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Casting Mg-Li alloy samples were subjected to annealing and aging treatment respectively, and the corrosion resistance of different samples was investigated by immersion test and electrochemical impedance spectroscopy measurement in 3.5% NaCl solution. The results show that the corrosion resistance of the as-cast sample is the best,the aged sample is the second, and the annealed sample is the worst to resist corrosion.

Effects of niobium element adding method and addition content on the microstructure, thermal conductivity and melting point of Cu-Ni-Nb alloys prepared by vacuum non-consumable arc-melting were studied. We found that it is difficult to dissolve high melting point element Nb into Cu-Ni alloy by one-step smelting. However, Nb can be dissolved into Cu-Ni alloy in style of Nb-Ni master alloy by two-steps smelting. New phases Ni3Nb and Ni8Nb generate in matrix of Cu-Ni alloy. In addition, the thermal conductivity coefficient of Cu-Ni-Nb alloy increases as increasing the content of Nb, while melting point of that alloy decreases as increasing the content of Nb. Moreover, the thermal conductivity coefficient of Cu-20Ni-3Nb alloy is 43.23W/m•k, while melting point of that alloy is 1146°C. That meets the requirement of pure copper casting process.

In this paper, pearlitic steel wire with/without reserved texture were investigated with the help of mechanical test system, scanning electron microscope (SEM) and XRD. Experimental result shows that: Tensile strength of two wire are almost same. After cold drawn tensile strength of wire with reserved texture are higher than tensile strength of the without one. Before cold drawn, two wires have same microstructure of isometric pearlite and after drawing the wire with reserved texture has less shear deformed pearlitic colony. Intensity of fiber texture in the wire with reserved texture are stronger than the without one at all strains. The stronger texture mean the orientation of α-ferrite lamella were more closely and improve working hardening rate of pearlitic wire.

Aiming at the abnormal landing of the aircraft which caused by the invalidation of the undercarriage, a safe auxiliary system for aircraft’s forced landing is proposed. Firstly, the article introduces the basic compositions and the main functions of each part in the system, and proposes the undercarriage robot based on the aircraft arresting system and also the underground rail system based on the steam-driven catapult principle is put forward. Secondly, the detail introductions on the system’s operating principles for aiding the forced landing of aircraft are given separately from starting, docking, decelerating and separation. At last, an expert control system based on knowledge base is proposed for realizing the calculation of docking position, velocity matching and the optimal decelerating scheme.

Al-0.6%Cu alloy processed by equal channel angular pressing (ECAP) was investigated in this study. The samples processed with 1, 2 and 4 ECAP passes were annealed at different temperatures. And the microstructures of the Al-0.63%Cu alloy samples were observed. The results show that the grains of the alloy are refined to sub-micron level after multipass ECAP. Moreover, it is found that the recrystallization temperature of the Al-0.6%Cu alloy samples decreases with increasing the number of ECAP passes. Based on the study above, effect of cold rolling reduction and ECAP passes on recrystallization temperature of materials should be further investigated.

Based on POC set theory and SOC unit, a 1T3R parallel stable platform is proposed. The Single cylinder force analysis is studied. Then uses Newton-Euler method, gives full consideration to these various factors: without neglecting the ball screw rotation, friction between the spherical joint, the mass and the moment of inertia of electric cylinders, based above the dynamic theoretical Analysis of the stable platform is researched. The paper makes the guide sense for the follow-up research and the application of the 1T3R mechanism.

A new model based on least square support vector machines (LSSVM) and capable of forecasting mechanical and electrical properties of Cu-15Ni-8Sn alloys has been proposed. Data mining and artificial intelligence techniques of copper alloys are used to examine the forecasting capability of the model. In order to improve predictive accuracy and generalization ability of LSSVM model, leave-one-out-cross-validation (LOOCV) technique is adopted to determine the optimal hyper-parameters of LSSVM automatically. The forecasting performance of the LSSVM model and the artificial neural network (ANN) has been compared with the experimental values. The result shows that the LSSVM model provides slightly better capability of generalized prediction compared to ANN. The present calculated results are consistent with the experimental values, which suggest that the proposed LSSVM model is feasible and efficient and is therefore considerd to be a promising alternative method to forecast the variation of the hardness and electrical conductivity with aging temperature and aging time.

