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The influence of grain refiner on the microstructure and mechanical properties of pure aluminum was investigated by separate and combined addition trace ScZr elements. The results show that the grain refinement effect of 0.2%Zr added alone is better than that of 0.2%Sc, each of them separate addition can make the strength and hardness of alloys increased obviously, and the decrease of the ductility is not remarkable, but the hardness increase of the alloy with 0.2%Sc is more significant than 0.2%Zr because of the strongly solid solution strengthening of Sc. While, the combined addition of 0.2%Sc and 0.2%Zr possesses the most excellent grain refining effect and change the growth morphology from columnar grains to equiaxed ones, the average grain size of the alloy is dropped to only about 100μm, and the strength, plastic and hardness of the alloy meet the reasonable matching, which is largely attributed to the effectively reduce of the Al-Sc eutectic point and the formation of Al3(Sc, Zr) composite particles, These Al3(Sc, Zr) particles can not only keep all the beneficial effect of A13Sc but can act as extremely effective nucleation sites of α (Al) and cause strongly fine-grain strengthening effect.

30CrMnSiA steel is welded by CO2 shielded arc welding with H08Mn2SiA and Ok Aristorod 12.5 welding wire respectively. The effect of welding compositions on the microstructure and mechanical properties of welded joint are studied. The results show that using Ok Aristorod 12.5 for welding, the microstructures of weld metal are mainly composed of acicular ferrite, proeutectoid ferrite and pearlite, the tensile strength of the welded joint is poor. When using H08Mn2SiA for welding, the microstructures of weld metal are mainly composed of fine grain ferrite and acicular ferrite, the acicular ferrite is refined and the content of acicular ferrite is increased, so the tensile strength of the welded joint is improved. Using these two welding wires are welded, the joints both have excellent bending properties.

LY12 aluminum alloy was welded with vacuum electron beam welding, the effect of welding speed and electron beam current on the weld microstructure and mechanical properties of welding joints were studied, the results were shown that with the increasing of welding speed or decreasing of electron beam current, the grains in weld metal were refined, so the joint strength were increased. When the electron beam current was 18mA, the welding speed was 1000mm/min, the grains of weld metal were the finest, and the tensile strength was 373.2MPa. In addition, the micro-hardness of weld metal was much lower than base metal and heat affected zone, and the heat affected zone had certain softening phenomenon. With the increasing of welding speed or decreasing of electron beam current, the micro-hardness of weld metal was increased respectively.

The right panel drawing direction is an important prerequisite for generating qualified parts, an important step before the panel forming simulation is to determine the reasonable direction of the drawing. Manually adjust parts in order to overcome rely on experience, the drawbacks to the drawing direction, the direction of the drawing punch and forming the contact area of the sheet as the goal of automatic determination algorithm. Objective function of the direction of the drawing for the variable contact area in the drawing direction of the feasible region, the use of heritage algorithms to optimize the objective function of the contact area and, ultimately feasible within the contact area corresponding to the drawing direction, that is the best drawing direction. The measured results show that the direction of the drawing based on genetic algorithm, the automatic algorithm can fast and accurate to obtain the optimal direction of drawing.

The effects and the mechanisms of namo TiN on the high chromium cast iron are studied, the material has been prepared through infiltration casting and addition of high carbon ferrochrome powder and nano TiN powder. The alloy is formed on the surfaced of guide plate, and the wear resistance of alloy have been studied by means of SEM, XRD micro-analysis and wear-resistant performance. The grain size and the type of carbide in the organization are affected by nano TiN, and the wear resistance of carbon chromium alloy layer is affected by the type of carbide; when the addition of nano TiN is 1% (wt), the grain size is apparently refined, overeutectic primary M7C3 in the hypereutectic is precipitated uniformly in considerable amounts, therefore the wear resistance of alloy can be improved effectively.

The mineral composition of the solidified blast furnace slag and the occurrence of special components CaF2, K2O, Na2O, RexOy and ThO2 were researched by optical microscope analysis, X-ray diffraction analysis and scanning electron microscopy and energy spectrum analysis. The results showed that the major minerals in solidified furnace slag are akermanite and gehlenite; the special component CaF2 is not hosted in the cuspidine (3CaO•2SiO2•CaF2), but in the magnesium and aluminum silicate mineral; the special components K2O，Na2O is hosted in akermanite, magnesium and aluminum silicate mineral and perovskite; the element thorium cannot form an independent mineral, but coexist with the rare earth element Ce in the perovskite. The results will lay a foundation for further study on the influence of these special components on the crystallization behavior of glass-ceramics.

