Dry sliding wear tests on as-cast and cast+T6 Mg-11Y-5Gd-2Zn magnesium alloys were performed using a ball-on-plate configuration. The wear rates were measured within a load range of 3-15 N, sliding speed range of 0.0...Dry sliding wear tests on as-cast and cast+T6 Mg-11Y-5Gd-2Zn magnesium alloys were performed using a ball-on-plate configuration. The wear rates were measured within a load range of 3-15 N, sliding speed range of 0.03-0.24 m/s, test temperature range of 25-200 °C and at a constant sliding distance of 400 m. The wear tracks, worn surfaces and wear debris of the alloys were analyzed using scanning electron microscope (SEM). The results show that the wear rate of the alloys increases almost linearly with increasing applied load and decreases with increasing sliding speed. The wear rate of the as-cast alloy is higher than that of the cast+T6 alloy. The amount of Mg12Y1Zn1 phase, surface oxidation and retained wear debris affect the wear rate. The dominant wear mechanisms under the test condition are abrasion and plastic deformation.展开更多
Focusing on the speed control problem, this paper presents a study on the stick slip phenomena of cable driven by pipe robot and the critical conditions of stick slip. By dynamics simulation and field experiments, the...Focusing on the speed control problem, this paper presents a study on the stick slip phenomena of cable driven by pipe robot and the critical conditions of stick slip. By dynamics simulation and field experiments, the theoretical analysis has been proved to be practical and valid. The result is of considerable theoretical value in the speed control for pipe robot on receiving and putting line.展开更多
基金Project (51074106) supported by the National Natural Science Foundation of ChinaProject (2009AA033501) supported by the Hi-Tech Research and Development Program of China+1 种基金Project (09JC1408200) supported by the Science and Technology Commission of Shanghai Municipality, ChinaProject (20100480586) supported by Postdoctoral Science Foundation of China
文摘Dry sliding wear tests on as-cast and cast+T6 Mg-11Y-5Gd-2Zn magnesium alloys were performed using a ball-on-plate configuration. The wear rates were measured within a load range of 3-15 N, sliding speed range of 0.03-0.24 m/s, test temperature range of 25-200 °C and at a constant sliding distance of 400 m. The wear tracks, worn surfaces and wear debris of the alloys were analyzed using scanning electron microscope (SEM). The results show that the wear rate of the alloys increases almost linearly with increasing applied load and decreases with increasing sliding speed. The wear rate of the as-cast alloy is higher than that of the cast+T6 alloy. The amount of Mg12Y1Zn1 phase, surface oxidation and retained wear debris affect the wear rate. The dominant wear mechanisms under the test condition are abrasion and plastic deformation.
文摘Focusing on the speed control problem, this paper presents a study on the stick slip phenomena of cable driven by pipe robot and the critical conditions of stick slip. By dynamics simulation and field experiments, the theoretical analysis has been proved to be practical and valid. The result is of considerable theoretical value in the speed control for pipe robot on receiving and putting line.