Fracture detection on coach frame welding joints with piezoelectric composite coating

汽车工业公司（MCI）面临着一个问题，即在汽车运行时，在不剥离汽车涂层材料的情况下，检测汽车车架焊接接头处可能出现的断裂。此外，由于在维护期间通常发现多个接头断裂，因此希望他们首先识别哪个接头断裂，因为这可能导致其他接头处的断裂。本课题将设计一种压电复合涂层，并将其应用于客车车架结构的焊接接头上。涂层应易于涂覆在焊接接头的粗糙表面上，并在涂覆涂层的焊接接头发生断裂时自动发出报警信号。该技术是由我的研究小组开发和测试的，但它在真实的工程结构上的应用将在MCI的工程技术人员的帮助下进一步测试和证明。该项目的成功将有助于MCI节省裂缝识别的成本，而无需剥离客车的涂层材料。通过注意到第一次断裂的发生，该技术还可以指导MCI的维修计划，以避免进一步的框架断裂和昂贵的维修过程。

Motor Coach Industries (MCI) is facing a problem to detect possible fractures at coach frame welding joints while the coach is in operation and without stripping off the coating materials of the coach. In addition, since multiple joints are usually found to be broken during maintenance, it is desirable for them to identify which joint fractures first because it can lead to fracturing at other joints. In this project, a piezoelectric composite coating will be designed and applied on the welding joints of coach frame structures. The coating should be easily applied on the rough surface of the welding joints and will send warning signals automatically, when the fracture takes place on the welding joint that the coating is applied. The techniques is developed and tested by my research group, but its application on the real engineering structures will be further tested and proven with the help of the engineers and technicians from MCI. The success of this project will help MCI to save cost on fractures identification without stripping off the coating materials of the coach. By noticing the first fracture happening, the technique could also guide MCI's maintenance schedule so as to avoid further frame factures and the expensive repair progress.