Investigation On Gypsum Mould Based On Rapid Prototyping Precision-investment Casting

Rapid Prototyping technique is a new forming technology based on the discrete and accumulative principle. Plaster casting is a special foundry technique, it is defined that metal molten is pouring into the foundry mould mixture with gypsum, after molten freezing, the metallic part or mould can be obtained. Plaster precision casting combines with RP technique. can be use to found precise,complex,thin-wall nonferrous metallic parts who's character is the small roughness,the precise size and the light deforming.Some discussion and research on plaster precision-investment casting is made in domestic, but the plaster casting's applications in high temperature alloy is unusual. The character of plaster molding material analyses in the thesis, the process and characteristic of gypsum and quartz's crystals transition which generates in the roasting lucubrated; and research deeply in the plaster precision-investment casting based on RP technique; the foundry technique is optimized; A-alloy parts is made with the plaster precision-investment casting. The central achievement in the thesis is:â‘ The compounding of molding material used in plaster precision-investment is confirmed; good performance of the compounding is proved in the practical application; we applied the patent of invention about the molding material and the making mold technique using nonferrous metal casting.â‘¡According to the requirement of vacuous grouting and pouring used in the plaster casting, we designed and manufactured the equipment used for grouting slurry and pouring metal molten in production. The processing parameter about plaster molding is confirmed and a mew operational standard about vacuous grouting slurry and pouring metal molten is instituted.â‘¢The mold making and casting technique of gypsum mould is optimized; the processing parameter of the gypsum mould's roasting is confirmed.â‘£A-alloy precision-investment with gypsum mould is explored and experienced; the making of some complex structural parts, such as the shelling parts of an airplane and the SANY auto cycle's crank plate., is produced.