MoS2/Zr composite films were deposited on the cemented carbide YT14 （WC＋14%TiC＋6%Co） by medium-frequency magnetron sputtered and coupled with multi-arc ion plated techniques.The influence of negative bias voltage ...MoS2/Zr composite films were deposited on the cemented carbide YT14 （WC＋14%TiC＋6%Co） by medium-frequency magnetron sputtered and coupled with multi-arc ion plated techniques.The influence of negative bias voltage on the composite film properties,including adhesion strength,micro-hardness,thickness and tribological properties were investigated.The results showed that proper negative bias voltage could significantly improve the mechanical and tribological properties of composite films.The effects of negative bias voltage on film properties were also put forward.The optimal negative bias voltage was -200 V under this experiment conditions.The obtained composite films were dense,the adhesion strength was about 60 N,the thickness was about 2.4 μm,and the micro-hardness was about 9.0 GPa.The friction coefficient and wear rate was 0.12 and 2.1×10-7 cm3/N·m respectively after 60 m sliding operation against hardened steel under a load of 20 N and a sliding speed of 200 rev·min-1.展开更多
An interpolating reproducing kernel particle method for two-dimensional （2D） scatter points is introduced. It elim- inates the dependency of gridding in numerical calculations. The interpolating shape function in th...An interpolating reproducing kernel particle method for two-dimensional （2D） scatter points is introduced. It elim- inates the dependency of gridding in numerical calculations. The interpolating shape function in the interpolating repro- ducing kernel particle method satisfies the property of the Kronecker delta function. This method offers a mathematics basis for recognition technology and simulation analysis, which can be expressed as simultaneous differential equations in science or project problems. Mathematical examples are given to show the validity of the interpolating reproducing kernel particle method.展开更多
To assess the meshing quality of spiral bevel gears,the static meshing characteristics are usually checked under different contact paths to simulate the deviation in the footprint from the design point to the heel or ...To assess the meshing quality of spiral bevel gears,the static meshing characteristics are usually checked under different contact paths to simulate the deviation in the footprint from the design point to the heel or toe of the gear flank caused by the assembly error of two gear axes.However,the effect of the contact path on gear dynamics under lubricated conditions has not been reported.In addition,most studies regarding spiral bevel gears disregard the lubricated condition because of the complicated solutions of mixed elastohydrodynamic lubrication(EHL).Hence,an analytical friction model with a highly efficient solution,whose friction coefficient and film thickness predictions agree well with the results from a well-validated mixed EHL model for spiral bevel gears,is established in the present study to facilitate the study of the dynamics of lubricated spiral bevel gears.The obtained results reveal the significant effect of the contact path on the dynamic response and meshing efficiency of gear systems.Finally,a comparison of the numerical transmission efficiency under different contact paths with experimental measurements indicates good agreement.展开更多
基金Funded by the National Natural Science Foundation of China (No.51075237)the National Basic Research Program of China (No.2009CB724402)+3 种基金the Taishan Scholar Program of Shandong Provincethe Outstanding Young Scholar Science Foundation of Shandong (No.JQ200917)the National Natural Science Foundation of Shandong (No.ZR2010EZ002)National High Technology Research and Development Program (No.2009AA044303)
文摘MoS2/Zr composite films were deposited on the cemented carbide YT14 （WC＋14%TiC＋6%Co） by medium-frequency magnetron sputtered and coupled with multi-arc ion plated techniques.The influence of negative bias voltage on the composite film properties,including adhesion strength,micro-hardness,thickness and tribological properties were investigated.The results showed that proper negative bias voltage could significantly improve the mechanical and tribological properties of composite films.The effects of negative bias voltage on film properties were also put forward.The optimal negative bias voltage was -200 V under this experiment conditions.The obtained composite films were dense,the adhesion strength was about 60 N,the thickness was about 2.4 μm,and the micro-hardness was about 9.0 GPa.The friction coefficient and wear rate was 0.12 and 2.1×10-7 cm3/N·m respectively after 60 m sliding operation against hardened steel under a load of 20 N and a sliding speed of 200 rev·min-1.
基金supported by the National Natural Science Foundation of China(Grant No.11171208)the Natural Science Foundation of Shanxi Province,China(Grant No.2013011022-6)
文摘An interpolating reproducing kernel particle method for two-dimensional （2D） scatter points is introduced. It elim- inates the dependency of gridding in numerical calculations. The interpolating shape function in the interpolating repro- ducing kernel particle method satisfies the property of the Kronecker delta function. This method offers a mathematics basis for recognition technology and simulation analysis, which can be expressed as simultaneous differential equations in science or project problems. Mathematical examples are given to show the validity of the interpolating reproducing kernel particle method.
基金The present study was founded by the National Natural Science Foundation of China(Grant Nos.52005047 and 51875369)Natural Science Basic Research Plan in Shaanxi Province of China(Grant Nos.2020JQ-367 and 2020JQ-345)+1 种基金China Postdoctoral Science Foundation(Grant No.2020M672129)and the Fundamental Research Funds for the Central Universities,CHD(Grant No.300102250301).
文摘To assess the meshing quality of spiral bevel gears,the static meshing characteristics are usually checked under different contact paths to simulate the deviation in the footprint from the design point to the heel or toe of the gear flank caused by the assembly error of two gear axes.However,the effect of the contact path on gear dynamics under lubricated conditions has not been reported.In addition,most studies regarding spiral bevel gears disregard the lubricated condition because of the complicated solutions of mixed elastohydrodynamic lubrication(EHL).Hence,an analytical friction model with a highly efficient solution,whose friction coefficient and film thickness predictions agree well with the results from a well-validated mixed EHL model for spiral bevel gears,is established in the present study to facilitate the study of the dynamics of lubricated spiral bevel gears.The obtained results reveal the significant effect of the contact path on the dynamic response and meshing efficiency of gear systems.Finally,a comparison of the numerical transmission efficiency under different contact paths with experimental measurements indicates good agreement.
