Casting process for forming complex pipeline in titanium alloy investment casting

Abstract

The invention discloses a casting process for forming a complex pipeline in a titanium alloy investment casting; and the process comprises the steps of: preparation of a pipe, parting and manufacturing of a wax mold, combination of the wax mold, roasting after steam dewaxing, and casting after laying a titanium pipe in a mold shell. The pipe formed by the process has no gap with a main body; the sealing and pressure resisting requirements of the pipe can be satisfied; the formation of the pipe is more flexible compared with a ceramic core and direct coating; the forming process requirements of pipes with various shapes of castings can be satisfied; the casting process difficulty is reduced; after the process is performed, the defects of cleaning difficulty and use limit are overcome, the casting surface quality is guaranteed, the production period is shortened, and the casting production cost is saved; and as the titanium pipe is inlaid after high-temperature roasting of the mold shell, the deformation in the casting process is reduced, and the casting quality is further improved.

Description

technical field [0001] The invention relates to the field of precision investment casting, in particular to a casting process for forming complex pipelines in titanium alloy investment castings. Background technique [0002] In the existing titanium alloy investment casting production technology, the traditional titanium alloy casting pipeline is mainly formed by the method of core forming. There is no more than one position with a diameter ≥ φ20 and a curvature greater than 90 degrees, and it is generally formed by direct coating method; the diameter is between φ10 and φ20, the length is ≤ 100 and the position with a curvature greater than 90 degrees is not more than two. For simple pipelines, ceramic cores are generally used; for long pipelines with a diameter ≤ φ10 and complex shapes, the above two process schemes will have the following problems in the actual operation process: 1. The ceramic core and mold shell forming the pipeline are not easy to remove. It is easy to...

AI Technical Summary

Problems solved by technology

There is no more than one position with a diameter ≥ φ20 and a curvature greater than 90 degrees, and it is generally formed by direct coating method; the diameter is between φ10 and φ20, the length is ≤ 100 and the position with a curvature greater than 90 degrees is not more than two. For simple pipelines, ceramic cores are generally used; for long pipelines with a diameter ≤ φ10 and complex shapes, the above two process schemes will have the following problems in the actual operation process: 1. The ceramic core and mold shell forming the pipeline are not easy to remove. It is easy to damage the inner wall of the pipe during the cleaning process; 2. The core is easily broken and eccentric under the violent impact of titanium liquid, resulting in uneven wall thickness of the casting pipe, under-casting and runaway; 3. It is difficult to position the ceramic core in the mold , easy to eccentric or break; 4. It is very difficult to clean the paint in the complex pipeline formed by the paint, and it is basically impossible to realize; 5. In the wax mold stage, bury the titanium tube in the corresponding position or directly place the titanium tube in the mold and inject it directly Wax forms a wax mold. When the mold shell is roasted at high temperature in the later stage, the titanium tube is prone to oxidation and cracking, resulting in unqualified castings.

Images