous findings in which a damaged silicon layer is identified underneath the amorphous layer. Furthermore, no high pressure phase is found before the onset of chip formation.

The Kalman filter has been widely applied in the field of dynamic navigation and positioning. However, its performance will be degraded in the presence of significant model errors and uncertain interferences. In the literature, the fading filter was proposed to control the influences of the model errors, and the H-infinity filter can be adopted to address the uncertainties by minimizing the estimation error in the worst case. In this paper, a new multiple fading factor, suitable for the Global Positioning System (GPS) and the Inertial Navigation System (INS) integrated navigation system, is proposed based on the optimization of the filter, and a comprehensive filtering algorithm is constructed by integrating the advantages of the H-infinity filter and the proposed multiple fading filter. Measurement data of the GPS/INS integrated navigation system are collected under actual conditions. Stability and robustness of the proposed filtering algorithm are tested with various experiments and contrastive analysis are performed with the measurement data. Results demonstrate that both the filter divergence and the influences of outliers are restrained effectively with the proposed filtering algorithm, and precision of the filtering results are improved simultaneously.

This study presents the design and evaluation of a high-speed and precision microspindle used for micromechanical machining. A radial impulse turbine with two rows of nozzles was designed to realize the high-speed performance. A monolithic flexible coupling was used to decouple the turbine shaft and the tool, and then, the tool shank was directly supported by aerostatic bearings, which can minimize the run-out of the tool at high speeds. Additionally, a shape memory alloy (SMA)-based clamp was designed for tool clamping. It can avoid the assembly error caused by stack-up tolerances. The microspindle has simple configuration and compact design with a 30-mm outer diameter and a 95-mm length. The prototype microspindle has a maximum speed of over 240,000 rpm and a tool radial run-out of 2.79 μm. The evaluation results show the feasibility and potential application of the new design concept of the microspindle proposed in this study.

For the bulk amorphous Fe24+xCo24-xCr15Mo14C15B6Y2(X=0, 2, 4, 6 and 17) alloy, the corresponding corrosion properties associated with glass forming ability (GFA) have been carried out. Neutral salt spray corrosion test results show that the Fe28Co20Cr15Mo14C15B6Y2 alloy has the minimum corrosion rate, followed by Fe26Co22Cr15Mo14C15B6Y2, Fe24Co24Cr15Mo14C15B6Y2, Fe30Co18Cr15Mo14C15B6Y2, Fe41Co7Cr15Mo14C15B6Y2 and Ti6Al4V alloys. Specifically, the Fe28Co20Cr15Mo14C15B6Y2 alloy with the highest GFA also has the best corrosion resistance. With the increasing of Co addition, the corrosion resistance of the FeCo-based bulk metallic glasses is first increases and then decreases, which has the same trend of GFA with the change of Co elements. Furthermore, corrosion morphology are different for FeCo-based BMGs with different Co content.

Under the national trend of manufacturing information and integration, cold-rolled sheet plants (CRSP) have begun to transform the manufacturing information in order to meet the fierce market competition. The upper information management (ERP) has already been basically realized in current market. However, the lower automation system and the upper information management system are not well integrated, causing a series of problems, such as basic data delay in the production line, being difficult to keep unanimous with the upper data and so on. To solve the above problems, efforts are paid on the combination of the manufacturing information system requirements and the research of MES system architecture, a set of MES system is established and the whole system architecture and function modules are designed in detail. Through the simulation of this system, it finds that the logistics and information flow can keep unanimous and the production efficiency will be greatly improved, which will create greater economic benefits.

The original idea of antiwindup controller design of equivalent separated-integartor controller structure for phase-lead-lag controller is presented in the paper. The idea is competitive to antiwindup for PID controller which is frequently applied in industry. Thus, mature approach of antiwindup for PID controller can be adopted in solving windup problems in phase-lead-lag controller. From equivalent model and especially from performed simulations, it is seen that the presented solution eliminate the windup.

Particle swarm optimization (PSO) is introduced and tried to optimize the parameters of Street-Phelps model. Here, the inertial adjustment method was used to adopt the inertial weight of PSO. Parameters of Street-Phelps model were optimized by PSO, the performance is compared with other method. Results show that PSO plays an important role in solving global optimization problem, and demonstrate the effectiveness and higher accuracy than other methods.