Al-3.9wt.%Cu alloy was subjected to equal channel angular pressing (ECAP) and subsequent low temperature annealing treatment, and the corrosion resistance of the samples was investigated by potentiodynamic polarization measurements in 3.5% NaCl solution. The results show that the corrosion rate of the ultrafine-grained alloy increases, in comparison with the coarse-grained alloy. Meanwhile, it is noted that the corrosion resistance of the alloy subjected to ECAP can be improved by relief annealing.

The grain oriented silicon steel containing 3%Si-0.5%Cu was produced by low slab reheating temperature technique. The precipitates were observed during the mainly process such as hot rolling, normalization, primary and secondary recrystallization annealing. The species, size, density and shape of precipitates were identified using TEM technique. The results indicate that Cu2S and AlN are mainly inhibitors which precipitate during hot rolling and normalization respectively. After primary recrystallization annealing the precipitation size of Cu2S is in the range of 30~40nm while the mean size of AlN is ~50nm, which could inhibit grain growth. In addition, the precipitation of MnS is inhibited comparing with the precipitation of Cu2S.

To investigate nutrient removal and biological community structure in wastewater treatment system under different ratio of C/N/P, hybrid biofilm reactor (HBR) and sequencing batch reactor (SBR) in lab scale were set up. Results showed that both HBR and SBR achieved the best removal efficiency of nitrogen and phosphorus when C/N/P=100/6.25/1. With the rise of C/N/P from 50/6.25/1 to 100/6.25/1, the removal efficiencies of NH3-N were greater than 93% in three phases of both reactors; the efficiencies of TN were increased from 65% to 79% in SBR while these values at HBR were from 73% to 86%; the efficiencies of TP were increased from 42% to 93% in SBR while these values at HBR were from 32% to 93%. Microbial community structure response to different C/N/P was determined by PCR-DGGE technology. Similarity coefficient was lowest and denitrifying phosphate accumulating bacteria became dominant bacteria in SBR when C/N/P was 100/6.25/1. There were many functional bacteria in HBR, such as bacteria for removing nutrients (Uncultured BacteroidetesFJ828150), bacteria for removing organic (Uncultured Saprospiraceae) bacteria for removing nitrogen (Ferribacterium sp.), and nitrifying bacteria (Uncultured Nitrospira sp.) which became dominant bacteria. Because of microbial diversity index of biofilm was up to 3.3, similarity coefficient was as low as 43.4%.

Cu-32wt.%Zn alloy was subjected to equal channel angular pressing (ECAP) and subsequent low temperature annealing treatment, and the corrosion resistance of the samples was investigated by potentiodynamic polarization measurements in 3.5% NaCl solution. The results show that the corrosion rate of the ultrafine-grained alloy decreases, in comparison with the coarse-grained alloy. Meanwhile, it is noted that the corrosion resistance of the sample subjected to ECAP can be further improved by relief annealing.

Titanium dioxide has been used for environmental applications. However, pure TiO2 has low photocatalytic efficiency outdoors because of its large energy band gap. Higher nitrogen-doping level would have lower band-gap energy and it would make it possible to improve the utilization ratio of solar energy. Heavily nitrogen-doped TiO2 could be obtained by using ion beam assisted deposition (IBAD) technique. Acceleration voltage is a very important parameter of IBAD technique and will affect the processes of depositing thin film. Under the given experiment condition, acceleration voltage had little effect on the structure and absorbance spectra of the obtained nitrogen-doped titanium oxide thin films, but had great effect on the deposition rate, composition and surface morphology of the thin films. When the accelerate voltage was 250V, the deposition rate was the highest (about 9.0 nm/min), the resulting TiO2-xNx films contained nitrogen levels up to x =0.45, the structures were mostly crystalline anatase and the amount of shift was observed about 500 nm. The optimum acceleration voltage is about 250V under the given condition.

