The effect of grain refiner, Mn and Sn additions on the sliding wear behavior of A356 aluminum alloys was investigated. The microstructure and worn surfaces of the studied alloys were characterized by optical microsc...The effect of grain refiner, Mn and Sn additions on the sliding wear behavior of A356 aluminum alloys was investigated. The microstructure and worn surfaces of the studied alloys were characterized by optical microscopy（OM）, scanning electron microscopy（SEM）, and transmission electron microscopy（TEM）. The experimental results indicate that the alloy refined by Al-5Ti-B alloy exhibits equiaxed α（Al） dendrites and performs better wear resistance compared with the alloy without the grain refiner. Moreover, the addition of Mn can change the β-Al5 Fe Si phase to α-Al（Mn,Fe）Si phase and reduce the possibility of crack formation, thus improving the wear resistance. Sn added to A356 aluminum alloy forms Mg2 Sn precipitates after heat treatment. Therefore, the unrealizable precipitation hardening Mg2 Si phase and the softening β-Sn phase can reduce the hardness of the alloy, and finally reduce the wear resistance.展开更多
Tribological behaviour of the die-cast AZ71E magnesium alloy was investigated in an applied load range of 10-50 N at high temperatures under dry sliding conditions using a pin-on-disc wear testing machine. The results...Tribological behaviour of the die-cast AZ71E magnesium alloy was investigated in an applied load range of 10-50 N at high temperatures under dry sliding conditions using a pin-on-disc wear testing machine. The results indicate that the wear rate increases with the increase of applied load and sliding distance, whereas the friction coefficient decreases with the increase of applied load. Scanning electron microscopy and optical microscopy studies on the worn surfaces and sub-surfaces show that the predominant wear mechanism is abrasion at low applied loads. The mild delamination wear accompanying with adhesion wear is the predominant wear mechanism under high applied loads at 150 ℃, whereas the severe delamination and melting wear are the predominant wear mechanisms under high applied load at 200 ℃. An investigation of the microstructure, thermal stability and tensile properties at high temperatures, using the optical microscopy, X-ray diffraction, differential scanning calorimetry, shows that the dominant secondary phase in AZ71E alloy, Al11Ce3, leads to the improvement in the tensile and elongation properties of alloy at high temperatures, which results in the improvement in the anti wear performance.展开更多
文摘The effect of grain refiner, Mn and Sn additions on the sliding wear behavior of A356 aluminum alloys was investigated. The microstructure and worn surfaces of the studied alloys were characterized by optical microscopy（OM）, scanning electron microscopy（SEM）, and transmission electron microscopy（TEM）. The experimental results indicate that the alloy refined by Al-5Ti-B alloy exhibits equiaxed α（Al） dendrites and performs better wear resistance compared with the alloy without the grain refiner. Moreover, the addition of Mn can change the β-Al5 Fe Si phase to α-Al（Mn,Fe）Si phase and reduce the possibility of crack formation, thus improving the wear resistance. Sn added to A356 aluminum alloy forms Mg2 Sn precipitates after heat treatment. Therefore, the unrealizable precipitation hardening Mg2 Si phase and the softening β-Sn phase can reduce the hardness of the alloy, and finally reduce the wear resistance.
基金Project (KLMT201107) supported by the Key Laboratory of Manufacture and Test Techniques for Automobile Parts (Ministry of Education), China
文摘Tribological behaviour of the die-cast AZ71E magnesium alloy was investigated in an applied load range of 10-50 N at high temperatures under dry sliding conditions using a pin-on-disc wear testing machine. The results indicate that the wear rate increases with the increase of applied load and sliding distance, whereas the friction coefficient decreases with the increase of applied load. Scanning electron microscopy and optical microscopy studies on the worn surfaces and sub-surfaces show that the predominant wear mechanism is abrasion at low applied loads. The mild delamination wear accompanying with adhesion wear is the predominant wear mechanism under high applied loads at 150 ℃, whereas the severe delamination and melting wear are the predominant wear mechanisms under high applied load at 200 ℃. An investigation of the microstructure, thermal stability and tensile properties at high temperatures, using the optical microscopy, X-ray diffraction, differential scanning calorimetry, shows that the dominant secondary phase in AZ71E alloy, Al11Ce3, leads to the improvement in the tensile and elongation properties of alloy at high temperatures, which results in the improvement in the anti wear performance.
