本文详细考察了国产LC4合金在形变热处理各工艺阶段的组织及性能变化,用扫描电镜研究了材料的断口特征,并用断口斜剖法观察了断裂形式和金相组织的对应关系。结果表明,形变热处理可以显著提高LC4合金的强度,并降低该合金的沿晶断裂倾向。这种有利作用与该处理引起的材料晶界及晶内组织结构的改善有关。 In this paper, the microstructures and properties of domestic LC4 alloys during various heat treatment stages were investigated in detail. The fracture characteristics of the materials were studied by SEM. The corresponding relationship between the fracture morphology and the microstructure was observed by fracture-section method. The results show that the heat treatment can significantly improve the strength of LC4 alloy and reduce the intergranular fracture tendency of the alloy. This favorable effect is related to the grain boundary and the intragranular structure of the material caused by this treatment.