头发如何使钢铁变形
Gianluca Roscioli1, Seyedeh Mohadeseh Taheri-Mousavi1,2, Cemal Cem Tasan3
1Department of Materials Science and Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA.
概括
由于复杂的相互作用,硬化钢在切割软材料时会失效. 马氏体结构的空间变化会导致混合模式的裂纹,导致工具在显著磨损之前出现故障.
科学领域:
- 材料科学
- 部落学
- 金属工程
背景情况:
- 具有马氏体微结构,高碳化物含量和涂层的钢是为了硬度和耐磨性而设计的.
- 这些工具钢在切割比较柔软的材料如头发,奶酪或土豆时会失效,这是缺乏机械学理解的日常观察.
- 材料和变形条件之间的复杂相互作用阻碍了对故障微机理的理解.
研究的目的:
- 阐明硬钢在切割软材料时出现故障的微观机制.
- 研究马氏体微观结构在观察到的材料故障中的作用.
- 了解工具钢从切割到磨损的过程.
主要方法:
- 使用专门的微机械测试设置进行中断切割测试.
- 使用现场电子显微镜观察微观尺度上的变形和断裂过程.
- 为了补充实验发现,进行了分析和数值调查.
主要成果:
- 马氏体结构中的空间变化被确定为材料故障的关键因素.
- 观察到一种混合模式的II-III裂变现象.
- 这种破裂发生在显著的材料磨损开始之前,解释了过早的故障.
结论:
- 拉斯马石的微结构异质性是削减软材料的工具钢过早失效的主要原因.
- 了解这种混合模式破裂机制对于设计更强大的切削工具至关重要.
- 进一步研究微观结构与属性的关系可以提高工具的性能和寿命.
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