Many strategies have been adopted to improve thermal degradation of phosphors. Because of the stability and high transmittance of graphene, here we report a novel method of carbon coating on BaMgAl10O17:Eu2+ (BAM) phosphor particles through chemical vapor deposition. The chemical composition, microstructure, and luminescence performance of carbon-coated BAM were characterized carefully. This coating can be controlled within 3-10 atomic layers, depending on the reaction time. Because of the decrease of surface defects and the effective weakening effect of oxidizing Eu2+ to Eu3+ after carbon coating, different layer numbers showed an obvious effect on the optical properties of carbon-coated BAM. Carbon-coated BAM phosphors had higher emission intensity and better oxidation resistance at high temperature than uncoated BAM phosphors. These results indicate that the method of carbon coating on phosphor particles is a promising way to improve the luminescence properties of other phosphors used in lighting and display devices.

Kalman filter is widely applied in data fusion of dynamic systems under the assumption that the system and measurement noises are Gaussian distributed. In literature, the interval Kalman filter was proposed aiming at controlling the influences of the system model uncertainties. The robust Kalman filter has also been proposed to control the effects of outliers. In this paper, a new interval Kalman filter algorithm is proposed by integrating the robust estimation and the interval Kalman filter in which the system noise and the observation noise terms are considered simultaneously. The noise data reduction and the robust estimation methods are both introduced into the proposed interval Kalman filter algorithm. The new algorithm is equal to the standard Kalman filter in terms of computation, but superior for managing with outliers. The advantage of the proposed algorithm is demonstrated experimentally using the integrated navigation of Global Positioning System (GPS) and the Inertial Navigation System (INS).

With the development and the widespread application of computer technology, some of the country's railway professional designing institute and software companies have introduced many culvert design application software. There are many culvert CAD system have been applied in engineering practice, but from the view of practical application and software development, there also have many shortcomings, such as the operation is inconvenient, the function is not perfect, the mapping function does not conform to the designing habits, the function of inheritance and generality is not strong, the management functions of design information and design results is lack and so on.This paper aims at the standardization; normalization characteristics of culvert designing, the parameterization culvert design method were studied, analyzed the data organization structure, the culvert length calculation method, the parametric design and drawing method, then based on them, use the object-oriented programming method, at the VC++6.0 programming platform, developed the railway culvert CAD software systems which based the ObjectARX technology.The software system which has been developed realized the engineering quantity calculation, engineering drawing and engineering quantity form output, improving the efficiency of culvert designing and mapping.

There are three adjustable parameters in the radial basis function, the center of the basis function cj, the width parameter and the output unit weight wj. Through optimization the parameters of the radial basis function by Particle swarm optimization algorithm, a neural network model of underground water is generated, which is used to study the grade of underground water in the ten monitoring points of the black dragon hole. By applying the PSO-RBF model to underground water assessment in the ten monitoring points of the black dragon hole, the results of this evaluation, which correspond with the real conditions, are basically in accord with those obtained by other evaluation methods, and also show the practicability to groundwater quality assessment.

On the basis of research on the steel enterprise information system in the current domestic small and medium-scale iron and discovery of the adequate for the existing system, a idea of the combination the real-time database technology with advanced management services is put forward. By SBO platform we construct the general production framework based real-time database and design its main functional modules; at the same time, we summarize the overview of the interface method with real-time database, finally we realize the program .The program helps raise the level of corporate information production and productivity, reduce production costs significantly and improve their market competitiveness.

Intelligent curtain system can be time switch and achieve more advanced control functions as scene control. The paper introduced curtain applications, electric curtain classification as well as intelligent curtain with new functions. Based on requirements analysis on intelligent curtain of hotel room, functional division of intelligent curtain module was determined. MCU control circuit, data storage circuit and motor drive circuit were designed. The I/O interface of AT89C4051 was used to implement functions of key signal input, voice broadcast or timekeeping. CAN bus was used for communication to complete required curtain linkage function when guest plug card.

Without high quality electronic components, it is difficult for good design electronic component to play roles. In the production process of electronic component, quality control eliminate factors that caused unqualified or unsatisfactory effect by monitoring forming process of quality, so to as achieve requirement of quality. Based on introduction of quality control principle, related factor that affect electronic components screening quality was analyzed and an electronic components quality control method was presented. Specific quality control process and quality control keys were also provided. Quality control example of some electronic components screening shows the feasibility of the proposed quality control method.

