Microstructural evolution and metallurgic reactions in dissimilar joints of Nitinol wire and medical alloys during laser microwelding

医疗器械的制造和制造是一个巨大的领域，其中设备的不同部件的物理连接需要满足一定的标准。这就要求它们应该具有适当的机械强度和功能特性，这取决于它们的应用。贝利斯医疗公司(Baylis)的S射频(RF)穿孔系统是在心脏和血管组织中创建可控穿孔的世界领先企业，通过提供创新、安全和有效的手术设备，该系统已成为全球黄金标准，甚至拯救了无数人的生命。这种世界领先的技术和设备的主要制造挑战之一是小规模地将镍钛形状记忆合金与其他医疗合金(例如不锈钢、PTIR)连接起来。滑铁卢大学和贝利斯大学提出的这项研究旨在系统地研究NiTi合金与不锈钢(SS)和PTIR合金的异种激光微焊接，以及激光微焊对NiTiPT高温形状记忆丝材的加工，以实现医疗器械应用的小部件的可靠组装；它还将加深对NiTi/SS和NiTi/PTIR接头在材料加工中的小规模激光焊接过程中的组织变化和相变的了解，并提高对母材和层间化学成分、激光焊接工艺参数和配置对焊接组织，包括IMC成形和力学性能的影响的了解。这一合作项目的实施将加速Baylis在加拿大的新产品设计从研发实验室走向行业规模，这将使加拿大的创新能力保持在领先地位，并使加拿大企业处于制造和医疗行业技术开发的前沿。

The manufacturing and fabrication of medical devices is a vast field in which the physical connection of devices' different parts is required to meet certain standards. This entails that they should have a pertinent level of mechanical strength and functional properties, depending on their applications. Baylis Medical Company (Baylis)'s Radio Frequency (RF) Puncture System is the world leader for creating controlled perforations in cardiac and vascular tissues and has been the world-wide gold standard or even saved countless lives through supplying innovative, safe and effective surgical devices. One of the major manufacturing challenges for this world leading technology and the devices is joining of Nitinol (NiTi) shape memory alloys to other medical alloys (e.g., stainless steel, PtIr) at a small scale. The proposed research between the University of Waterloo and Baylis is to systematically investigate the dissimilar laser microwelding of NiTi alloy to stainless steel (SS) and PtIr alloys, as well as laser microwelding enabled processing of NiTiPt high temperature shape memory wire to achieve a reliable assembly of small components for medical device applications; it will also deepen the understanding of microstructural changes and phase transformation of NiTi/SS and NiTi/PtIr joints during laser welding at a small scale in material processing, and improve the knowledge of the effects of base metal and interlayer chemical compositions, laser welding process parameters and configurations on the weld microstructure, including IMC formation, and mechanical properties. The implementation of this collaborative project will accelerate the new product design for Baylis moving from R&D laboratory to industry scale in Canada, which will keep Canada's innovation capability at the pioneer position and place Canadian businesses at the forefront of technology development in the manufacturing and medical industries.