Precise investment casting powder and investment casting and moulding process thereof

Abstract

The invention discloses precise investment casting powder and an investment casting and moulding process using the same. The precise investment casting powder comprises the following raw materials in percentage by weight: 25 to 35 percent of alpha semi-hydrated gypsum powder and 65 to 75 percent of quartz powder. After the two raw materials are mixed, based on the weight of the mixture, 0.2 to 0.6 part of superplastieizer, 0.1 to 0.3 part of water reducing agent and 0.2 to 0.5 part of antifoaming agent are added into 100 parts of the mixture. The materials are uniformly mixed to form the finished product, namely the precise investment casting powder. The investment casting and moulding process comprises the following steps: according to the precise investment casting powder prepared from the raw materials, adding 38 to 40 percent of water into 100 percent of the precise investment casting powder, stirring the mixture to form paste, pumping air out of the paste, pouring the paste into a mould to perform vacuum treatment moulding, solidification and baking at a high temperature, and casting the molten metal to cast a cast product or store the molten metal for later use.

Description

technical field [0001] The invention relates to the field of manufacturing and molding of investment casting powder, in particular to a precision investment casting powder and a process for using the precision investment casting powder for investment casting. Background technique [0002] The Chinese patent number is 97108121.2, the patent publication number is CN1203128, and the publication date is December 30, 1998. The invention and creation of a patent named "practical precision investment casting powder and molding process" discloses a practical precision investment casting Casting powder and molding process, use hemihydrate gypsum powder, that is, plaster of paris and quartz powder to mix evenly. When molding, add a certain amount of water, shape, solidify, bake, and reserve. The disadvantage is that this product only takes the main material and does not Adding chemical additives will not achieve the effect of precision casting. A large number of air bubbles will be ge...

AI Technical Summary

Problems solved by technology

[0002] The Chinese patent number is 97108121.2, the patent publication number is CN1203128, and the publication date is December 30, 1998. The invention and creation of a patent named "practical precision investment casting powder and molding process" discloses a practical precision investment casting Casting powder and molding process, use hemihydrate gypsum powder, that is, plaster of paris and quartz powder to mix evenly. When molding, add a certain amount of water, shape, solidify, bake, and reserve. Adding chemical additives will not achieve the effect of precision casting. If gypsum plus quartz and water are used to stir the slurry, a large number of air bubbles will be generated, and the mold shell made will have a large number of pores. The cast product will have low precision and poor brightness.