论文部分内容阅读
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。
Tensile test, metallographic analysis, SEM and TEM were used to test and analyze the mechanical properties and microstructure of ZK60 magnesium alloy in the as-extruded, T5, T6 and two-stage aging states. The results show that after T5 aging, the yield strength and elongation of the alloy increase, while the T6 aging treatment has little effect on the strength and elongation of the alloy, two-stage aging can significantly improve the strength of the alloy, but the elongation decreased slightly. After aging of T5 and T6, a large amount of fine and dispersed β1 ’phase precipitated in the alloy, which is the main strengthening phase of the alloy, and the double-stage aging improves the precipitation density of the β1’ phase and improves the strength of the alloy. The fracture mode of ZK60 extruded state and T5 alloy is mixed fracture, while the fracture mode of T6 and two-stage aging is cleavage fracture.