A new method to correct a distorted image is proposed in this paper, which is based on the relationship between image magnification and distortion coefficient. First, the image magnification is solved. Then, the image distorted coefficient can be obtained with simple linear operation. Ultimately, experiments are carried out, and the correction results obtained by the collinear points-based method are compared with the method proposed in this paper. The results show that both provide good correction effects. At the same time, the accuracy of the new proposed method is higher. The proposed method takes the advantages of simple algorithm, few known conditions and fast computing speed. The new method has great significance in engineering metrology and complex condition.

The kinetics of phase transformation in Cu-15Ni-8Sn-XSi alloys alloy was studied through the measurement of the relationship between electric conductivity and volume friction of the new phase. The phase transformation kinetics equation was deduced from the Avrami empirical formula based on the linear relationship between the electrical conductivity and the volume fraction of the phase transformation. The electrical conductivity calculated by the physical model was also obtained. As comparisons, a new model based on least square support vector machines (LSSVM) and capable of forecasting electrical property of Cu-15Ni-8Sn-XSi alloys has been proposed and tested on the same data. The present calculated results of both the physical and artificial intelligence models are in very good agreement with the experimental values. Two models are feasible and efficient to forecast the electrical conductivity of Cu-15Ni-8Sn-XSi alloys.

The present studies are to investigate the microstructure features and macroscopical hardness during transformation from austenite to pearlite without and with 12T magnetic field on Fe-1.1%C alloy. It is found that 12T magnetic field can increase the area fraction of abnormal microstructure and the average width of secondary cementite in Fe-1.1%C alloy by remarkably decreasing the Gibbs energy needed for the ferrite transformation. The macroscopical hardness of the specimens heated with 12Tmagnetic field is lower than the specimens without magnetic field. The reason is that the magnetric field increase the lamellar spacing of pearlite

The proton/lithium exchange property of the garnet-related lithium-ion conductors Li5La3Ta2O12 is shown to occur at room temperature under ambient air. The internal friction, TGA analysis, and IR spectroscopy techniques are used to investigate the reaction mechanism. XRPD analysis demonstrates the topotactic character of the exchange reaction. The water gas in ambient air is adsorbed on the grain surface and then to exchange proton for lithium ion into the garnet structure,(Li5-xHx)La3Ta2O12. The H+/Li+ exchanging processes are reversible. When the measured temperature is higher over 573K, the internal friction peak gradually shifts toward lower temperature and the like garnet-like phase is recovered.

In this paper the hydroxyapatite fibers reinforced chitosan nanocomposites with high hydroxyapatite dosage (70~90 wt%) were synthesized by in-situ hybridization. The semi-permeable membrane was used to control the process of hybridization and morphology of hydroxyapatite. The compositional and morphological properties of nanocomposites were investigated by FTIR spectroscopy, X-ray diffraction, and transmission electron microscopy. The results showed that the hydroxyapatite were carbonated nanometer crystalline fibers with high aspect ratio (about 25) and dispersed uniformly in the nanocomposites. The high-resolution image indicated that the growth of nano-hydroxyapatite crystallites in the chitosan matrix preferred in the c-axis. The mechanical properties of these nanocomposites were enhanced dramatically and the compressive strength increases almost to 170MPa when the hydroxyapatite content is 70 wt%. The in vitro tests indicated that the composites have high bioactivity and degradation. These properties illustrated the potential application of this kind of nanocomposites for bone tissue engineering.

Shilu iron mine is an important iron mine in China, with deposits of 314 million tons and average ore grade of 51.15%, and is the biggest iron-rich deposit in Asia. Beiyi iron open-pit is the biggest open-pit of Shilu iron mine. The height of west wall of Beiyi open-pit is 400m, and the height will be 492m in 2013. Due to the effects of tectonic movements, the rock mass is fractured seriously, and more discontinuities paralleling the slope are unfavorable to slope stability. Since 1998, the deformation of slope is obvious, with horizontal displacement of about 2.9m and vertical displacement of about 1.5m. On the basis of in situ investigation and monitoring data, deformation mechanism of west wall of Beiyi open-pit is analyzed in detail. The results of this research are useful to the slope safety assessment and the following treatment design.

