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，在其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。这导致了一个重大的挑战，即通过预测建模来开发“设计型微结构”，并对这种材料进行加工，以提供完全可预测的性能。这只能通过对材料开发和材料加工以及对微观结构和织构发展的影响的综合、多学科的方法来实现。要实现这一点，需要阐明和量化工艺变量，这些变量对变形诱导的显微组织以及随后通过工艺路线发生的相变和再结晶事件具有重大影响。只有实现了这一点，才会有足够的科学基础来开发基于物理的直通工艺模型，以预测目标组织和织构的理想工艺路线。其目标是为实验室实验和基于工业的试验提供信息，以引导减少周期，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(IMMPETUS)微观结构和机械工程研究所(IMMPETUS)的专业知识和世界级热加工模拟设施，以及瑞典机械冶金、腐蚀和金属研究所机械冶金、腐蚀和金属研究所系主任Bevis Hutchinson教授对IMMPETUS进行为期六个月的访问，针对热机械加工过程中微观组织演变建模的一些关键方面。哈钦森教授是世界著名的热加工钢和冷加工钢的显微组织和织构演化领域的专家。他的访问为英国研究人员和实业家，特别是与IMMPETUS计划相关的许多人提供了一个独特的机会，以获得有关众多因素的第一手知识，这些因素据信有助于通过热机械加工路线产生钢的微观结构和织构。哈钦森教授此行的主要主题将是：对拟议的钢铁相变和变种选择机制提供进一步的独立证据。近年来，这一领域的研究受到了极大的关注。然而，对已提出的许多理论进行研究的独立工作有限。事实上，由于缺少信息，例如奥氏体中的起始织构，这些理论不能完全得到验证。然而，IMMPETUS最近开发的一种模型奥氏体合金将首次允许获得这种缺失的信息。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，从而澄清关键的过程变量，从而制定出明确的建模策略。此外，Hutchinson教授的访问将补充IMMPETUS正在进行的广泛工作，并将一些新概念引入IMMPETUS框架，特别是晶体织构进化。

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.