A new polycrystalline diamond compacts (PDC) cutter was designed and prepared. The new PDC cutter has fibers that are artificially ordered so as to have the desired geometric angles, and it has a larger number of the cutting edges, enough space for holding chips and interrupted cutting so that it is easier to release heat. According to machining properties of materials and working conditions, on the basis of the theory of thermal equilibrium of moving thermal source, the paper established the mathematical model of temperature field of interrupted cutting used the PDC cutter through reasonable hypothesis. Simulations were performed for the temperature distribution in the tool-work interface and inside the Al2O3 ceramic specimen using finite element method. And experiment of surface temperature of Al2O3 ceramic interrupted cutting used the PDC cutter was carried out. The validation and capability of the finite element model were demonstrated by a satisfying agreement between the finite element simulation results and experimental ones.

In the article, functional requirements need to be analyzed for Chongqing four manufacturing execution systems in cold-rolled steel production line. Combined with the idea of design of the system it can be proposed overall design of information systems and network topologies. Meanwhile, it can also be designed technology and production performance modules based the ERP system platform. Focus on design the production performance of functional modules and interface combined with 1450 actual production process. Production data to be collected need to be establishing the simulation model of the node .Do achieve the simulation of the actual production process. Meantime, the simulation data will be collected to the production performance module through the interface with the real-time database. Chongqing four steel companies as state Enterprises, it should be attached great importance to enterprise information. It has not basically realized the bottom of the production process control system, but also the initial establishment of the upper information management system. However, the underlying automation system and upper management information systems are not integrated. This situation seriously affects the application of effective information systems. The method can only deal with the current manual operations, which leads to the following series of questions: the basis of the data delay line failure; Based data acquisition product line transmission efficiency is low and error rate is high; Production site data scattered in many different processes link manually using the original production data acquisition and transmission are difficult to track products from production through to finished off the assembly line of the whole process; Top manufacturing information system based on production data can not directly access to hard to complete implementation of its functions. In response to these problems, Chongqing four steel companies build MES system, marketing integration, the information management systems and process control systems integration as a whole, and thus the implementation of ERP systems and decision support systems, and further enhance their core competitiveness.[1,7]

This study proposes a novel diamond whisker wheel for grinding of advanced materials. The wheel is designed to have preferable spatial distributions and orientations of diamond whiskers which are prepared using a laser cutting technique. To obtain desirable cutting edge geometries, the whisker edges are formed on a lapping machine with diamond powders. The whisker wheel is used in a machining test on a silicon carbide particulate reinforced aluminum alloy and compared with a tungsten carbide milling cutter. The whisker wheel grinding provides better surface finish and significantly reduced machining force than for milling at the same material removal rate.

The random nature of the abrasive geometries and their distribution in a grinding wheel results in high specific grinding energy and temperature rise, large grinding forces and large deflection in the grinding system. To overcome the shortcomings encountered in grinding, it is necessary to design a new grinding wheel that is structured in controlled abrasive geometries with preferred spatial positioning and orientation. This paper deals with an experimental research of single fibrous-abrasive grinding of a nanostructured WC/12Co Coating. Prepared by the laser cutting of polycrystalline diamond compact (PDC), the single fibrous-abrasive has the dimensions of 0.3×0.6×10mm. The paper reports the research findings on normal and tangential grinding forces in terms of depth of cut and feed rate and discusses the material removal mechanism of nanostructured WC/12Co Coating ground by fibrous abrasive.

Based on the lumped parameter method, this study establishes an experimental scheme for YAG laser absorptance measurement. Laser absorptance is measured on artificial diamond and cubic boron nitride materials under different laser power levels at room temperature. This study presents an analysis of the influence of laser spot size, and number of repeated laser irradiation, heat-insulating material, etc. on absorptance. A theoretical parameter is provided for the process of laser truing and dressing of the corresponding abrasive wheel, and it is important for the analysis and modeling of laser-material interactions. Meanwhile, a reference for measuring the laser absorptance of material with the same physical performance is put forward.