The diffusion processes of lithium ions in La2/3-xLi3xTiO3 (x=0.06, 0.11) compounds were investigated by dielectric relaxation method. Prominent relaxation dielectric loss peaks, peaks P1 and P2 in La0.56Li0.33TiO3 and peaks P3 and P4 in La0.61Li0.18 TiO3, were observed. From the shift of peak position with frequency, the activation energy of 0.36~0.42 eV and the pre-exponential factor of relaxation time in the order of 10-14 ~ 10-13 s were obtained if one assumes Debye relaxation processes. The activation energies of lithium ion diffusion in La2/3-xLi3xTiO3 compounds and the characteristic vibration frequency for the ionic hopping motion are higher than those measured by 7Li nuclear magnetic resonance (NMR) spectroscopy and that of the typical phonon frequency (about 1013Hz). These values of relaxation parameters strongly suggest the existence of interaction between the relaxation species (here lithium ions or vacancies). Basing on the coupling model, the decoupled relaxation parameters of the dielectric relaxation peaks is: P1 (0.14 eV, 2×10-13 s), P2 (0.25 eV, 1.8×10-13 s), P3 (0.17 eV, 4×10-13 s) and P4 (0.3 eV, 2.7×10-13 s). These decoupled parameters are very close to the NMR measurement results and the reciprocal of the typical phonon frequency. Judging from the relaxation parameter of the peaks and combining with the crystallographic characterization, it is suggested that the P1 (P3) and P2 (P4) peaks are associated with the lithium ion diffusion in the ab planes and between the adjacent ab planes, respectively.

LaF3 powder is prepared by means of three methods . The traditional precipitation of LaC13 with HF action, sol-gel of La (CH3COO) 3 with NH4F action then gel is handled by infrared furnace and microwave method of La (CO3)3 as La source with NH4F action to become LaF3 Ultra-fine powder under the action of microwave. Through the SEM photographs, it can be revealed that the powder particles are different. Precipitation particles diameter is 10 μm; sol-gel method of particle is 1 um and there are a lot of needle-like particles; microwave particles is 100nm.

Choose wheat straw, corn straw and thatch as the shock isolation layer materials, the static state function and the dynamic state mechanics function experiment have been made to them. This article also analysis the influence of anti-vibration ability by elastic modulus and water saturation rate under the same layer thickness.

Marine propeller is a kind of typical part with free-form surface. The surface shape of propeller blade is very complex, and it is difficult to be described by general mathematical expressions, so that the modeling of propeller is very cumbersome and error-prone. To solve this problem, firstly, three-dimensional point data of propeller blade is calculated by VC/MFC programming technology and access technology of database based on projection principle of propeller blade. And then, automation and parameterization of solid modeling for propeller of different map forms are realized by programming with the interactive programming language of UG/Open Grip based on UG software. The parametric modeling system provides accurate three-dimensional model for automatic programming, dynamic simulation and numerical analysis of propeller, and improves the design efficiency of systematic propeller, and has very good practical value.

A novel calix[4]arene chromophore 1 was synthesized by introduction of two D-π-A units (4-nitrophenyl)azophenyloxy groups) on the lower rim of calix[4]arene. The measurement results of hyper-Rayleigh scattering (HRS) and UV-vis spectra show that the static first molecular hyperpolarizability of the chromophore 1 is more than two times that of the corresponding mono-D-π-A unit reference compound 4-(4-nitrophenylazo)phenol 2, without causing red-shift of absorption band.

Study the affection of work performance and mechanical properties with different contents of fly in the self-compacting concrete. The mixture content of fly ash is respectively 16%, 20%, 30% and 40%. Carry on the experiment of slump, rate of spread, cube compressive strength, cube split tensile strength, prism axial compressive strength as well as the elasticity modulus of self-compacting concrete. Simultaneously obtain the corresponding stress-strain curve, and make the data fitting to it. The experiment and the analysis result show that there is a reasonable rang of mixture content of fly ash. When mixture proportion was suitable, the work performance of self-compacting concrete can be effectively improved, but the strength is also influenced. The early strength reduces much. This experiment provides the theoretical basis for reasonable application of fly ash in practical projects.

