摘要
采用拉伸试验、金相分析、SEM和TEM等方法测试和分析ZK60镁合金在挤压态、T5、T6及双级时效态下合金的力学性能和显微组织。结果表明,经过T5时效处理后,合金屈服强度和伸长率提高,而T6时效处理对合金的强度和伸长率影响不大,双级时效可明显提高合金的强度,但是伸长率稍有降低。经T5、T6时效后,合金中析出大量细小弥散的β1′相,为合金的主要强化相,双级时效能提高β1′相的析出密度,从而提高合金的强度。ZK60挤压态和T5态合金的断裂方式为混合型断裂,而T6和双级时效的断裂方式为解理断裂。
The microstructure and mechanical properties of ZK60 magnesium alloy in as-extruded,T5,T6 and double aging states were investigated by tensile test,optical microscopy,SEM and TEM.The results show that T5 treatment can obviously increase the yield strength and elongation of ZK60 magnesium alloy,while T6 treatment has negligible effect on the variation of strength and elongation.Double aging is the most effective for improving the strength,while slightly decreases the elongation.After T5,T6,the main strengthening phase of dispersive β′1 phase precipitates within the alloy homogenously,and double aging can significantly increase the density of β′1 phase,which results in the obvious increment in strength of ZK60 magnesium alloy.The fracture for as-extruded and T5 state ZK60 alloy is a mixed type,and that for T6 state and double aging is cleavage fracture.
出处
《金属热处理》
CAS
CSCD
北大核心
2011年第1期52-56,共5页
Heat Treatment of Metals
