Papers by Keyword: Abrasive Blast

Abstract: Composite materials, such as CFRP, are hard-to-cut materials but useful for their specific strength. Usually creating small holes in them is done using drill tools, but tool abrasion occurs early, reducing quality, raising processing costs. Comparing drilling with other processing methods, it was revealed in a previous report that it was possible to effectively create large quantities of small holes using blasting [1]. However, such blast processing involves unknown mechanisms. In the present report, we investigated the material-removing mechanisms of blasting from the viewpoint of erosion abrasion, and looked into the most suitable method by changing hole sizes and processing conditions. The results revealed, relationships between abrasive particle size and hole accuracy or hole processing efficiency as well as the optimum abrasive combinations according to hole diameter.

Abstract: Carbon fiber-reinforced plastics (CFRP), which are now used in some aerospace applications, is difficult to cut and drill holes in. Moreover, no reports have focused on selecting a suitable drilling method for each aerospace part. This paper discusses many methods of hole generation for CFRP composites, including methods using traditional drill tools and non-traditional methods such as abrasive water jet (AWJ), laser beam and abrasive blast. We look at traditional cemented carbide material tools, polycrystalline diamond (PCD) tools, diamond-like carbon (DLC) coated tools and ceramic tools. Then, comparing the experimental results of these methods from the viewpoints of characteristics, efficiency, cost, and hole quality, we investigate each problem to select the suitable drilling method. As a result, we propose a novel method to strategically obtain the best solutions to generate holes in aerospace parts.

Abstract: Polycrystalline ingot slicing by wire electric discharge machining (W-EDM) has been investigated to reduce kerf loss and wafer thickness. In order to use the sliced wafers for semiconductor devices, the modified surface layer induced by W-EDM must be removed. In this paper, we have demonstrated the elimination of the layer by abrasive blasting. Three types of abrasives were blasted at a speed of 100 m/s. The surfaces blasted with WA #1000 and GC #1000 were smoother than that sliced with a wire saw. The modified layer induced by W-EDM slicing could be removed by blasting with WA #1000 while scanning the surface three times. Solar cells were fabricated using wafers with the blasted surface with an efficiency of 15.2%, which was almost the same as that of cells fabricated from the wire-sliced wafers.