Laser ultrasonics as an innovative sensor for microstructure control

激光超声冶金(Lumet)是加拿大一项新兴的传感器技术，它是一种非接触和无损的技术，用于快速、精确地原位测量微观结构-赋予金属或合金独特性质的“指纹”。我们很幸运地通过成功的CFI申请(大约109万美元)获得了世界上第一个Lumet系统，作为我们的Gleeble 3500热机械模拟器的附件。这是Lumet首次用于专门从事冶金研究的实验室，而不是用于激光开发实验室。激光超声学是利用激光产生和检测超声波的技术。目前，标准金相学--研究金属的微观结构--使用缓慢且劳动密集型的技术。Lumet提供了通过加速实验室研究来改变金属和合金加工性质的潜力，并在目前通过温度测量间接控制微结构的工业线中作为微结构控制的智能传感器。这种潜在的范式转变将推动具有非常理想性能的微结构的设计--这些微结构需要生产创新的材料和产品，使加拿大走在世界冶金工业的前列。在拟议的项目中，激光超声将进一步发展，用于监测钢、铝、钛和镁合金的晶粒长大、再结晶、析出和相变。三名研究生将接受专门的激光超声研究培训，从而将他们定位为加拿大冶金行业这种创新传感器技术的领军者。长期目标是(I)在不列颠哥伦比亚省大学建立一个冶金激光超声波国际英才中心，(Ii)推广Lumet技术，使其成为冶金业界原位微结构表征和控制的新标准。

Laser ultrasonics for metallurgy (LUMet) is an emerging Canadian sensor technology that is a noncontact and nondestructive technique for fast and precise in-situ measurements of microstructures - the "fingerprints" that give a metal or alloy its unique properties. We are fortunate to have acquired the world's first LUMet system as an attachment to our Gleeble 3500 thermo-mechanical simulator through a successful CFI application (of approximately 1.09 million dollar). This is the first time that LUMet will be used in a laboratory dedicated to metallurgical studies rather than in a laser development laboratory. Laser ultrasonics is the generation and detection of ultrasound using lasers. Currently, standard metallography - the study of the microscopic structure of metals - uses slow and labour-intensive techniques. LUMet offers the potential to transform the nature of metal and alloy processing by accelerating laboratory studies and as an intelligent sensor for microstructure control in an industrial line where currently microstructure is indirectly controlled by temperature measurements. This potential paradigm shift will drive the design of microstructures with highly desirable properties - those needed to produce the innovative materials and products that will put Canada at the forefront of the metallurgical industry worldwide. In the proposed project laser ultrasonics will be further advanced for monitoring grain growth, recrystallization, precipitation and phase transformations in steels, Al, Ti and Mg alloys. Three graduate students will be trained with dedicated laser ultrasonic studies thereby positioning them as champions of this innovative sensor technology in Canada's metallurgical industry. The long term objectives are (i) to establish an international Centre of Excellence on laser ultrasonics for metallurgy at the University of British Columbia and (ii) to promote the LUMet technology as a new standard for in-situ microstructure characterization and control in the metallurgical community.