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The work considers the application of a magnetic spectrometer (MS) for analyzing the hydrogenation of metals (particularly, titanium and copper). Therefore, for the sake of increasing the sensitivity of the magnetic spectrometer, the following ratios are introduced: (ΔU/U)/(Δd/d) (where ΔU/U is the relative change of the MS signal and Δd/d is the relative change in the thickness of a sample), (ΔU/U)/(Δδ/δ) (where Δδ/δ is the relative change in the depth of eddy current penetration into metal) and (ΔU/U)/(ΔS/S) (where ΔS/S is the relative change in the area of sample). These parameters allow to eliminate or reduce the error in determining the conductivity value. Parameter β that is equal to the product of the sample area and the inverse value of eddy current penetration depth into metal corresponds to the effectiveness of the current penetration into metal. The authors derived a formula that ties the electric conductivity of metal to the number of implanted hydrogen atoms, which allows determining the composition of titanium hydride at different depth of metal.

A nanostructural layer was formed on the surface of 35CrMo steel rods rolled by cross-rolling. The layer microstructure is composed of nano-scale grains and some deformation grains, which contains compressive residual stress of -479Mpa. The surface roughness is decreased from Ra 2.1μm to Ra 0.14μm with improvement of the cylindricity and straightness. The rolling strengthenes the surface but has ignorable influence on the mechanical properties of the rods.

Ni-doped titanate nanorods were synthesized from anatase TiO2 powder and Ni nitrate using a one-step hydrothermal reaction in alkaline solution. The nanorods are straight with lengths a few micrometer and diameters between 80 and 120 nm. The Ni-doped nanorods have the similar structure as hydrogen titanate nanorods of monoclinic structure. Magnetic measurement revealed that Ni-doped titanate nanorods are ferromagnetism at 300K. Electron paramagnetic resonance were studied and the spectra showed that a broad asymmetric signal and a signal in low field appeared due to the Ni ions incorporated into the titanate lattice. The results suggest that Ni-dopants play an important role in the ferromagnetism. The ferromagnetic response could be attributed to Ni intercalated into the titanate lattice.

The research progress of the conventional surface treatment techniques applied in the heat transfer enhancement is reviewed. The research status and development trend of the effects of the low-energy surface prepared by the novel surface treatment techniques such as magnetron sputtering, ion implantation, chemical composite plating and molecular self-assembly on fouling prevention and heat transfer enhancement are also discussed.

The advantages and current problems for the application of high-speed machining technology in mold manufacturing are discussed. The requirements of mold high-speed machining for tool paths are summarized. Using the software of Cimatron E7.0，the NC program of the outer mold for a car engine’s V8 intake manifold is analyzed and optimized designed. Programming technology and optional of cutters have been introduced in detail. In the high speed milling stages, using the new cutters, the hardened mold can be machined to reach the required size, shape and surface roughness, and the machining time is reduced greatly. The method of making high speed NC template based on the software Cimatron E7.0. is introduced. Using this method, the maching efficiency is improved greatly, and the mold’ s surface quality better.

In this paper, a kind of 304 austenitic stainless steel sheets has been investigated, and systemic tests were conducted to study the law and mechanics of work hardening of 304 austenitic stainless steel. The results of microstructure analyzing of 304 austenitic stainless steels showed that when it was deformed by means of tensile testing at room temperature, obvious work hardening was caused by the changes of structure during the deformation. The strain-induced α-martensite, ε-martensite and deformation twins enhanced flow stress obviously, which is the main reason for the strong work hardening in FCC metals and alloys with low stacking fault energy as 304 austenitic stainless steel.

The study introduced tennis rackets and listed their categories firstly. The purpose was to analyze features of tennis racket. This study showed the influence of vibration mode on response of tennis rackets and Player sensitivity to changes in string tension in a tennis racket. Combining bounce of a tennis ball, made out the applications of tennis racket: a analysis of the ball and racket during first and second tennis serves.

The performance of nitrogen and phosphorus removal was investigated in pilot-scale A2/O, A2/O-MBR and mA2/O-MBR processes for treating municipal wastewater. The results show that these processes had a similar COD and ammonia removal efficiency, but A2/O process had better denitrification efficiency than MBR processes. In order to explain the difference of nitrogen and phosphorus removal performance in the investigated processes, specific oxygen uptake rate (SOUR), specific denitrification rate (SDNR), anaerobic release rate and anoxic and aerobic uptake rate of the activated sludge taken from A2/O and mA2/O-MBR processes were compared. The results show that the activated sludge of mA2/O-MBR process had a higher nitrifying activity in aerobic tank than A2/O process, the denitrifying activity in anoxic tanks were roughly equal and A2/O process had a higher denitrifying phosphorus removal activity in anoxic tank than mA2/O-MBR process.

In the past, the instrument in the test station is usually using analogy technology, the testing and inspecting with the device executed with discrete and isolated way, in order to improve the efficiency and effectiveness, the digital instrument of radial direction preciseness for round shape part is designed and composed based on Labview in this research. The mechanic section of this instrument is an inspection device, the acquisition section use the acquisition module of NI, the software of the instrument is developed with Labview. The instrument is fitted to apply in the shop floor of factory.

