Sand casting technology for titanium, zirconium and nickel and alloy casting thereof

Abstract

The invention discloses a sand casting technology for titanium, zirconium and nickel and an alloy casting of the titanium, zirconium and nickel. The sand casting technology comprises steps of: (1) preparation of casting sand: adding bauxite powder, bauxite sand and silicate powder to a sand mixer, agitating for 3 to 4 hours, then adding silica sol, and finally adding dextrin, so as to obtain the casting sand; (2) modeling: manufacturing a die according to the casting technology drawing; (3) drying to obtain a casting mold: transferring the sand casting which is naturally and completely dried in the step (2) into an oven or a resistance furnace for roasting, so as to form the casting mold; (4) preparation of fire-resistant paint; (5) preparation of a fire-resistant coating: spraying the agitated paint on the surface of the casting mold which is contacted with the molten liquid during pouring; (6) roasting at a high temperature: transferring the casting mold which is naturally and dried in the step (5) into the resistance furnace for roasting; and (7) smelting and pouring: smelting and pouring in a vacuum kish self-consuming furnace for smelting and pouring. By adopting the sand casting technology, various castings of different dimensions can be produced in a large scale; the surfaces of the castings are free of defects such as cold shuts, current ripples and cracks; and the insides of the castings are free of the defects such as shrinkage cavities and inclusions.

Description

technical field [0001] The invention relates to a casting sand casting process, in particular to a sand casting process of titanium, zirconium, nickel and alloy castings. Background technique [0002] Titanium, zirconium, nickel and their alloys are relatively expensive metal materials, which have excellent corrosion resistance in many strong corrosive media and good mechanical properties. Titanium and zirconium materials are very active at high temperatures, and can chemically react with almost all refractory materials to varying degrees, and zirconium materials are very easy to react with CO at high temperatures. 2 , O 2 , N 2 and H 2 The chemical reaction of the gas will embrittle the zirconium material and cause the equipment to fail. This makes the casting of titanium, zirconium, nickel and their alloys must use casting materials with high chemical stability to ensure that the metal does not chemically react with the casting mold and has a small surface contaminatio...

AI Technical Summary

Problems solved by technology

The cost of machining graphite casting is high. Graphite casting has fast heat conduction and has a chilling effect on liquid metal, and defects such as cold shut and flow marks are easy to form on the surface of castings; investment precision casting is characterized by high surface quality of castings, suitable for complex thin Wall castings, but the production process is relatively complicated, the production cycle is long, and the thickness of the coating is limited. It is not suitable for pouring large titanium, zirconium, nickel and their alloy castings