吕海青,杨善武,张瑞,孙超,贺信莱

• 1:北京科技大学材料科学与工程学院

摘要(Abstract)：

采用冷弯实验、等温热处理结合硬度测量、光学金相技术和透射电子显微术观测分析了微合金钢中贝氏体组织在A1以下温度受热时的组织演化历程。结果表明,提高微合金钢的碳铌浓度积可以显著延缓贝氏体组织趋于平衡的演变,阻碍钢的软化进程。冷变形在增加钢的初始硬度的同时也加快了随后的受热过程中钢的软化和显微组织向平衡组织演化的进程。张应变和压应变这两种不同类型的应变对组织演变的促进效果几乎相同。冷变形提高了钢中位错密度,也加剧了位错分布的不均匀性,后者是预应变加速组织演变的直接原因。在等温受热过程中贝氏体组织的演变首先是贝氏体板条内的位错发生重新分布,在板条边界附近形成高位错密度区,并同时伴随有低位错密度区出现,然后低位错密度区跨越板条边界形成铁素体晶核并不断吞噬高位错密度区,最终完全演变为平衡组织多边形铁素体。

关键词(KeyWords)： 碳铌浓度积;冷变形;微合金钢;贝氏体;热稳定性

Abstract:

Keywords:

基金项目(Foundation): 国家自然科学基金资助项目(50671016)

作者(Author): 吕海青,杨善武,张瑞,孙超,贺信莱

DOI: 10.13289/j.issn.1009-6264.2010.03.028

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