Thermomechanical aspect and high-strain rate behavior of next generation advanced high-strength materials

加拿大政府和汽车行业定期审查政策、标准和法规，以确保司机和乘客的安全，并实现到2030年从目前的704百万吨二氧化碳当量增加到5.17亿吨二氧化碳当量的年度温室气体排放目标。拟议的冶金研究计划旨在通过提高汽车的燃料效率来减少加拿大的温室气体排放，同时加强加拿大经济，通过开发新型、轻质、清洁和经济的第三代先进高强度钢(AHSS)，采用非传统合金化概念，锰含量为8-10wt%。钢并不是一种过时的材料。尽管汽车零部件的其他金属轻质材料也在发展，但在可预见的未来，白色车身的重要部件仍然是钢制的，而且永远是钢制的。这是因为它集经济性、强度和耐用性于一身。事实上，世界各地的钢铁行业都在积极地继续开发下一代AHSS。该项目将分为四个主要阶段。第一阶段致力于新型AHSS的合金设计、层错能(SFE)分析、热力学评估和铸造。这些中锰钢的设计将达到超过1000兆帕的抗拉强度和30-40%的伸长率。第二阶段包括这些钢的热处理和冷却循环，以建立平衡相变、冷却曲线和相图。第三阶段包括实验室规模的热机械加工模拟，如热轧和热锻造，以评估这些材料的成形性。耐撞性将通过进行高速变形实验进行评估。第四阶段和最后阶段包括广泛的组织特征，以准确地了解孪生诱发塑性(TWIP)、相变诱导塑性(TRIP)和沉淀硬化对中锰钢力学性能的单独影响。在项目结束时，将开发四个新的第三代AHSS，并建立明确的工艺-组织-性能关系。这些材料的商业性也将得到评估。这项工作的成果有望加速设计和发现新的、高性能和节能的材料。10名高素质人才(HQP)，其中包括5名研究生(2名博士和3名MSCE)和5名本科生，预计将加入并加强加拿大的汽车和制造业。预计他们将支持研究和开发活动，并保持加拿大工业的竞争力。

The Canadian government and automotive industries regularly review the policies, standards and regulations to ensure the safety of both drivers and passengers, as well as to meet the annual greenhouse emission target from the present 704 megatonnes to 517 megatonnes of carbon dioxide equivalent by the year 2030. The proposed metallurgical research program is aimed to reduce the greenhouse emission of Canada by improving the fuel efficiency of automotive vehicles while strengthening the Canadian economy, through the development of a novel, lightweight, clean and economic third generation advanced high-strength steels (AHSS) using unconventional alloying concepts with manganese content of 8-10 wt%. Steel is not an obsolete material. Despite the development of other metallic lightweight materials for automotive parts, significant parts of the body-in-white are still and will always be made of steel in the foreseeable future. This is because of its exceptional combination of economy, strength and durability. In fact, steel industries around the world are aggressively continuing to develop the next generation AHSS. This project will be divided into four major phases. The first phase is dedicated to alloy design, stacking-fault energy (SFE) analysis, thermodynamic assessment, and casting of novel AHSS. These medium-manganese steels will be designed to achieve tensile strengths of more than 1000 MPa with elongations of 30-40%. The second phase involves heat treatment and cooling cycles of these steels to establish the equilibrium phase transitions, cooling curves and phase diagrams. The third phase involves laboratory-scale simulation of thermomechanical processing such as hot rolling and hot forging to assess the formability of these materials. The crashworthiness will be evaluated by performing high-speed deformation experiments. The fourth and final phase covers extensive microstructural characterization to accurately understand the individual effects of twinning-induced plasticity (TWIP), transformation-induced plasticity (TRIP) and precipitation hardening on the mechanical properties of medium manganese steels. At the end of the project, four new third generation AHSS will be developed and a clear processing-microstructure-property relationship will be established. The commerciality of these materials will also be evaluated. The results from this work are expected to accelerate the design and discovery of new, high-performance and energy-saving materials. Ten highly qualified personnel (HQP), which consist of five graduate (two PhDs and three MScEs) and five undergraduate students are expected to join and strengthen the Canadian automotive and manufacturing industries. They are expected to support the research and development activities and maintain the competitiveness of Canadian industries.