Superplastic forming process

摘要

A method is disclosed for stretching sheet blanks, especially superplastic sheets, by differential gas pressure into conformity with a female die surface without encountering excessive thinning or tearing of the sheet. The warmed SPF sheet is draped over a preformed surface to draw more of the sheet material into the die cavity before the edges of the sheet are fixedly clamped whereby the additional formable material is used in forming the product, thereby reducing thinning and tears.