崔文芳,张思勋,任海鹏,刘春明

• 1:东北大学材料各向异性与织构教育部重点实验室
• 2:莱芜钢铁股份有限公司技术中心

摘要(Abstract)：

为考察新型超低碳贝氏体钢连铸坯的热塑性,利用热模拟实验技术研究了Cu-P合金化超低碳贝氏体钢在750～1350℃温度范围的拉伸应力-应变行为,热塑性和拉伸断口的变化,分析了产生这些变化的原因和磷对热塑性的影响机理。结果表明:Cu-P合金化使超低碳贝氏体钢高温拉伸时发生颈缩的应变量减小,但在750～1300℃温区的断面收缩率均达到60%以上。钢中微量硼有效抑制磷在奥氏体晶界的偏聚以及降低先共析铁素体的相变温度是高磷钢保持良好热塑性的主要原因。在800～900℃热塑性的下降与形变诱发Nb(C,N)粒子析出有关。根据热塑性和抗拉强度的变化规律,建议连铸坯在一冷区采取强冷,使表面温度迅速降低到1350℃以下,在二冷区采取弱冷,温度保持在800℃以上,从而使连铸坯始终具有较高的热塑性。

关键词(KeyWords)： 低合金钢;贝氏体;热塑性;晶界偏聚;断口

Abstract:

Keywords:

基金项目(Foundation): 长江学者与创新团队发展计划资助(IRT0713)

作者(Author): 崔文芳,张思勋,任海鹏,刘春明

DOI: 10.13289/j.issn.1009-6264.2011.09.015

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