Titanium alloy forging cleaning process

In all titanium alloys, the oxide rust and α shell formed during forging heating treatment are brittle and cause cracks during subsequent forging or final forging or tool wear during subsequent machining. Therefore, z should clean the rust and α shell between continuous forging and must be removed before the forgings are delivered to the user.

The cleaning technology of titanium alloy forging has two aspects: one is the removal of oxide skin; The second is the clearing of alpha shells. Rust can be removed by mechanical methods, such as sand blasting; Or by chemical methods, such as melting salt derusting. The choice of rust removal method depends on the size, complexity and cost of the part.

Sand blasting is an effective method to remove rust skin, it can remove 0.13 ~ 0.76mm thick rust skin, 100 ~ 150 mesh zirconium sand or steel sand, air pressure up to 275Pa. Although sandblasting can be used for forgings of various sizes, it is mostly used for medium and large titanium alloy forgings. Sand blasting equipment may be equipped with abrasive roller, shot blasting or sand blasting devices. After sandblasting, acid washing is required to remove the alpha shell.

Salt dissolving is another effective method to remove the oxide skin, and the α-shell is also removed by pickling. The flow chart, composition of solution and related parameters are usually used to remove rust and pickling with dissolved salt. The shelf used for salt derusting is generally made of wood, titanium or stainless steel, in order to prevent the generation of electric potential between the workpiece and the shelf, and the electrical erosion of the workpiece or the generation of arc. Dissolved salt rust removal is often used for medium and small forgings. In the case of mass forgings, the operating system can be fully automated.