变量定量相场建模非异热烧结过程的变量定量相场建模
Timileyin David Oyedeji1, Yangyiwei Yang1, Herbert Egger2
1Mechanics of Functional Materials Division, Institute of Materials Science, Technische Universität Darmstadt, 64287 Darmstadt, Germany.
Physical review. E
|September 19, 2023
概括
这项研究引入了一种非异热烧结的新变相场模型,克服了人工接口效应,并确保了准确的孔状结构演变建模的热力学有效性.
科学领域:
- 材料科学 材料科学 材料科学
- 计算材料科学科学 计算材料科学
- 热力学是一种热力学.
背景情况:
- 阶段场建模对于模拟烧结至关重要,但面临着定量准确性和人工接口效应的挑战.
- 现有的模型在非同热烧结中的固体孔界面上的不对称质量和热特性方面存在困难.
- 规定的防陷术语可能会损害模型的热力学变化性质.
研究的目的:
- 为非异热烧结工艺开发一个变化和定量相场模型.
- 为了解决人工接口效应并确保热力学有效性.
- 为了准确地捕捉质量/热转移和谷物生长之间的相互作用.
主要方法:
- 开发了一个扩展的非对角相场模型,用于非异热烧结.
- 在保存 (质量,热量) 和非保存 (谷物生长) 动力学之间包含自然交叉合的术语.
- 利用非对称分析来验证界面工件的消除和保证热力学平衡.
- 引入了一种针对动力运动的异构互插方案.
主要成果:
- 开发的模型消除了接口工件,而不会改变热力学平衡.
- 交叉合术语被证明对于精确模拟烧结至关重要.
- 证明了捕捉效应和表面扩散的方向依赖性.
- 动力流动性的异型合对于捕捉热微结构演变至关重要.
结论:
- 新的变异相场模型为非异热烧结提供了一种定量有效的方法.
- 该模型通过解决接口现象,准确地捕捉了复杂的热微结构演变.
- 这项工作促进了相场建模在材料加工中的应用.
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