报告题目：Ultrasonic spot welding of multi-materials for structural applications
主 讲 人：陈道伦
The transportation industry is facing increasing pressures in several key areas including energy, emissions, and safety. Lightweighting is one of the most effective strategies to address these challenges, since a 10% weight reduction results in a 6~8% fuel-efficiency gain. It has recently been portrayed as the “storm” of lightweighting – a revolution in materials, processes, and business models – which is brewing on the horizon of the automotive industry. Vehicle lightweighting can be better achieved via a “multi-material” concept, where the characteristics of different materials (e.g., advanced high-strength steels, aluminum, magnesium alloys) are optimized for the desired applications for lightweighting, cost effectiveness and value addition. The structural applications of such multi-materials inevitably involve welding and joining, particularly dissimilar welding. This poses significant challenges due to different thermophysical and mechanical properties and the related safety and durability issues of welded joints. In this talk several examples on the welding of similar (Mg/Mg, Al/Al, steel/steel) and dissimilar (Mg/Al, Mg/steel, Al/steel) will be presented. The weld interface experienced dynamic recrystallization during similar welding, while an intermetallic compound layer or a eutectic layer was formed during dissimilar welding, depending on the material combinations. To minimize the occurrence of intermetallic compounds, a zinc or tin interlayer was also used during dissimilar welding, leading to the improved tensile lap shear strength of the dissimilar welded joints. The evolution in the microstructure and texture as well as fatigue properties and fracture mechanisms of the welded joints will be presented.
陈道伦，加拿大工程院院士(FCAE)，加拿大矿业，冶金和石油协会会士(FCIM)，英国材料，矿物和采矿协会会士(FIMMM)，加拿大多伦多瑞尔森大学机械和工业工程系教授。1983年和1986年分别获东北大学工学学士和硕士学位，1989年获中国科学院金属研究所博士学位，1993年获得奥地利维也纳大学博士学位。陈博士在先进材料和关键工程材料的变形、疲劳、焊接等领域发表了385篇同行评审论文，撰写了193篇非同行评审会议论文和研究报告。他在纳米复合材料方面取得突破性成就，其中一种强度计算方法是以他的名字命名的，并且相关论文两次被加拿大科学院理事会确定为“Top1%高被引论文”。陈博士是安大略省长卓越研究奖、MetSoc卓越研究奖、MetSoc杰出科学家奖、Sarwan Sahota杰出学者奖、加拿大金属物理奖和加拿大机械工程学会G.H. Duggan勋章的获得者, 是《Materials Research Letters》、《Materials and Design》、《Materials Science and Engineering A》等30种国际期刊的副主编或编委会成员, 并受邀对发表在《Nature》 和《Science》杂志上的一些重大科学问题进行评论。