| Solidification behavior and microstructure properties of alloy are closely related to melt structure of alloy. Currently, the main methods to improve the alloysalloying performance are alloying, rapid solidification and deformation heat treatment method. It is still empirical of using melt superheat treatment process to induce the structural change of and to improve the solidification process solidification structure and performance of alloy melt.In this paper, three typical industrial wear-resistant alloy(SnSb11Cu6、Al-20Sn、QAl10-4-4) are used as study objects. Variability of the melt structure was studied by changing melt resistivity. The influence of temperature induced melt structural transformation on solidification microstructure and mechanical properties by melt superheating treatment of three alloy(SnSb11Cu6、Al-20Sn、and QAl10-4-4) was investigated. Research contents and conclusions are as follows:Firstly, by exploring temperature and time dependence of melt electrical resistivities on alloy (SnSb11Cu6、Al-20Sn、QAI10-4-4), experiments showed that with increasing temperature, the alloy occurred abnormal mutation of different characteristics within a certain temperature range.Secondly, through the analysis of solidification microstructure observation, EDS and XRD test comparison in the alloy (SnSb11Cu6、 Al-20Sn、QAI10-4-4) solidification experiments, we found that alloy solidification structure was obviously refined, and the distribution of alloy phase were more uniform by melt superheating treatment. Analysis believed that this may be solid-type atomic cluster structure of melt was broken at high temperature thermal, which had a certain influence on the solidification structure of the alloy.Thirdly, alloy (SnSb11Cu6、Al-20Sn、QAl10-4-4) friction and wear experimental comparison showed that the friction and wear properties of the alloy was significantly improved, the coefficient of friction was significantly reduced, the amount of wear and tear became smaller, and the hardness increased by superheating treatment. Alloy solidification structure refinement and uniform distribution network after melt superheat largely reduced the deep plow marks during friction and wear and the occurrence of adhesion. At the same time, mesh structure can store lubricating oil, which would improve the wear resistance of the alloy.Fourth, tensile creep experiment under certain conditions of temperature and applied stress of SnSb11Cu6, QAl10-4-4 found that the first stage of creep alloy samples shortened, the rate of steady creep stage significantly reduced, the steady-state phase time and creep time prolonged.Creep deformation amount was significantly less than the untreated melt structural transformation of alloy in the process of the whole experiment. It could fully explain that the creep properties of the alloy have been significantly improved after melt structural transformation. |
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