应变速率对QT450-10球墨铸铁热塑性及石墨颗粒的影响  

Influence of strain rate on hot plasticity and graphite particles morphology of QT450-10 spheroidal graphite cast iron

作　　者：齐凯[1] 白富栋[1] 滕海涛[1] 黄文初 江珍雅 王之新[1] 李廷举[1] 

机构地区：[1]大连理工大学材料科学与工程学院材料加工工程系,辽宁大连116085 [2]山东莱芜钢铁股份有限公司,山东莱芜271104 [3]国家电机及机械零部件产品质量监督检验中心,浙江台州318000

出　　处：《材料热处理学报》2010年第4期86-89,94,共5页Transactions of Materials and Heat Treatment

基　　金：国家自然科学基金(50674018)

摘　　要：利用Gleeble-1500热模拟机研究了QT450-10球墨铸铁在不同压缩应变速率下的热塑性行为。结果表明:随着应变速率的增加,球墨铸铁在950℃下的极限压下量呈递减趋势。流变曲线随着真应变的增加,迅速达到一峰值后发生软化,即存在动态再结晶行为。利用光学显微镜观察了微观石墨球在明/暗场中的形貌,发现石墨颗粒在三向不等压应力作用下具有一定的塑性,但是应变速率对石墨颗粒的形貌及分布的直接影响并不明显。Hot deformation behavior of QT450-10 spheroidal graphite cast iron（SGCI） was investigated with various high strain rates at 950 ℃ by compression deformation tests on a Gleeble-1500 simulator.The results show that the critical strain decreases gradually while the true stress increases with increasing strain rate and dynamic recrystallization occurs in deformed samples at 950℃.The morphology of graphite particles are observed under light field and dark field via optical microscope.It is found that graphite particles are plastic under quasi-hydrostatic stree and no significant effect of strain rate on the plasticity of graphite particles is observed for QT450-10 SGCI deformed at 950℃.

关 键 词：球墨铸铁 热塑性 应变速率 Gleeble-1500 

分 类 号：TG143.5[一般工业技术—材料科学与工程]