空洞缺陷对Ni/Ni3Al晶体内行为的影响
Longlong Yang1, Kun Sun1, Huaying Wu2
1State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an 710049, China.
Nanomaterials (Basel, Switzerland)
|July 14, 2023
概括
超级合金Inconel 718中的空隙对机械性能产生重大影响. 更大的空隙半径和更高的基板温度降低了硬度和Young.
科学领域:
- 材料科学 材料科学 材料科学
- 机械工程 机械工程
- 计算材料科学科学 计算材料科学
背景情况:
- 英康尼尔718 (IN 718) 超合金是以其卓越的机械性能而闻名的关键工程材料.
- 空隙是IN 718超合金制造中的固有缺陷,对机械性能产生负面影响.
研究的目的:
- 系统地研究空隙特性和基板温度对Ni/Ni3Al晶体机械性能的影响.
- 了解空隙参数如何影响基于Ni的超级合金中的脱位形成和机械反应.
主要方法:
- 用分子动力学 (MD) 模拟来建模Ni/Ni3Al晶体结构.
- 进行了空隙半径,空隙至表面距离和基板温度的系统变化.
- 分析的重点是楼梯杆和Shockley脱位的形成及其与机械性质的相关性.
主要成果:
- 空隙半径的增加导致模和硬度的下降.
- 从空隙到基板表面的距离增加,在稳定之前,最初增加了机械性能.
- 升高的基质温度导致不规则的相间界限和增加的缺陷,降低了模和硬度.
结论:
- 空隙几何和基板温度是影响IN 718超级合金机械行为的关键因素.
- 这项研究提供了关于在空隙存在时控制机械性能的脱位机制的见解.
- 这些发现为优化IN 718超级合金制备和通过MD模拟预测痕特性提供了指导.
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