LIU Zongchang Baotou Iron and Steel University
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China LIU Zongchang Associate Professor
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Division of Materials and Heat Treatment
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Baotou Iron and Steel University
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Baotou
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China
金属学报(英文版)
A mechanism of intergranular fracture of as-quenched martensite in high carbon steels has been proposed.When coarse grains of austenite transform to martensite,the grain plays a role of the unit of volume dilation,inhomogeneous strains necessarily produce and local microscop- ic stress concentrations create at grain boundaries.This reduces the intergration of the grains, sometimes intergranular cracks may produce.Under the action of first kind hardening stress or external force,the intergranular cracks propagated along the grain boundaries will form. This results in the candy-like fracture.
关键词:
as-quench martensite
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null
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刘宗昌
金属学报
提出马氏体沿晶断裂机制:粗大奥氏体晶粒转变为马氏体时,以晶粒为体积膨胀单元,必然产生不均匀应变,在晶界区形成显微局部应力,甚至产生应力集中,削弱晶界结合,有时出现微裂缝,在淬火第一类应力(或外力)作用下,形成沿原奥氏体晶界扩展的沿晶裂纹和冰糖状断口。
关键词:
淬火马氏体
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intergranular fracture
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inhomogeneous strain
