Investigating deformation microstructure evolution and transformation behaviour of steel using controlled thermomechanical compression

超过95%的冶金产品，无论是传统的还是新型的，在生产过程中都要经历一个或多个热机械过程。这类产品的市场竞争非常激烈。成功需要最好的质量、一致性和特性。这导致了通过预测建模开发“设计微结构”的重大挑战，并对这些材料进行处理，使其具有完全可预测的特性。这只能通过综合的、多学科的方法来实现材料开发和材料加工以及对微观结构和织构发展的影响。为了实现这一点，需要阐明和量化对变形引起的微观结构以及随后在工艺路线中发生的转变和再结晶事件有重大影响的加工变量。只有实现了这一点，才会有足够的科学基础来发展基于物理的、贯穿过程的模型，以预测目标微观结构和纹理的理想工艺路线。目标是为实验室实验和工业试验提供信息，以减少周期，提高生产率和增强材料性能。该项目旨在通过结合谢菲尔德大学微观结构和机械工程研究所（IMMPETUS）的专业知识和世界一流的热加工模拟设施，以及Bevis Hutchinson教授（瑞典腐蚀和金属研究所机械冶金系主任）对IMMPETUS进行为期六个月的访问，针对热机械加工过程中微观结构演变建模的一些关键方面。哈钦森教授是冷热加工钢微观结构和织构演变领域的世界知名专家。他的访问为英国研究人员和实业家提供了一个独特的机会，特别是与IMMPETUS计划有关的许多人，可以获得第一手的知识，这些知识被认为有助于通过热机械加工路线产生钢的微观结构和纹理。哈钦森教授访问的主题将是：进一步独立的证据提出的机制相变和变体选择钢。近年来，这一研究领域受到了极大的关注。然而，只有有限的独立工作来调查已经提出的许多理论。事实上，由于缺少信息，如奥氏体的起始织构，这些理论不能被完全验证。然而，impetus最近开发的一种模型奥氏体合金将首次允许推导出这些缺失的信息。通过使用IMMPETUS最先进的热机械压缩模拟器，我们将在受控条件下验证或反驳理论，从而澄清关键过程变量，从而制定明确的建模策略。此外，Hutchinson教授的访问将补充IMMPETUS中正在进行的广泛工作，并将一些新概念引入IMMPETUS框架，特别是晶体织构演化。

Over 95% of metallurgical products, both traditional and novel, undergo one or more thermomechanical processes in their production. The market place for such products is extremely competitive. Success requires the very best in quality, consistency and properties. This has led to a major challenge to develop 'designer microstructures' through predictive modelling and to process such materials to give entirely predictable properties. This can only be achieved through an integrated, multidisciplinary approach to materials development and materials processing and the effect on microstructure and texture development. To make this a reality requires elucidation and quantification of the processing variables that have a significant influence on the deformation induced microstructure and subsequent transformation and recrystallisation events that occur through the process route. Only when this has been achieved will there be sufficient scientific underpinning for the development of physically-based, through-process models to predict the ideal process route for a targeted microstructure and texture. The goal is to inform laboratory experiment and industrially based trials leading reduction cycle, improved productivity and enhanced material properties. This project aims to target some critical aspects of the modelling of microstructural evolution during thermomechanical processing by combining the expertise and world class hot working simulation facilities of the Institute for Microstructural and Mechanical Engineering: The University of Sheffield (IMMPETUS) with a six month visit to IMMPETUS by Professor Bevis Hutchinson (Head of Department of Mechanical Metallurgy, Corrosion and Metals Research Institute, Sweden). Prof Hutchinson is a renowned world expert in the fields of microstructure and texture evolution in hot and cold worked steels. His visit represents a unique opportunity for UK researchers and industrialists, particularly the many associated with the IMMPETUS programme, to gain first hand knowledge of the numerous factors that are believed to contribute to the generation of microstructure and texture in steels through the thermomechanical processing route. The main theme of Prof Hutchinson's visit will be: Further independent evidence of the proposed mechanisms for phase transformation and variant selection in steels. This area of research has received significant attention over recent years. However, there is only limited independent work investigating the many theories that have been proposed. Indeed, the theories cannot be fully validated because of the missing information, such as the starting texture in the austenite. However, a recently developed model austenitic alloy, developed by IMMPETUS, will allow, for the first time, this missing information to be derived. By using IMMPETUS' state-of-the-art thermomechanical compression simulator, we will validate or disprove the theories under controlled conditions and thereby clarify the critical process variables such that a clear modelling strategy can be developed. In addition, the visit of Prof Hutchinson will complement a wide range of work that is being done in IMMPETUS as well as introducing a number of new concepts into the IMMPETUS framework, in particular crystallographic texture evolution.