Streets constitute the skeleton of the commercial space in traditional towns, and the commercial buildings are its flesh and blood. The under-eave space serves as the transition of the streets and commercial buildings, and it is viewed as a part of both streets and commercial buildings. However, the variable conformation and contents of the under- eave space lead to temporal polymorphism and spatial multi-functionality, which manifest its commercial value ,and become an important component of traditional commercial districts.

In this study, Nd: CW CO2laser were used in LSA experiment on Steel C1045 with four different systems alloyed by Sub-Micron Ceramics, namely Ti+C, TiO2+C, TiC, Ti+V+C. The high hardness alloyed coating was prepared on the surface of Steel C1045 adopting laser alloying process for the ideal reinforced effect of surface that we expect. The microstructures of the four different alloy systems were analyzed by SEM. The microhardness and the friction coefficient of these laser alloying layers were examined, then the abrasion resistance and the main wear mechanism were summarized. According to the experimental results, comprehensive properties of Ti+V+C system were the most excellent in all systems.

Mn18Cr2 steel is one of austenitic deformation strengthening steel. The existing form of TiN and its influence on the austenitic structure in the steel by adding small amounts of TiN nanoparticles are discussed in this study, which may provide some advices to explore new way to strengthen high manganese steel. The microstructures of Mn18Cr2 steel added small amounts of TiN nanoparticles are observed by Transmission Electron Microscopy (TEM). The results show that TiN nanoparticles exist in austenite and there have a very good match interface between the two phases, the crystal face relationship are {220}γ//{220}N, {422}γ//{422}N, (111)γ //(200)N , orientation relationship are γ// N, γ//N, [112]γ // [011]N, moreover, the relationship of (111)γ and (200)N is not only parallel but also coherent. Meanwhile, there are many high density dislocations, a small amount of stacking faults, twins and ε-martensite in the austenite due to the role of TiN nanoparticles.

According to the capability require of the automotive transmission control mechanism（ATCM）, and entered into test method by the automotive accessory corporation and user，developed the performance test bench of ATCM，and introduce the makeup and function of test bench and control system. The test results showed that this test bench has many merits such as high test precision，stable anti-interfere capability，rapid fix test element，perfect function of man - computer dialogue，and see about history data facilely. It can provide reliable test method for the ATCM’s test and scientific reference for improve on ATCM.

This paper has proved that the HIC of local engine hood collision area is relative to the distance between the collision point and potential secondary collision point, and with the rigidity of the second collision point, in the process of protection for pedestrians. The pertinence formula was built and the high risky spot of each local collision areas was doped out quickly, and the accuracy of the formula is validated by the subsequent real car collision test.

Activated carbons were prepared from waste particle board (WPB) by K2CO3 activation. The effects of different parameters, such as chemical/WPB ratio, activation time and activation temperature on yield, the methylene blue adsorption, Iodine number of activated carbon were investigated. The optimum conditions were determined by the method of factor analysis and the orthogonal design as follows: activation temperature 900°C, K2CO3 (50% concentration)/ WPB 4.0, activation time 60 min. Amount of methylene blue adsorption, Iodine number, phenol adsorption, BET surface area and the yield of activated carbon prepared under optimum conditions were 82.5mg/g, 1234mg/g, 185mg/g, 1026m2/g and 30.4%, respectively.

In this study, calcium nitrate(Ca(NO3)2•4H2O) and phosphorus pentoxide(P2O5) were used as precursor to prepare hydroxyapatite(HA) layer by sol-gel method, followed by a dipping-coating method to coat HA layer onto Ti. Phase formation and microstructure were investigated by XRD and SEM to study the influence of atmosphere on the property of HA layer. The results revealed that there exists no large cracks in the layer which was heated in the nitrogen, leading to a good surface quality compared with the layer which was heated in the air. And there is no obvious difference in crystallinity and volume fraction of HA in the layer when adopting heat treatment in different atmospheres.