The tribological behaviours of aluminium-based bearing alloys with different compositions, forged and heat treated materials, were investigated in oil lubricated conditions. Tested materials were Al-8.5Si-3.5Cu and Al...The tribological behaviours of aluminium-based bearing alloys with different compositions, forged and heat treated materials, were investigated in oil lubricated conditions. Tested materials were Al-8.5Si-3.5Cu and Al-15Pb-3.7Cu-1.5Si-1.1Fe. The effects of hardness, heat treatment and forging on wear behaviours of the tested materials were investigated. In forging process, 10%-20%strains were applied. Heat treatment (T6) was performed to the materials. The wear tests of all specimens were performed with a pin-on-disc wear test machine. Forging process increased hardness value of the tested materials. A forging strain of 10%-20%has no significant effect on mass loss.展开更多
The expediency of development of one of the newest highly effective radiation-protective materials—layered composites of “light metal/heavy metal” type is substantiated. The characteristics of the internal architec...The expediency of development of one of the newest highly effective radiation-protective materials—layered composites of “light metal/heavy metal” type is substantiated. The characteristics of the internal architecture of composites of Al/Pb type made by consecutive application of vacuum and normal atmospheric rolling are adduced. The differences between the radioisotope and accelerating techniques of experimental testing of radiation-protective properties of materials are described. The results of the testing of composites and the influence of their structure on radiation-protective properties of the investigated materials are characterized. It is shown that the radiation-protective efficiency of composites certain structures may be 30% - 40% higher than the aluminum. This gives the opportunity to reduce the weight of radiation-protective structure at preservation of effectiveness of protection at aluminum level, or to increase the effectiveness of protection at constant weight of this structure.展开更多
Composite powder of Al-20Pb alloy was prepared by mechanical milling. The microstructure of the powder was analyzed by electronic probe microscopy. Compaction of the powder was also performed. The results show that af...Composite powder of Al-20Pb alloy was prepared by mechanical milling. The microstructure of the powder was analyzed by electronic probe microscopy. Compaction of the powder was also performed. The results show that after ball milling for 6h, the composite powder possesses fine laminar structures, good plasticity, and it is easy to densify. By extruding the composite powder ball milled for 6h with an extrusion ratio of 4, the Al-20Pb alloy with a relative density of 97%, a porosity of 3% and fine and homogenously distributed Pb phase was obtained. The results of wear and friction test indicate that a lubricating layer with a friction coefficient of about 0.4 forms on the friction surface, and the wear model is slight oxidation wear.展开更多
b The discharge performance of Mg-Al-Pb-La anode was investigated by electrochemical techniques and compared withthat of Mg-Al-Pb alloy. The results indicate that the Mg-Al-Pb-La anode provides enhanced corrosion resi...b The discharge performance of Mg-Al-Pb-La anode was investigated by electrochemical techniques and compared withthat of Mg-Al-Pb alloy. The results indicate that the Mg-Al-Pb-La anode provides enhanced corrosion resistance at open circlepotential, and exhibits better discharge activity than the Mg-Al-Pb alloy. The utilization efficiency of Mg-Al-Pb-La anode ishigher than that of commercial Mg-Al-Zn (AZ) and Mg-Al-Mn (AM) alloys. A single Mg-air battery with Mg-Al-Pb-La alloy asthe anode and air as the cathode has an average discharge potential of 1.295 V and a discharge capacity of 1370 mA·h/g duringdischarge at 10 mA/cm2, which is higher than that of batteries using Mg-Li anodes. The enhancement in discharge performance ofthe Mg-Al-Pb-La anode is caused by its modified microstructure, which reduces the self-corrosion and accelerates the spalling ofoxidation products during battery discharge. Furthermore, the dissolution mechanism of Mg-Al-Pb-La anode during the dischargeprocess was analyzed.展开更多
文摘The tribological behaviours of aluminium-based bearing alloys with different compositions, forged and heat treated materials, were investigated in oil lubricated conditions. Tested materials were Al-8.5Si-3.5Cu and Al-15Pb-3.7Cu-1.5Si-1.1Fe. The effects of hardness, heat treatment and forging on wear behaviours of the tested materials were investigated. In forging process, 10%-20%strains were applied. Heat treatment (T6) was performed to the materials. The wear tests of all specimens were performed with a pin-on-disc wear test machine. Forging process increased hardness value of the tested materials. A forging strain of 10%-20%has no significant effect on mass loss.
文摘The expediency of development of one of the newest highly effective radiation-protective materials—layered composites of “light metal/heavy metal” type is substantiated. The characteristics of the internal architecture of composites of Al/Pb type made by consecutive application of vacuum and normal atmospheric rolling are adduced. The differences between the radioisotope and accelerating techniques of experimental testing of radiation-protective properties of materials are described. The results of the testing of composites and the influence of their structure on radiation-protective properties of the investigated materials are characterized. It is shown that the radiation-protective efficiency of composites certain structures may be 30% - 40% higher than the aluminum. This gives the opportunity to reduce the weight of radiation-protective structure at preservation of effectiveness of protection at aluminum level, or to increase the effectiveness of protection at constant weight of this structure.
文摘Composite powder of Al-20Pb alloy was prepared by mechanical milling. The microstructure of the powder was analyzed by electronic probe microscopy. Compaction of the powder was also performed. The results show that after ball milling for 6h, the composite powder possesses fine laminar structures, good plasticity, and it is easy to densify. By extruding the composite powder ball milled for 6h with an extrusion ratio of 4, the Al-20Pb alloy with a relative density of 97%, a porosity of 3% and fine and homogenously distributed Pb phase was obtained. The results of wear and friction test indicate that a lubricating layer with a friction coefficient of about 0.4 forms on the friction surface, and the wear model is slight oxidation wear.
基金Project(2015JC3004)supported by the Science and Technology Plan of Hunan Province,ChinaProject(2016JJ2147)supported by the Natural Science Foundation of Hunan Province,ChinaProject(51401243)supported by the National Natural Science Foundation of China
文摘b The discharge performance of Mg-Al-Pb-La anode was investigated by electrochemical techniques and compared withthat of Mg-Al-Pb alloy. The results indicate that the Mg-Al-Pb-La anode provides enhanced corrosion resistance at open circlepotential, and exhibits better discharge activity than the Mg-Al-Pb alloy. The utilization efficiency of Mg-Al-Pb-La anode ishigher than that of commercial Mg-Al-Zn (AZ) and Mg-Al-Mn (AM) alloys. A single Mg-air battery with Mg-Al-Pb-La alloy asthe anode and air as the cathode has an average discharge potential of 1.295 V and a discharge capacity of 1370 mA·h/g duringdischarge at 10 mA/cm2, which is higher than that of batteries using Mg-Li anodes. The enhancement in discharge performance ofthe Mg-Al-Pb-La anode is caused by its modified microstructure, which reduces the self-corrosion and accelerates the spalling ofoxidation products during battery discharge. Furthermore, the dissolution mechanism of Mg-Al-Pb-La anode during the dischargeprocess was analyzed.