镁合金热裂行为研究的测试方法探讨

针对镁合金的特点，就合金热裂行为研究的测试方法进行了实验研究和分析。用热裂行为测试系统测量合金凝固过程中的温度、线收缩和收缩应力，用铸造热分析系统分析铸造凝固条件下的相析出，这为研究合金的热裂形成机理提供了重要的实验手段。采用热裂环法可以有效地评价合金的热裂倾向性，而等长度试棒法(无论金属型还是砂型)则不适于测试镁合金。

A Discussion of Testing Methods for Hot-tearing Behavior of Magnesium Alloys

Based on the characteristics of magnesium alloys, testing methods for research on hot-tearingwere experimentally investigated and analyzed. Temperature,linear shrinkage and shrinkage power during solidification of magnesium alloys were measured with a testing system for hot-tearing behavior. The phase precipitated under the commercial casting solidification condition was analyzed with a thermo-analysis system. These methods can provide important experimental support to understanding the hot-tearing mechanism of magnesium alloys. Hot-tearing susceptibility of magnesium alloys can be efficiently evaluated with crack-ring method. However,the same-length test bar method (permanent mold or sand mold) was not suitable for testing of magnesium alloys.