Cam mechanism has advantages of compact structure, high driving accuracy, good dynamic characteristics, smooth motion, etc. It is implemented that components transmission among the multiple-station of deep groove ball bearing assembly machine by use of cam drive system. Cam followers depending on cam profile achieve the desired law of motion. The core of cam design is the exact cam profile’s design. The quick and easy method of cam profile design through Pro/E software is introduced in follow. Components’ transmission requirements can be met by cam drive system, which is proved through the analysis of motion simulation.

The surfaces of 45 steel and. 1Cr18Ni9Ti are coated with WFCL-11 laser cladding. Microstructure and hardness of their interfaces and surfaces of laser cladding are investigated, and their structure, property, hardness are analyzed under shock load. The effects of the different material ingredients between base and laser clad on their interfaces were found. The little the difference, the better the Interface.

According to the weak rigidity characteristics of thin-walled parts, the material parameters and deformation tools are taken into account. In this paper, the finite element model of high-speed milling process is systematically studied by a large-scale finite element analysis (FEA) software DEFORM-3D with the modified Johnson-Cook model. The simulated results of cutting force, chip morphology, effective stress, effective strain and cutting temperature in deformation zones of thin-wall part are analyzed. On the basis of simulation results, cutting force of high speed milling on thin-wall part is verified. Comparing to the experimental results, the simulated results of cutting force, chip morphology, effective stress and cutting temperature in deformation zones of high speed peripheral milling indicate good consistence and the models established can be used to accurately predict the thin wall deformation. Therefore, numerical simulation method for the thin wall milling deformation control and provide a new way of compensation.

High speed milling hardened mould steel (above HRC50) at pocket corner generates the cutting forces increase and vibration gets fiercely because of the sudden change of cutting direction. It will cause serious wear and possible breakage of cutting tool, and poor quality of parts. Hence, the need to select reasonable cutting parameters and adopt appropriate cutting strategies will help them to achieve their goal. In this paper, the effects cutting parameters including cutting speed, pocket corner angle, feed rate per tooth and radial depth of cut on cutting force and vibration are studied. The results show that sharper pocket corner results in the increase of cutting force and makes vibration strong. Cutting force increase with the increase of cutting speeding, feed per tooth and radial depth of cut. The optimum of cutting speed leads to the decrease of vibration. It is proposed that cutting parameters should be optimized to improve tool life and processing efficiency.

The surfaces of 45 steel and 1Cr18Ni9Ti are coated with WFCL-11 by l pulsating laser cladding. Microstructure and hardness between substrate interfaces and surfaces of laser cladding coating are investigated. And the variation of their microstructure, mechanical properties and hardness of coating surface are analyzed under shock loading. The results show that the different material ingredients between substrate and laser clad effect their interfaces.

While mica papers are used as insulation material binders and reinforcement materials are needed to enhance the mechanical strength which might reduce insulation property of mica paper materials. In this paper aramid fibers and mica flakes are mixed to make composite paper insulation, both have the high strength, heat resistance of aramid fibers and high dielectric strength, corona resistance of mica flakes. When this composite material is preparing, process of mix pulp papermaking was chosen, combined with mica flake and aramid fiber modification. Prepared composite material has properties of high tensile strength, dielectric strength, heat resistance, softness, can be used as high quality insulation.

By defining analysis feature and using analysis results to drive the parametric model, behavioral modeling establishes feature parameter of model automatically for meeting design objectives and making model technology intelligent, that is to say the result could be optimized automatically. In this paper, the application of PRO/E parametric modeling technologies in design of cam profile curve is researched. In order to optimization for dynamic balance of the cam, the methods of defining analysis feature and sensitivity/optimization analysis are proposed by using the technology of PRO/E behavioral modeling. These technologies can enhance the efficiency and quality of the cam design and provide a practical method for 3D modeling of this kind of cam. The fifth generation of CAD model technology named behavioral modeling provides the method of flexible and intelligent solution of practical engineering problems.

On the property of repeated impact load, the attrition, hardening and plasticity warp of the laser cladding sampling were researched by using stress wave spread theory. Results show that under repeated impact loads, stress wave occurs on the metallurgical joint surface of the coat and the basis, forming stretch wave that causes coat slitting and angle splitting. The micro-pits failure and deep exfoliation occur on the coat surface because of the stress centralization. The accumulation of impact load energy cause hardness change and plasticity warp.

The environmental and health hazards associated with chromium-containing solution have aroused wide public concern, so attempts have been made to find alternatives for metal finishing. In the present paper, inhibition effect of acridine on corrosion of hot dipped Zn and Zn-Al alloy coatings on steels in diluted hydrochloric acid was investigated using weight loss test, electrochemical measurement, and quantum chemistry analysis. The results showed that inhibition efficiency increased with inhibitor concentration, and the highest inhibition efficiency was up to 99%. And acridine adsorbed on coating surface by chemisorption. Quantum chemistry calculation results indicated that acridine possesses planar structure with a number of active centers, and showed a good ability of electron exchange with the coating surface.