兰鹏,李阳,张家泉

• 1:北京科技大学钢铁冶金新技术国家重点实验室
• 2:北京科技大学冶金与生态工程学院

摘要(Abstract)：

实验分析了灰口铸铁经周期性的高温氧化处理后,其抗拉强度、基体组织、断口形貌与化学成分的变化规律,并探讨了热疲劳载荷下灰口铸铁失效的微观-宏观机制。结果表明:灰口铸铁的抗拉强度和抗热疲劳性能在微观上与石墨形貌、基体组织和晶粒尺寸有关,宏观上受温度、氧化条件、载荷周期和化学成分的影响。随着高温氧化处理次数增加,试样脱碳越来越明显,珠光体逐步减少直至消失;同时,短小而零碎的新石墨不断形成,断口处石墨暴露率逐步增大,基体连续性显著恶化;此外,试样基体铁素体化后,尽管脱碳速率降低,但基体晶粒逐步粗化、二次渗碳体析出使晶界弱化,各温度下抗拉强度随碳含量减小而显著下降。

关键词(KeyWords)： 铸铁;热疲劳;微观组织;拉伸性能

Abstract:

Keywords:

基金项目(Foundation):

作者(Author): 兰鹏,李阳,张家泉

DOI: 10.13289/j.issn.1009-6264.2014.04.028

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