The optical fiber corrosion sensor was applied to measure the steel corrosion based on Fe-C corrosion-sensitive metal film, the sensing principle of which was introduced. Because corrosion was a complex random phenomenon and the corrosion surface of Fe-C alloy film of the optical fiber corrosion sensor possessed fractal characteristics, the image fractal dimensions was as a quantitative index of the sensor corrosion degree. The experimental results showed that the complexity level of the sensor surface morphology increased and the optical output power increased along with the increase of fractal dimensions. Therefore, a new method was provided for the research of the optical fiber corrosion sensor.

In this paper, the influence of correlation of variables on structural reliability is discussed. Using importance, condition and duality sampling techniques of Monte Carlo method, accepted accuracy can be obtained. For the limit state function, the correlation of random variables will influence structural reliability, and the influence can be described. For the case of positive correlation, reliability will increase as the the correlation coefficient raise. For the case of negative correlation, reliability will drop as the correlation coefficient raise. The level of influence depends on the slope of limit state equation in standardized coordinate. When k=1, the influence attains maximum intensity for both cases.

The unfired bricks which regarded as a new green wall material are produced by fly ash, shell ash (renewable resources), cement and lime as the main raw materials, and together with the chemical activator. The essential mixture ratio is designed on the experimental result of its mechanical properties and durability. The bricks are water conserved in the condition of normal temperature and pressure. We respectively research the compressive and flexural strength and frost resistance of the unburned brick. The results show that the optimum mixture ratio for unburned bricks are: fly ash 41%, cement 25%, lime 15%, shell ash 15%, gypsum 4%, SBR 3%, fiber 0.10%, water-reducing admixture 0.5%, sand cement ratio 0.5 and water cement ratio 0.3. We obtain the properties of unburned bricks that produced by vibration with the optimum mixture ratio. The minimum compressive strength of one brick more than 30MPa, the mass loss of one brick after 15 times freezing and thawing cycles is only 1%, and the compressive strength after frost reaches 26MPa, the overall performance of bricks can satisfy the requirement of " China Fly Ash Brick " standard.

Based on eight groups of uplift tests for screw anchors with different embedded depths and different plate sizes, a method is given to compute the bearing capacity of screw anchor within critical depth in coarse sand according to analysis on force transmission route and failure characteristics. Within critical depth, bearing capacity of screw anchor is proportionate to embedded depth and the area of screw plate, and the failure surface is inverse triangle in shape. Beyond critical depth, the bearing capacity of screw anchor won’t increase with depth, and the failure surface is funnel in shape. Critical depth is about 10 times the diameter of screw plate. In both cases, the include angle between failure surface and the vertical plane equals to 0.5 time the friction angle of the soil.

The present work has investigated the influence of calcium on the microstructure and properties of AISI M2 high speed steels. The results show that the as-cast structure consists of the iron matrix and networks of M2C eutectic carbides, which are greatly refined in the ingot modified by calcium. Meanwhile, the morphology of M2C evolves from the plate-like shape into the fibrous one. Compared with the plate-like M2C, the fibrous M2C is less stable at high temperatures, which promotes the spheroidization and refinement of carbides. Therefore, M2 steels modified by calcium obtain higher hardness and red-hardness after heat treatment than those without the addition of calcium.

The present work has investigated the effect of aluminum on the solidification microstructure of M2 high speed steel. The results show that the as-cast structure is refined and the networks of M2C eutectic carbides are distributed more homogeneously with the addition of aluminum. Meanwhile, the morphology of M2C changes from the fibrous shape to the plate-like one. Despite of the same crystal structure, the microstructure differs greatly between the two carbides. Compared with the fibrous M2C, micro-twining is formed in the plate-like M2C, resulting in the orientation changes between different plates. It is expected that the solid/liquid interface structure of M2C may evolve from the non-faceted into the faceted due to the addition of aluminum.

