Abstract

Many advantages of fiber reinforced polymer composites (FRPCs) make them suitable for various industrial applications, especially aerospace. However, they possess limitations, such as low thermal and electrical conductivity, as well as relatively low erosion resistance. This has led to in-service failure of FRPCs causing fatal accidents, as well as the waste of materials and equipment. In order to overcome these limitations, surface coating and metallization of FRPCs is a potential resolution. For this purpose, the incorporation of a metal wire mesh in the outermost layer of the composites forms a superficial anchor for the deposition of metals using thermal sprays, which has been proven to be an effective method. However, obtaining a proper surface coating is yet dependent on the mesh exposure level of the fully resin-covered metal mesh by surface preparation methods before the coating process. In this study, optimization of grit blasting parameters and introduction of operational parameter maps for preventing damage to the mesh pattern and composite during grit-blasting are carried out. An in-house automated sample holder for grit blasting process is designed and assembled allowing for better control over the grit blasting process. Then, the effect of grit blasting pressure, time, and stand-off distance at three levels on the exposure level of metal mesh were investigated through systematic experimentation. Portable digital microscopy and conventional optical microscopy are employed to inspect the composite surface and to measure the level of polymer removal at each processing condition. According to the results, it is practical to achieve a desirable metal mesh exposure following the optimized grit-blasting parameters. Moreover, developing a computer-aided inspection system can enormously contribute to the realization of uniform, and efficient grit blasting in industrial applications for huge structural parts.