Investigation of the Micro-Mechanical Phenomena Operative during Elevated Temperature Forming and in the As-Received (and As-Formed) Condition of Novel Automotive Light Weighting Metals

越来越严格的燃油经济性和排放标准促使汽车行业提高车辆效率，努力达到奥巴马政府规定的企业平均燃油经济性（CAFE）目标，即到2025年达到54.5英里/加仑。这刺激了最近高强度铝和（iii）第三代传统冲压的显著增加，这是Discovery研究计划的重点，该计划将研究高温成形和室温变形对这些材料微观力学行为的影响。拟议研究的目标将解决：****(1)相变的影响；三轴性和高温变形对铝合金热成形微观力学行为的影响***(2)多相相互作用和轻量化金属损伤演化的影响****(3)建立具有代表性的体积元（RVE）有限元模型，模拟轻量化金属的实测本构和断裂行为***将在纳米分辨率场发射下进行最先进的原位力学测试扫描电镜（FE-SEM）研究(i)多相显微组织（ii）温度（iii）应力状态（三轴性）（iv）应变速率和(v)相变对这些材料微观力学行为的影响。实验结果将导致RVE有限元模型的发展，以模拟这些轻量化加工金属的本构和断裂行为。表征结果和RVE模型将被行业（材料生产商、零部件制造商、汽车制造商）采用，以改进先进制造工艺，提高轻量化零部件的使用性能。从长远来看，汽车轻量化将通过减少排放有利于我们的健康和环境，轻量化技术的进步也将通过确保加拿大作为先进制造商的实力而有利于我们的经济。*****

Increasingly stringent fuel economy and emissions standards have driven the automotive industry to improve vehicle efficiency in an effort to meet the corporate average fuel economy (CAFE) target of 54.5 mpg (by 2025) as mandated by the Obama administration. This has spurred a recent and significant increase in Rof high strength aluminum and (iii) conventional stamping of 3rd Generation Qare the focus of the proposed Discovery research program, which will investigate the effect of elevated temperature forming and room temperature deformation on the micro-mechanical behaviour of these materials. The objectives of the proposed research will address:****(1) The effect of phase transformations, triaxiality and elevated temperature deformation on the micro-mechanical behaviour of aluminum alloys during warm forming***(2) The effect of multi-phase interaction and damage evolution of light weighting metals****(3) The development of representative volume element (RVE) finite element models to simulate the measured constitutive and fracture behaviour of the light weighting metals***State-of-the-art in-situ mechanical testing will be conducted within a nanometer resolution field emission scanning electron microscope (FE-SEM) to investigate the effect of (i) multi-phase microstructures (ii) temperature (iii) stress-state (triaxiality) (iv) strain rate and (v) phase-transformations on the micro-mechanical behavior of these materials. The experimental results will then lead to the development of RVE finite element models to simulate the constitutive and fracture behavior of these light weighting processes metals. The characterization results and RVE models will be adopted by industry (material producers, parts manufacturers, car makers) to improve the advanced manufacturing processes and enhanced the in-service performance of light weighted parts. Long term, vehicle light weighting will benefit our health and the environment through reduced emissions and the advancement of light weighting technologies will also benefit our economy, by securing Canada's strength as advanced manufacturers.*****