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。

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.