Consturuction of Analysis System for Deformation Behavior during Solidification of Metallic Materials

金属材料凝固过程变形行为分析系统的构建

基本信息

批准号：
04555161
负责人：
UMEDA Takateru
金额：
$ 7.1万
依托单位：
The University of Tokyo
依托单位国家：
日本
项目类别：
Grant-in-Aid for Developmental Scientific Research (B)
财政年份：
1992
资助国家：
日本
起止时间：
1992 至 1993
项目状态：
已结题

项目摘要

For metals processings which aim at higher quality and higher productivity, solidification crack is one of the worst obstruction variables to overcome. Therefore we investigated the deformation behavior of carbon steels and copper-tin alloys during and after solidification. We carried out high temperature tensile tests for samples which have higher carbon contents to 0.8wt% and for samples which have higher sulfur contents. We also investigated the influence of strain rate on mechanical properties during solidification of 0.6wt%C samples. As a result of the high temperature tensile test, ZST(Zero Strength Temperature) was determined to be the temperature which corresponds to the solid fraction of about 0.7 for both high carbon samples and high sulfur samples as is same with the previous experimental results. On the contrary little ductility was observed even below the temperature at which solidification completes according to the numerical analysis, and ZDT could not be determined. The reason why ZDT does not correspond to the solid fraction of 1 seems to be the low purity of the samples compared with the previously tested samples. For example, having both sulfur and phosphorus are more contained for about. However the mechanism of causing the ZDT drop remains unexplained. The increase of strain rate gave rise of the tensile strength, and around 5mm displacement was measured under strain rate of 10^<-3>/s though little displacement was observed under strain rate of 10^0-10^<-2>/s. Consequently it is concluded that the mechanical properities depend on the strain rate even in the solidification temperature range.As for copper-tin alloys deformation behavior under strain tate of 10^0-10^<-4>/s was measured at the temperature range below the solidus. Regression equations for tensile strength, flow stress and elongation are obtained in relation to testing temperature, strain rate and/or strain.

对于以更高质量和更高生产率的金属处理，固化裂纹是要克服的最严重的阻塞变量之一。因此，我们研究了在凝固过程和之后碳钢和铜锡合金的变形行为。我们对碳含量较高至0.8 wt％的样品以及具有较高硫含量的样品进行了高温拉伸测试。我们还研究了应变速率对0.6wt％C样品固化过程中机械性能的影响。由于高温拉伸试验，确定ZST（零强度温度）是高碳样品和高硫样品的固体分数，与先前的实验结果相同。相反，几乎没有延展性，甚至低于根据数值分析完成凝固完成的温度，并且无法确定ZDT。与先前测试的样品相比，ZDT不对应于1的固体分数似乎是样品的低纯度。例如，拥有硫和磷的同时更容易包含。然而，引起ZDT滴剂的机制仍无法解释。应变速率的增加产生了拉伸强度的增加，并且在应变速率为10^<-3>/s的情况下测量了大约5mm的位移，尽管在应变速率下很少观察到10^0-10^<-2>/s的位移。因此得出的结论是，机械的正当性即使在固化温度范围内也取决于应变速率。在应变泰特（10^0-10^<-4>/s）下，在固体以下的温度范围内测量了铜锡合金变形行为。与测试温度，应变速率和/或应变有关，获得了拉伸强度，流动应力和伸长的回归方程。