WJ Forming: a preliminary study

摘要

The AWJ/WJ technology has shown, in recent years, a substantial development in the applications and a sensible improvement in the performances. Beside 2D or 3D cutting of any kind of material, there are new applications for the AWJ/WJ technology such as rapid prototyping, surface treatments etc. A new application of WJ technology, that can have promising developments in the field of the rapid prototyping, is the WJ forming. An elastic strain is applied to a low thickness metallic slab, clamping it along its perimeter to a frame having the adequate shape in order to give to the sheet the configuration it has to take after a spring back at the end of the treatment; at this point, regulating the technological parameters in function of the required energy, the impact of the water jet, following suitable paths, can generate on the slab a sufficient surface plastic strain in order to keep the defined shape also after removing the clamping devices (the process does not require dies) until now this kind of sheet forming is made by shot peening deformation, where the sheet, along its perimeter to a frame clamped, is over and over again stricken by high speed steel spheroids, which are carried by high pressure air. Using the WJ forming technology instead of the shot peen deformation it is possible to avoid the indentation of sheet surface and it is possible to reduce the sheet thickness you can deform. In this paper the preliminary analysis of WJ forming is carried out in order to determine the most important factors which influence the process.