Investment casting method

Abstract

The invention provides an investment casting method. Firstly, a pressure mold is produced; then, a wax mold is pressed, and pasty wax is pressed in the pressure mold by pressure and taken out after being cooled and condensed; a refractory material coats the surface of the wax mold to form a rigid shell through main steps of paint dipping, sand spreading and hardening; the process of forming the rigid shell is repeated again and again to form the hard refractory shell with the thickness of 5-10 mm; when the sand spreading is performed, the particle size of later layers of sand is greater than the particle size of first and second layers of sand; and after the rigid shell is formed, the wax mold is dipped in water of 85-95 DEG C with a gate facing upwards so that the wax therein is melted to float on the water surface, or the shell is put in a high-pressure kettle with the gate facing downwards, and steam of 0.2-0.5 MPa is fed to the high-pressure kettle so that the wax is melted and led out. The investment casting method is precise in casting mold, has no parting surface, and can cast high-melting-point alloys and difficultly cut alloys; and the cavity surface is smooth, so that the preciseness and surface quality of castings are excellent.

Description

technical field [0001] The invention relates to an investment casting method, which belongs to the technical field of machinery. Background technique [0002] In the prior art, the general small and medium-sized enterprises adopt the sand casting method for parts with relatively complicated structural shapes. Although the sand casting method can adapt to various parts with complex shapes, the quality of the manufactured products is not good, and the dimensional accuracy is relatively low. Low, there is a parting surface on the product, it is difficult to adapt to the requirements of modern machine manufacturing. Contents of the invention [0003] The invention provides an investment casting method, which can overcome the above-mentioned defects, does not need molding sand, has no parting surface, has high dimensional accuracy and good quality. [0004] In order to solve the above technical problems, the present invention provides the following technical solutions: an inve...

AI Technical Summary

Problems solved by technology

[0002] In the prior art, the general small and medium-sized enterprises adopt the sand casting method for parts with relatively complicated structural shapes. Although the sand casting method can adapt to various parts with complex shapes, the quality of the manufactured products is not good, and the dimensional accuracy is relatively low. Low, there is a parting surface on the product, it is difficult to adapt to the requirements of modern machine manufacturing