Optimization of mechanically induced phase transformation at crack tip in metal for improved crack growth resistance

在过去的几十年里，在开发先进材料和制造工艺方面取得了实质性进展，以增加承载能力并促进金属部件的维护。高抗疲劳钢和电子束焊接的发展是能源生产和汽车工业中使用的技术突破的例子。虽然这些技术很有前景，但由于缺乏基础知识和实验数据，无法准确预测尺寸和使用寿命，因此它们在制造和修复疲劳关键部件方面的应用仍然有限。为了释放创新材料和工艺的全部潜力，至关重要的是，在部件疲劳行为的表征和基本理解方面取得重大进展，以及相关的损伤机制。提出的DGP的总体和长期目标是对循环载荷下的相变诱发塑性（TRIP）有一个基本的理解，这是开发和制造具有改进的抗裂纹扩展能力的新材料所必需的。这些新材料的成果与汽车、航空航天和能源生产部门有关。该计划的具体目标是：1)了解和控制奥氏体的力学稳定性（TRIP动力学）；2)了解和表征TRIP辅助显微组织中的裂纹扩展动力学。DGP项目的独特性将转化为先进疲劳测试、新材料和工艺开发以及关键部件耐久性方面的重大科学贡献，这将引起业界的极大兴趣。它将支持来自魁北克工业（Sodel, Velan, Hydro-Quebec）的创新材料和工艺的开发和接受，并强调组件的耐用性。它还将有助于采用将对能源生产产生积极影响的技术，因为这些技术可以改善部件的承载能力，并通过减少灾难性故障的可能性对环境产生积极影响。Brochu教授的多学科学术背景，加上作为专业工程师的10年工业实践，丰富了她的学术工作，并使她成为金属材料疲劳领域的国际公认的领导者。自2011年以来，被提名人已为59名高素质人才（HQP）的培训做出了贡献。8名hqp将在这项发现资助的研究项目中接受培训。

Over the past decades, substantial progress has been made on the development of advanced materials and manufacturing processes to increase load bearing capacity and to facilitate the maintenance of metallic components. Development of high fatigue resistant steels and electron beam welding are examples of technological breakthroughs used in the energy production and automotive industries. While these technologies are promising, their utilization to manufacture and repair fatigue critical components remains limited due to the lack of fundamental knowledge and experimental data that prevent accurate sizing and service life prediction. To unleash the full potential of innovative materials and processes, it is crucial that significant progress be made on the characterization and fundamental understanding of component's fatigue behavior, and the related damage mechanisms. The overarching and long-term goal of the proposed DGP is to develop a fundamental understanding of the transformation induced plasticity (TRIP) under cyclic loading required to the development and manufacture of novel materials with an improved resistance to crack propagation. Outcomes for these new materials are pertinent for the automotive, the aerospace and the energy production sectors. The specific objectives (SO) of the program are SO1) to understand and control the mechanical stability of austenite (TRIP kinetic) and SO2) to understand and characterize the crack growth kinetic in the TRIP-aided microstructures. The uniqueness of the DGP program will translate into major scientific contributions on advanced fatigue testing, on the development of new materials and processes and on the durability of critical component that will be of great interest to the industry. It will support the development and acceptance of innovative materials and processes stemming from Quebec industries (Sodel, Velan, Hydro-Quebec) with a strong emphasis on components durability. It will also contribute to the adoption of technologies that will have a positive impact on energy production, by improving the load bearing capacity of components, and on the environment, by reducing the probability of catastrophic failures. Prof. Brochu's multidisciplinary academic background combined with a 10-year period of industrial practice as a professional engineer have enriched her academic work and contributed to her international recognition as a leader in the field of fatigue of metallic materials. Since 2011, the nominee has contributed to the training of 59 highly qualified persons (HQP)s. Eight HQPs will be trained within the research program of this discovery grant.