论文部分内容阅读
采用自行研制的流变装置进行瞬态流变试验 ,研究了剪切停留对液固温区不同初生α相形态A35 6合金的组织变化及其瞬态流变行为的影响 .结果表明 ,在相同的剪切条件下 ,随剪切停留时间的增加 ,瞬时峰值表观粘度增加 ,说明剪切停留期间半固态合金初生α相形态发生了变化 ;对半固态合金初生相形态观察发现 ,剪切停留促使初生相发生了“团聚”或“合并” ,而且初生相形态变化的程度取决于剪切停留时间和初生相的退化程度 .对试验结果进行曲线拟合 ,得到了描述半固态合金峰值表观粘度和剪切停留时间的瞬态流变方程
The transient rheological tests were carried out with a rheometer which was developed by ourselves to study the effect of shear-residence on the microstructure and transient rheological behavior of different primary α-phase A356 alloys in the liquid-solid temperature region. The results show that in the same , The apparent viscosity of the instantaneous peak increases with the increase of shear residence time, which indicates that the morphology of the primary α phase in the semi-solid alloy during shear-residence changes. The morphological observation of the primary phase of the semi-solid alloy shows that the shear arrest Which led to the occurrence of “reunion” or “merging” of the primary phase, and the degree of change in morphology of the primary phase was determined by the shear residence time and the degree of degeneration of the primary phase. The curve fitting of the test results obtained the peak apparent Viscosity and shear dwell time of the transient rheological equation