In order to research the problem of rescue chamber colliding with the tunnel wall. The theoretical model of rescue chamber has been formed, based on the principle of energy conservation, by using theories of plates and shells, large deformed plate and shell, and by analysis of dynamic response of mine rescue chamber under axial impact load. This model includes initial velocity, contact force deformation energy and shell deformation. Dytran software was applied to build the finite element model of the rescue chamber contacting the rigid plate. Through comparison emulation result and theoretical analysis result, this model is proved to be highly reliable. The theoretical calculation and the simulation indicated that there were obvious relationships among the ability of the mine rescue chamber under axial impact load with the thickness, depth of flat spherical shells. If the thickness or depth increases, then the chamber could stand more. It is also confirmed that increasing the depth of flat spherical shells can minish the impact force for making impact process abate, which provides a basis for the research of rescue chamber.

In order to improve the heat-insulating capability of the refuge chamber’s shell and reduce energy consumption of the cooling system, the horizontal cylindrical mobile refuge chamber for coal mine was taken as the research object. By selecting two connection types between the inner shell and the outer shell for calculation, which were direct connection type and indirect connection type, and comparing these with the connectionless heat transfer, the heat transfer process in the refuge chamber subjected to thermal loadings of constant temperature was respectively discussed with numerical analysis method. Effect of heat bridges to heat transfer of the refuge chamber’s shell was analyzed. The analysis results showed that the average heat flux through direct connection heat bridge and indirect connection heat bridge had respectively increased by 668% and 30% than that of the connectionless heat transfer. The influencing scope of the former was larger than the latter’s. And more heat entered the refuge chamber through the direct connection heat bridge. Therefore, the indirect connection type should be used in the design of the refuge chamber’s shell.

The scratchiness of ramie fabric, to some extent, restricts the development of ramie products, although it has been improved of the underwear ramie fabric to a certain degree, however, it is at the cost of sacrificing the unique style of ramie fabric. How to keep the special style of ramie fabric and eliminate scratchiness in the meantime is yet to be solved. This study analyzed the causes for scratchiness, discussed how to choose the fabric’s geometry, density and tightness, and established a theoretical formula for the geometric structure of non-tight structure ramie fabric, as well as warp and weft density and tightness, further more, the study proposed a structural phase range and maximum weave tightness to overcome the ramie fabric’s scratchiness. All of these offered the theoretical basis for ramie fabric design.

Continuous casting has been widely applied in the production of steels and other metals. However, it has been rarely used in producing high speed steels, which are still manufactured by the conventional method of mould-casting. Thus, little is known about the microstructure of high speed steels made by the continuous casting technology. In the present work, AISI M2 steel is produced by horizontal continuous casting and the difference of solidification microstructure of ingots by different casting technologies has been examined. The results show that the networks of M2C eutectic carbides are greatly refined in the ingot by continuous casting compared to that by mould casting. Meanwhile, the morphology of M2C eutectic carbides changes from the plate-like type to the fibrous one, due to the increasing cooling rates. Compared with the plate-like M2C, the fibrous M2C in continuous casting ingots is less stable and decomposes faster at high temperatures, spheroidizing obviously after heating and refining dimensions of carbides.

Based on the broadly obtained experimental results, a particular simulant curve was firstly given to visually describe the variety of friction coefficient (μ) with the thickness of sulfide layer on hard steel substrate. The curve includes two inflexions named super-critical thickness (tC2) and sub-critical thickness (tC1) respectively. By means of “micro-peak and soft/hard plane” contact model given in the present work, physical definition and influence factors of tC1and tC2 were discussed in detailed. Theory analysis presents that a friction-reducing coating would obtain a minimum of μ at tC1，and good friction-reducing and anti-wear behaviors with its thickness range from tC1to tC2. Therefore, it is beneficial to improve tC2 or decrease tC1, especially keep a wide difference ( tC = tC2 - tC1). Herein, two optimized designation principles of the sulfide layer on a hard steel substrate were presented, which apparently apply to all lubricate situation with soft layers.

