Carburizing treatment
Carburizing treatment is one kind of heat treating processes for investment castings. Carburizing treatment can increase the content of carbon elements in certain layer of the castings. Thus, to increase the strength of the castings.
Processes of carburizing treatment,
Step 1, Decomposing
*Carburizing medium decomposing to achieve activated carbon atoms.
Step 2, Sticking
*The activated carbon atoms sticked to the austenite layer of the castings, which increase the carbon in the surface layer of castings.
Step 3, diffusing
*There will be difference on tensity of carbon between surface layer and core area, due to the carbon increasing on surface layer. Diffusing of carton depends on temperature and alloy elements of investment castings.
Application of carburizing treatment
Carburizing treatment is mostly used for low carbon steel and low carbon alloy steel(with C≤0.25%) casting. To achieve the most efficiency, the investment castings should be hardening treated after carburizing. After carburizing, the surface of the castings is combination of martensite, austenite and little carbide. The core of casting is low carbon austenite. The depth of the carburizing is usually 0.8mm - 1.2mm. Sometime, it can be 2mm deep. Surace hardness can be 30HRC to 42HRC. This increases the impact property and wear resistance of the castings, thus, to increase the lifetime of the castings.
If your products are with such service requirements, please contact us.