The wear patterns and wear mechanisms of solid cemented carbide are analyzed in high-speed milling of aluminum alloy. Results show that the dominant wear patterns are coating damage, crater wear, micro-chipping, break...The wear patterns and wear mechanisms of solid cemented carbide are analyzed in high-speed milling of aluminum alloy. Results show that the dominant wear patterns are coating damage, crater wear, micro-chipping, breakage, and so on. The main wear mechanisms are adhesion, diffusion and fatigue. Compared with conventional speed machining, the effect and impact of thermal-dynamical coupling field play an important role in the cutting tool wear in high-speed milling of aluminum alloy.展开更多
A study was carried out to evaluate abrasion of shoe-sole for subjects with different running gait. A 3 dimensional （3D） scanning approach together with a commercial software, CloudCompare Mesh Cloud Comparison was ...A study was carried out to evaluate abrasion of shoe-sole for subjects with different running gait. A 3 dimensional （3D） scanning approach together with a commercial software, CloudCompare Mesh Cloud Comparison was utilized for this study. In CloudCompare, a grid system and colored scale was applied to identify the region and extend of abrasion of the shoe-sole. This study clearly showed the extent of abrasion on regions of shoe-sole identified from the colored scale. This paper was done with kind support from Asics Institute for Sports Science, Kobe, Japan and Institute for Sport Research （ISR-NTU）.展开更多
Laser gas nitriding （LGN） is a common surface modification method to enhance the wear resistance of titanium （Ti） alloys, which are known to have poor tribological properties. In the present study, a titanium nitr...Laser gas nitriding （LGN） is a common surface modification method to enhance the wear resistance of titanium （Ti） alloys, which are known to have poor tribological properties. In the present study, a titanium nitride （TIN） grid network was fabricated on the surface of nickel titanium （NiTi） by LGN. The laser processing parameters were selected to achieve nitriding without surface melting and hence to＇maintain a smooth surface finish. The characteristics of the grid-nitrided samples were investigated by scanningelectron microscopy, X-ray diffractometry, optical microscopy, 2-D profilometry, contact angle measurements and nanoindentation. The wear resistance of the nitrided samples was evaluated using reciprocating wear test against ultra-high-molecular-weight polyethylene （UHMWPE） in Hanks＇ solution. The results indicate that the wear rates of the grid-nitrided samples and the UHMWPE counter-body in the wear pair are both significantly reduced. The decrease in wear rates can be attributed to the combination of a hard TiN grid and a soft NiTi substrate. In Hanks＇ solution, the higher hydrophilicity of the nitrided samples also contributes to the better performance in wear test against hydrophobic UHMWPE.展开更多
文摘The wear patterns and wear mechanisms of solid cemented carbide are analyzed in high-speed milling of aluminum alloy. Results show that the dominant wear patterns are coating damage, crater wear, micro-chipping, breakage, and so on. The main wear mechanisms are adhesion, diffusion and fatigue. Compared with conventional speed machining, the effect and impact of thermal-dynamical coupling field play an important role in the cutting tool wear in high-speed milling of aluminum alloy.
文摘A study was carried out to evaluate abrasion of shoe-sole for subjects with different running gait. A 3 dimensional （3D） scanning approach together with a commercial software, CloudCompare Mesh Cloud Comparison was utilized for this study. In CloudCompare, a grid system and colored scale was applied to identify the region and extend of abrasion of the shoe-sole. This study clearly showed the extent of abrasion on regions of shoe-sole identified from the colored scale. This paper was done with kind support from Asics Institute for Sports Science, Kobe, Japan and Institute for Sport Research （ISR-NTU）.
基金supported by the Research Grants Council of the Hong Kong Special Administrative Region,China(Project No.PolyU524210E)
文摘Laser gas nitriding （LGN） is a common surface modification method to enhance the wear resistance of titanium （Ti） alloys, which are known to have poor tribological properties. In the present study, a titanium nitride （TIN） grid network was fabricated on the surface of nickel titanium （NiTi） by LGN. The laser processing parameters were selected to achieve nitriding without surface melting and hence to＇maintain a smooth surface finish. The characteristics of the grid-nitrided samples were investigated by scanningelectron microscopy, X-ray diffractometry, optical microscopy, 2-D profilometry, contact angle measurements and nanoindentation. The wear resistance of the nitrided samples was evaluated using reciprocating wear test against ultra-high-molecular-weight polyethylene （UHMWPE） in Hanks＇ solution. The results indicate that the wear rates of the grid-nitrided samples and the UHMWPE counter-body in the wear pair are both significantly reduced. The decrease in wear rates can be attributed to the combination of a hard TiN grid and a soft NiTi substrate. In Hanks＇ solution, the higher hydrophilicity of the nitrided samples also contributes to the better performance in wear test against hydrophobic UHMWPE.