CrNx films were synthesized under graded/constant bias by DC magnetron sputtering. In the present work, the graded bias deposited CrNx films have both (111) and (200) orientations while only (111) orientation in low bias (-20 V) and (200) orientation in high bias (-200 V). Both the magnitude of bias and preferred orientation result in the variation in their surface morphology from pyramidal (loosen) to cellular (dense) structure. The hardness of the graded films is between the low and high constant bias ones. The relationship between the hardness and bias gradient is similar with the relationship of hardness and the content of (200) preferred crystallites, which implies the fine (200) preferred crystallites is an important factor for hardness of graded bias films.

By applying nonequilibrium Green’s function formalism combined first-principles density functional theory, we investigate the electronic transport properties of 3,3′,5,5′-Tetra-tert-butyl-azobenzene(meta-TBA) optical molecular switch. This molecular switch comprises a meta-TBA molecule with the trans and cis forms, which can be reversed from one structure to another one upon photoexcitation. The influence of HOMO-LUMO gaps and the spatial distributions of molecular orbitals on the electronic transport through the molecular device are discussed in detail. Theoretical results show that there is a large current ratio in bias window, which suggests that this system can be one of good candidates for optical switches due to this unique advantage, and have real applications in the molecular circuit.

The erosion wear behavior of TiN coatings with growth defects was studied. The TiN coatings were produced on a hard metal by ion beam enhanced pulsed filtered vacuum cathode arc deposition. The erosion wear was tested with a gas blast apparatus. In the test, TiN coatings were impacted at an impingement angle of 90° by angular SiC solid particles with an average diameter of 124um. The maximum depth of the erosion scar measured by the optical profiler was used to evaluate the erosion wear loss of the coatings. The coatings proved to have much lower erosion rate than that of the substrate material and consequently, the erosion rate increased significantly to the high level of the hard metal substrate after the coatings were penetrated. The failure mechanism was revealed by examining the surface morphologies of the coatings before and after the erosion test. The erosive wear of the TiN coatings with growth defects behaved as typical brittle materials. The damage mechanism of the coatings with growth defects was described.

A reasonable process route is important for assuring the product quality and improving the production efficiency. This paper analyzes the sequencing essence of box part working step，and on the basis of deducting the concept of “Inner Product Angle Cosine of n Dimension Vector”, this paper advances a new algorithm called as “Inner Product Angle Cosine of n Dimension Vector” to sequence the working procedure. Through analyzing the algorithm flow and combining with the example used to demonstrate it, this algorithm is proved to own a more reasonable math theory basis, an overall optimization character and a stable convergence character in a more strict sense.

Tool selection is the important content of CAPP, and a great many influence factors and selection principles must be considered during tool selection. For the unreasonable phenomenon during tool selection and usage in present manufacturing enterprise, first the rule reasoning and fuzzy theory method are used to select proper tool set according to the processing conditions, then grey correlation analysis method is used to calculate the weight value of each tool and compare superiority of the these tools, and the best tool in existing conditions is obtained. Grey theory is used in tool selection to work out the problem of insufficient and incomplete information in the process of tool selection, and the cumbersome factors are simplified, the accuracy and efficiency of tools selection are improved. The research result has all-right reference meaning to other decision-making systems.

During manufacturing Cu-30Ni alloy condenser tube, the defects such as crack were fatal to the successive processing operations. The cause of failure induced by manufacturing defect in Cu-30Ni alloy tube was investigated by employing nondestructive penetrative test technology, optical microscope, scanning electronic microscope with energy-dispersive spectrometer and tensile properties test. It was found that cracks including long continuous crack, short discontinuous crack and chevron crack were the main problem caused the manufacturing failure at the industrial production line. There were three principal evolutions of cracks, i.e., inter-granular, trans-granular and the combination of them. These cracks could decrease the elongation by about 10% in comparison with that of good tube, whereas it had no effect on yield ratio. From fractography around the crack, it was seen that there appeared to be different inclusions with different compositions. These inclusions were responsible for the manufacturing failure during the processing of the Cu-30Ni alloy tube.