Simulating nucleation and short crack propagation using cellular automaton in gradient microstructures

使用元胞自动机模拟梯度微结构中的成核和短裂纹扩展

• 批准号: RGPIN-2018-05291
• 负责人: Bocher, Philippe
• 金额: $ 3.35万
• 依托单位: École de technologie supérieure
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=754407
• 关键词: Simulating; nucleation; short; crack; propagation

The proposed research is a continuation of previous discovery grants dedicated to the development of Cellular Automata (CA) methods applied to micromechanics. Thanks to this support, CA have been used to simulate cold creep / fatigue interactions in titanium alloys and localise stress distributions at the microstructural scale in polycrystals. In the present proposal, CA will be further develop to investigate crack initiation and propagation in material including microstructure gradients. This will help developing statistical based models for the fatigue life prediction of surface treated parts. CA, which are fully discrete, spatial-distributed, dynamical systems, serve as an alternative framework for mathematical descriptions and analysis of physical systems. Despite providing computational advantages, CA have not been extensively used in the framework of material science and mechanical engineering and the present candidate is a leader in this domain. The principal and long-term objective of the proposal is to developed CA models able to calculate the crack initiation and propagation from the stress and strain heterogeneities induced by surface treatment processes and applied loads, allowing the development of a statistical approach. Secondary objectives include further development of experimental techniques to calibrate and validate the developed models by documenting the adaptation of the microstructures during fatigue tests for various microstructures and alloys. Surface treatment such as machining, surface peening (hammer or shot), carburizing or induction hardening will be investigated as they are some of the surface treatments investigated by the candidate. Experimental validations will also be covered by the present proposal. The scale at which the measurements have required the development of original and precise techniques that are now available for further material investigation. The statistical results gathered by the CA models will be integrated to various microstructural-based model for fatigue life prediction.

拟议的研究是延续以前的发现补助金，该发现致力于开发用于微力学的细胞自动机（CA）方法。由于获得了这种支持，CA已被用于模拟钛合金中的冷蠕变 /疲劳相互作用，并在多晶体中以微结构尺度定位应力分布。在本提案中，将进一步发展CA，以研究包括微观结构梯度在内的材料中的裂纹启动和传播。这将有助于开发基于统计的模型，用于表面处理部分的疲劳寿命预测。 CA是完全离散的，空间分布的动态系统，是数学描述和物理系统分析的替代框架。尽管提供了计算优势，但CA尚未在材料科学和机械工程的框架中广泛使用，而当前的候选人是该领域的领导者。该提案的主要目标和长期目标是开发了CA模型，能够计算出由表面处理过程和施加载荷引起的压力和应变异质性的裂纹引发和传播，从而允许开发统计方法。次要目标包括进一步开发实验技术，以通过记录在各种微观结构和合金的疲劳测试中记录微观结构的适应开发模型。将研究表面处理，例如加工，表面镀皮（锤子或射击），渗碳或诱导硬化，因为它们是候选人研究的一些表面处理。本提案也将涵盖实验验证。测量需要开发原始技术和精确技术的规模，这些技术现在可用于进一步研究。 CA模型收集的统计结果将集成到基于微观结构的各种疲劳寿命预测模型中。