在硬化金属中使用扩展性剪切带
1The CAST CRC, Materials Engineering, The University of Queensland, Brisbane, Queensland 4072, Australia. c.gourlay@minmet.uq.edu.au
Nature
|January 5, 2007
概括
部分固化的合金表现得像颗粒材料一样,表现出扩张性和应变局部化. 这种颗粒状的行为对于理解和合金高压压造中的缺陷至关重要.
科学领域:
- 材料科学 材料科学 材料科学
- 物理 物理学 物理
- 工程 工程师 工程师 工程师
背景情况:
- 压缩颗粒材料在剪切下表现出独特的行为,与其构成阶段不同.
- 颗粒物理原理在土壤力学和雪崩等领域的理解有所提高.
- 金属合金固化包括在某些固体部分拥挤的液晶晶体微结构.
研究的目的:
- 为了研究是否部分固化的金属合金变形为颗粒状材料.
- 探索颗粒物材料行为与固化加工的相关性.
- 了解合金造中的缺陷形成机制.
主要方法:
- 对部分固化的合金进行实验观察.
- 在剪切下微观结构变形的分析.
- 与已确定的颗粒力学原理进行比较,例如扩张性和应变局部化.
主要成果:
- 部分凝固合金表现出无凝聚性颗粒材料的特征.
- 在剪切带中观察到雷诺兹的扩张和应变局部化.
- 这种颗粒状的行为直接影响Al和Mg合金的高压压中缺陷的形成.
结论:
- 颗粒力学原理可以应用于固化加工.
- 了解合金中的颗粒状行为为减少缺陷提供了洞察力.
- 颗粒力学和固化科学之间的协同作用具有重要的创新潜力.
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