1. Brief introduction of investment casting Inve […]
1. Brief introduction of investment casting
Investment casting is also called "lost wax casting". Generally, it is coated with multiple layers of refractory insulation material on the surface of the wax mold. After the bottom is hardened and dry, the wax mold in it is melted to form a molded shell, and then undergoes burning Afterwards, pouring is carried out to obtain castings. Because the obtained castings have higher specification precision and surface smoothness, it is also called "investment precision castings". 8 According to the difference of shell materials, melting Mold casting can be divided into:
Silica sol forging process; water glass casting process; composite forging process: composite processing process is a casting process that is close to the middle of sodium silicate and silica sol; it refers to the double-layer application of silica sol before the shell dipping , The method of applying sodium silicate after multilayer
1. Wax mold forging
A process of investment casting manufacturing is to produce wax molds. Wax molds are used to produce the solid model of the concave mold in the fireproof shell. Therefore, to obtain castings with high specification precision and surface smoothness, the wax mold itself It should have high specification precision and surface smoothness. In addition, the characteristics of the wax mold itself should also be as effective as possible to make the subsequent molding shell and other technological processes.
2. Shell manufacturing
It can only be formed into a thin shell of 1~2mm after slurrying, sanding, and hard bottoming. In order to make the shell have a higher compressive strength, the whole process of forming must be repeated 6~7 times. 12mm fireproof shell
In order to remove the wax mold from the mold shell to create a metal mold cavity, be sure to carry out dewaxing. Generally, the mold shell is soaked in a sulfuric acid solution at 85-95°C for 30 minutes up and down to melt the wax and remove it through the upward adjustment of the glue inlet. The slipped wax material can be reused many times after being purchased and resolved.