【摘要】 本文研究了自生复合Ａｌ＿（１１）Ｌａ＿３／Ａｌ共晶材料从室温到６７３Ｋ时的轴向拉伸性能和轴向拉伸断裂机制。结果表明：在Ｇ＝７００Ｋ／ｃｍ、Ｒ＝１１．１μｍ／ｓ的定向凝固条件下，该材料轴向拉伸性能在室温时为２６０ＭＰａ、在６７３Ｋ时为２６５ＭＰａ。对拉伸过程的动态观察和断口形貌的分析表明：自生复合Ａｌ＿（１１）Ｌａ＿３／Ａｌ共晶材料在室温到６７３Ｋ温度范围内，其轴向拉伸断裂机制相同：纤维相Ａｌ＿（１１）Ｌａ＿３的断裂是整个共晶体断裂的控制机制：其轴向拉伸的断裂模型为：弹性变形、裂纹萌生、界面脱粘、搭桥过程、宏观断裂。更多还原

【Abstract】 The axial tensile properties and fracture mechanism of in-situcompoite Al₁₁La₃/Al have been investigated in the temperature range of 293-693K. The result is that the tensile strength reaches 260MPa at the normaltemperature and :265MPa at 693K for the alloy under the condition of directi-onal solidification（G=700K/cm,P=11.1μm/s）.With the study on:tho tensileDroces;and the fracture morphol ogy,the in-situ composite Al₁₁La₃/Al hasthe same axial tensile fracture mechanism in the temoerature range of 293-693K. The fracture of fiber phase Al₁₁La₃ is the critical factor for thefracture of the comoosite. The fracture model of tensile test is:elasticdeformation,cracks neucleation, interface separation cracks propagation andmacrofracture.更多还原