The objective of this study is to experimentally investigate the mechanisms in machining of aluminum/silicon carbide (SiC) composite with two types of diamond whiskers. These whiskers are prepared from polycrystalline diamond compacts (PDC) and chemical vapor deposition (CVD) diamond plates which are cut into dimensions of 10×0.3×0.6 mm with an Nd:YAG (Neodymium-doped Yttrium Aluminum Garnet) laser. In order to obtain sharp and consistent cutting edges, the diamond whiskers are polished with diamond powders of the average grain sizes of 10 µm, 2.5 µm and 1 µm, respectively. A precision grinder is used to conduct machining of the aluminum/SiC composite at a depth of cut smaller than that in the conventional milling but larger than the individual grit depth of cut in grinding. Scanning electron microscopy (SEM) is utilized for observing the machined workpiece surfaces, the whisker cutting edges, and a surface profilometer for inspecting surface roughness and verifying the actual depth of cut in the machined workpiece. The study discusses the mechanisms of workpiece material removal and diamond whisker wear in machining of the aluminum/SiC composite.

This study proposes a design methodology for a novel rotary flexural bearing that is based on the motion principles of elastic flexures. The bearing is capable of providing rotational oscillations of one complete revolution and is characterized by potentially high repeatability, smooth motions, no mechanical wear and no lubrication requirements, no gaps or interfaces, zero maintenance, in addition to its compactness. From the structural characteristics and the basic working principles of the flexural bearings, the study provides a design analysis on the various aspects of the bearing, including material selection, stress analysis and calculations (such as nonlinear finite element analysis, static and fatigue strength designs), motion error analysis and error reduction strategy, parametric design, etc.

A two-dimensional mathematical model is developed to simulate laser truing and dressing of bronze-bonded diamond grinding wheel. Based on the model, the ablation depth produced on bond and diamond abrasives by an acousto-optic Q-switched YAG pulsed laser under different parameters as well as the temperature field on grinding wheel surface produced in the laser ablation process are numerically simulated. An experimental study on laser truing and dressing of grinding wheel is also conducted. In the study, the wheel surface is ablated by the single-pulsed laser and measured with a measurement device for surface topographic information. Both the theoretical analysis and the experimental results indicate that the truing and dressing processes can be simultaneously realized with the laser ablation as a single process.

Nanostructured ceramic coatings has excellent properties, their industrial application depends not only on their fabrication but also on their precision grinding technology, so it is necessary to study the material removal mechanism in grinding of nanostructured ceramic coatings. This paper presents experimental results on how the grinding processes parameters affect the grinding force ratio and specific grinding energy as well as surface roughness in precision surface grinding of nanostructured WC/12Co (n-WC/12Co) coating and also presents SEM observations of surface and subsurface of n-WC/12Co coating ground under different grinding conditions. Furthermore this paper discusses the material removal mechanism in grinding of n-WC/12Co coatings and gives priority to inelastic deformation instead of brittle fracture, which provides theoretical basis for the precision grinding of nanostructured ceramic coating.

Deformation twinning evolution from a single crystal is conducted by molecular dynamics simulations, to elucidate a twinned face-centered-cubic alloy in an experiment with hardness up to 100 times as that of single crystals and with ductility simultaneously. Critical twinning stress of cadmium zinc telluride (CdZnTe or CZT) calculated is 1.38 GPa. All the twin boundaries are along the (11-1) orientation, except the one with the (-111) plane that supports the indentation, interpreting the unidirectional and boundary-free characteristics, confirmed in the experiment. Three twin thicknesses after unloading are 3.2, 3.5 and 16 nm, which is consistent with the experimentally repeated pattern of a lamellar twin with thickness larger than 12.7 nm, followed by one or several twins with thicknesses smaller than 12.7 nm. An inverse triangle of a twin combining with three twins generate a synergistic strengthening effect through the hardening and softening functions, illuminating the ultrahigh hardness demonstrated in the experiment. Twinning takes place in loading and detwinning occurs in unloading, which expounds the high ductility observed in the experiment.

This study focuses on experimental and theoretical investigations of grinding forces for nanostructured WC/12Co coatings. In this study, nanostructured WC/12Co coatings are ground on a precision surface-grinding machine with four diamond wheels of two bond types and three grit sizes. A mathematical model is proposed to predict grinding forces per unit area and per grit, and is used to fit the experimental data. The model is also subsectioned into two different parts with one part fitting grinding forces for the smaller grit depth of cut condition and the other part for the larger grit depth of cut condition. Grinding mechanisms are also discussed in terms of grinding forces and grit depth of cut.

