GOALI/Collaborative Research: Fundamental Research on Impact Welding of Aluminum and Steel

GOALI/合作研究：铝和钢冲击焊接的基础研究

• 批准号: 1537471
• 负责人: Brad Kinsey
• 金额: $ 11.2万
• 依托单位: University of New Hampshire
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-08-01 至 2020-11-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1537471&HistoricalAwards=false
• 关键词: GOALI; Collaborative; Research; Fundamental; Impact

This Grant Opportunity for Academic Liaison with Industry (GOALI) collaborative research award supports fundamental research on an emerging welding technology - impact welding - to join material combinations that are otherwise difficult to join. Research will focus on aluminum-steel welds because there are diverse and important commercial needs in joining these metals. Both base metals are well characterized and the development of robust aluminum-steel unions can reduce automobile mass. Lighter cars use less fuel and emit less carbon to the atmosphere. Research results will enable wider application of this technology in important industries including automotive, aerospace, and medical devices. Traditional welding processes melt both metals to be joined and the molten mixing can result in brittle intermetallic compounds, rendering the joints unsuitable for most structural applications. Impact welds can be strong and tough and are created in the solid state by a high-speed (typically 200-700 m/s) oblique collision between two metal surfaces. The objectives of this research are: 1) to understand how the thickness of the flyer plate (and therefore its total kinetic energy) affects the structure of the interface that is formed, 2) to understand the real-time evolution of strain, temperature and morphology of the interface during the impact welding process and 3) relate the deformation history to the final structure and properties of the weld. Unique tools are used to study aluminum-steel impacts from flyer thicknesses of 25 µm to 25 mm. Laser impact welding and explosive welding are used for the thinnest and thickest flyers, respectively, while vaporizing foil actuator welding will be used to accelerate flyers of several intermediate thicknesses. Photonic Doppler velocimetry will enable detailed measurements of collision speed and angle. Finite element models based on Smoothed Particle Hydrodynamics and Arbitrary Lagrangian-Eulerian methods will be developed for these problems. Their validity will be tested by metallographic examination of welded structures and comparison of these to simulation. These models will be used to understand the complex dynamic development of material strains, temperatures and structures and on a wide range of length scales.

这项学术与工业联络合作研究资助机会（GOALI）支持对新兴焊接技术（冲击焊接）的基础研究，以连接难以连接的材料组合。研究将集中在铝-钢焊接上，因为连接这些金属有多种重要的商业需求。这两种贱金属都具有良好的特性，开发坚固的铝-钢结合可以降低汽车质量。更轻的汽车使用更少的燃料，向大气排放更少的碳。研究成果将使这项技术在汽车、航空航天和医疗设备等重要行业得到更广泛的应用。传统的焊接工艺会熔化待连接的金属，熔融混合会产生脆性金属间化合物，使得接头不适合大多数结构应用。冲击焊缝坚固而坚韧，是由两个金属表面之间的高速（通常为200-700米/秒）斜碰撞在固态下形成的。本研究的目的是：1)了解飞片的厚度（以及其总动能）如何影响形成的界面结构；2)了解冲击焊接过程中界面应变、温度和形貌的实时演变；3)将变形历史与焊缝的最终结构和性能联系起来。使用独特的工具来研究25微米至25毫米厚度的铝-钢冲击。最薄和最厚的飞片分别采用激光冲击焊和爆炸焊，而几种中间厚度的飞片采用汽化箔促动焊加速。光子多普勒测速技术将能够详细测量碰撞的速度和角度。基于光滑粒子流体力学和任意拉格朗日-欧拉方法的有限元模型将用于解决这些问题。通过焊接组织的金相检验和与模拟的比较，验证了这些方法的有效性。这些模型将用于理解材料应变，温度和结构的复杂动态发展，并在广泛的长度尺度上。