硬质合金强度随温度的变化及失效机理的研究Effect of temperature on bending strength and failure mechanism of cemented carbide
黄道远,易丹青,刘会群,蔡志刚,刘瑞,李荐
摘要(Abstract):
研究了温度对3555和471硬质合金抗弯强度的影响。结果表明,3555和471硬质合金的抗弯强度在室温至300℃的范围内基本保持不变,在300~400℃开始下降,在400~500℃范围内剧烈下降,在500~600℃范围内下降变缓,在600~700℃时,抗弯强度值出现一个平台,比室温时强度降低30%左右。这是由于高温下合金的软化,hcpγ→fccγ相变,W、C在粘结相中的固溶以及热应力共同作用的结果。3540和3475合金高温下断面的粗糙度降低,孔洞增多,沿晶断裂比例增加。高温下合金表面发生氧化,形成疏松的垂直于表面生长的柱状晶氧化层,3555抗氧化能力比471合金高。
关键词(KeyWords): 硬质合金;高温;抗弯强度;失效
基金项目(Foundation):
作者(Author): 黄道远,易丹青,刘会群,蔡志刚,刘瑞,李荐
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