摘要
采用砂型铸造方法,制备了Mg-11.2Gd-3.5Y-0.46Zr合金,通过正交试验方法优化了合金热处理工艺。结果表明,合金在525℃×10h+24 0℃×9h热处理工艺下,得到最佳力学性能:抗拉强度σb360MPa、屈服强度σs305MPa,延伸率δ54.0%。背散射电子扫描结果显示,嵌入基体的高稀土含量的Mg-RE中间相存在于铸态、固溶态及时效态,对合金的强化作用明显;T6状态下,合金的断裂机理以准解理断裂为主。
In order to optimize the tensile property of Mg-Gd-Y-Zr alloy,Mg-11.2Gd-3.5Y-0.46Zr was prepared for orthogonal experiment.The results showed that the optimal heat treatment was 525℃×10h+240℃×9h,the tensile strength,yield strength and elongation was 360Mpa,305Mpa,4% respectively.SEM fracture observation results suggested that the second-phase precipitates,which were Mg-RE intermediate phase,existed in as-cast(F),solution-treated(T4) and artificially-aged(T6) conditions.In optimal T6 condition,the fracture mechanism was mainly cleavage fracture.
出处
《航天制造技术》
2011年第6期15-18,22,共5页
Aerospace Manufacturing Technology
