线性和非线性扭曲挤出过程与晶体可塑性的比较 有限元素分析
Ülke Şimşek1,2, Kemal Davut3, Hiroyuki Miyamoto4
1Roketsan Missiles Industries Inc., Ankara 06780, Türkiye.
Materials (Basel, Switzerland)
|March 13, 2024
概括
严重的塑性变形 (SPD) 提炼了颗粒大小,增强了金属的强度. 一种新的非线性扭曲挤出 (NLTE) 方法通过优化铜的微观结构和纹理演变来改进线性扭曲挤出 (LTE).
科学领域:
- 材料科学与工程 材料科学与工程
- 金工业是金工业的一个方面.
- 计算材料科学科学 计算材料科学
背景情况:
- 颗粒大小是一个关键的微观结构参数,影响多晶金属的强度和性等机械性能.
- 严重的塑性变形 (SPD) 技术用于实现超细粒度 (UFG) 微结构,增强材料性能.
- 在SPD过程中纹理演变显著影响塑料的行为和可塑性,使其预测对流程优化至关重要.
研究的目的:
- 分析和比较线性扭转挤出 (LTE) 和一种新的非线性扭转挤出 (NLTE) 工艺的性能.
- 为了研究LTE和NLTE的单晶铜的纹理演变和应力和应变的分布.
- 评估NLTE在缓解传统扭曲挤出方法缺陷方面的有效性.
主要方法:
- 在模拟中使用了取决于速率的晶体可塑性有限元素 (CPFE) 框架.
- 模拟了单晶铜片通过LTE和NLTE过程的传递.
- 分析样本的初始晶体学方向<100>或<111>与挤出方向平行.
主要成果:
- 对LTE和NLTE都观察到详细的纹理演变模式.
- 压力和应变的横截面分布被绘制出来,揭示了两个过程之间的差异.
- 在解决LTE固有的变压逆转和工件旋转问题方面,NLTE展示了潜在的潜力.
结论:
- 该研究提供了LTE和NLTE用于生产铜UFG微结构的比较分析.
- 在不同的挤出条件下,CPFE模拟为纹理发展和机械反应提供了宝贵的见解.
- 这些发现支持NLTE技术的进一步发展和潜在的工业应用,用于增强材料加工.
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