温度对接高Mn钢的变形机制和机械性能的影响,用于冷应用
Minha Park1, Gang Ho Lee1,2, Geon-Woo Park1
1Energy System Group, Korea Institute of Industrial Technology, Busan 46938, Republic of Korea.
Materials (Basel, Switzerland)
|August 29, 2024
概括
接后的热处理使高钢微结构均化,防止在冷变形过程中发生不必要的马氏体变化. 这提高了材料稳定性,适用于要求高低温的应用.
科学领域:
- 材料科学 材料科学 材料科学
- 金工业是金工业的一个方面.
- 低温工程 低温工程是什么?
背景情况:
- 高 (高Mn) 钢具有出色的冷性能,对于低温应用至关重要.
- 在冷温度下的变形行为由堆叠故障能量 (SFE) 控制,影响相位转换 (ε-马氏体,α'-马氏体).
- 高Mn钢的潜弧接 (SAW) 可以导致微观结构不均质和残余应力.
研究的目的:
- 研究接后热处理 (PWHT) 对接高Mn钢的微观结构和冷变形行为的影响.
- 分析PWHT对分布和SFE的影响.
- 在低温条件下评估接和热处理的高Mn钢的马氏体变化.
主要方法:
- 使用潜弧接 (SAW) 制造厚厚的高Mn钢管.
- 应用接后热处理 (PWHT) 来均化微结构并减少残余应力.
- 堆叠故障能量 (SFE) 的计算和在冷温度下检查变形行为.
主要成果:
- PWHT减少了树突和树突间区域之间的分离,从而导致更均的微观结构.
- 在冷温度下,SFE下降到20mJ/m2以下,表明了马氏体转化区域.
- 作为接的标本显示在低温温度下拉伸变形时的ε和α'-马丁石变形,而热处理的标本没有.
结论:
- PWHT有效地使高Mn钢微结构均化,改善了冷应用的性能.
- 在低温温度下,热处理可以抑制不良的α'-马丁石的形成.
- 该研究为控制高Mn钢的相变态行为提供了关键的见解,以在极端环境中提高性能.
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