The transverse motion of a saw-wire affects the cutting surface geometry in wire-saw slicing. To evaluate the magnitude of the wire transverse motion under no-slurry and no-workpiece conditions, which should be minimized before starting the slicing process, a high accuracy, noncontact device has been developed. The measuring head of the device is composed of a laser diode module and a dual-element photodiode between which a saw-wire is placed for measurement. This paper elucidates the appropriate positional configurations of the photosensitive surface of the dual-element photodiode and the laser beam focal point with respect to the 160μm diameter wire in the laser beam direction. Furthermore, a measurement experiment is carried out on a wire-saw machine under no-slurry and no-workpiece conditions. The paper reports and discusses the critical issues, such as measurement sensitivity, linearity, and accuracy.

This paper presents a new method, multiple time-varying parameter (MTVP) turning for chatter suppression. Compared to the single time-varying parameter (STVP) turning, the new method uses both time-varying spindle speed and time-varying rake angle to suppress chatter. The paper provides theoretical analyses on the MTVP turning and experimental results to justify the analytical results. It compares the effects of chatter suppression between the MTVP and STVP turnings, and discusses the possible mechanisms of chatter suppression. The paper then concludes that the MTVP turning method is more effective in chatter suppression than the STVP turning method because of the combined effect of the MTVPs. It is demonstrated that the MTVP turning method can suppress chatter by 80%, and can be applied to suppress all kinds of chatter in a machining process.

Although tapping has been widely used for thread fabrication, it is often a time-consuming process causing a delay on an automated production line. This study investigates the fundamental aspects in vibration-assisted tapping. It addresses two major mechanisms that are responsible for torque reduction during vibration-assisted tapping, i.e., friction torque reduction and material property change at an enhanced strain rate. Theoretical analyses are conducted to account for the effect of vibration on tapping torque reduction, and verified by the tapping experiments with and without vibration assistance. Taps of three different sizes and vibrations of two different waveforms are used in the tapping experiments. The theoretical results are applicable to vibration-assisted tapping and other machining processes.

This paper investigates the depth profiles of residual stresses using the sin2ψ method combined with grazing incident X-ray diffraction (GIXD) technique. It specifically focuses on the effects of grinding process on the residual stresses in the thermally sprayed nanostructured WC/12Co and Al2O3/13TiO2 (n-WC/12Co and n-Al2O3/13TiO2) coatings on low carbon steel substrates. The influence of grinding parameters, such as depth of cut (DOC), table feedrate, abrasive grit size and wheel bond type, on residual stresses is studied. The conditions and limitations of X-ray diffractometry for residual stress measurements are discussed. Discussed also is the difference between the average and actual depth profiles of residual stresses. The paper introduces a method for retrieving the actual depth profiles from the measured average depth profiles. Finally, the influence of peak broadening of grain size, anisotropy from different diffraction planes and surface finish of the samples on the measurement results is explored.

This experimental study deals with the effect of machine structural loop stiffness on grinding of ceramics. The objective of the study is to investigate how the loop stiffness affects grinding forces, wheel actual depth of cut (ADOC) and workpiece strength. A compliant workholder is specifically designed and attached to a precision grinder to simulate grinding machines of various compliances so that the effect of machine loop stiffness can be isolated under otherwise identical conditions. Silicon nitride is used as workpiece material and ground with diamond wheels of two bond types and three grit sizes at machine loop stiffness of four different levels. The ground workpieces are assessed in terms of residual workpiece strength, grinding damage, grinding forces, and ADOC. Theoretical analyses are given to indicate that machine loop stiffness can affect on normal grinding forces and workpiece strength. A discussion is provided to reveal how residual workpiece strength is affected by residual stress and grinding-induced damage.

A theoretical model based on mechanics and machine dynamics is presented to describe the effect of machine stiffness on surface integrity of ground silicon nitride. The model accounts for both the static and dynamic structural loop stiffnesses of a precision-grinding machine. Experimental results are also presented to verify the model. A unique workholder with an adjustable compliance is used to achieve a structural loop stiffness in the range of 5–40 N/μm. Silicon nitride is ground with cup-type diamond wheels of vitrified and cast iron fiber bonds. To effectively stabilize the cutting performance of a cast iron fiber bond wheel, the ELID technique is adopted for in-process dressing. The damage depth of ground workpieces is assessed against machine stiffness. The modeling and experimental results demonstrate that there exists a critical machine stiffness in grinding of ceramics. When machine stiffness is higher than the critical stiffness, no chatter should occur in the grinding process. In this case, damage depth increases with the increase of set depth of cut. In contrast, if machine stiffness is lower than the critical stiffness, chatter can occur in the grinding process that may induce grinding damage. The model can also be used to predict the critical machine stiffness for other types of structural ceramics.