KmTBCr26 is a high-chromium anti-wear white cast iron with high carbon content, chromium as the main alloying element, and excellent performance. It has good hardenability and corrosion resistance, and can be used for abrasive wear with large impact loads. The heat treatment process includes softening and hardening treatment: (1) softening treatment is softening temperature 950 ℃, softening time 10 hours; (2) hardening treatment: air quenching sample at 1000 ℃, and better comprehensive performance can be obtained when tempering at 460 ℃. mechanical properties. Also refer to: 200-300 ℃ low temperature tempering structure is composed of tempered martensite, retained austenite and carbide; 550-650 ℃ high temperature tempering structure is composed of carbide and eutectoid structure.
Heat treatment Usually, the metallographic structure of high chromium cast iron in the as-cast state is: austenite + martensite + carbide + pearlite. In order to develop the full hardness potential and optimum wear resistance of the material while at the same time imparting maximum toughness to the material, heat treatment is required. Usually the austenitizing temperature is about 960-980°C, and the temperature is kept for 2 to 4 hours (depending on the size of the ball). If 0.3-1.0% Cu is added, it must be kept for more than 6 hours to destroy the stability of austenite. Tempering treatment can be carried out in two temperature ranges, and tempering is carried out in the lower temperature range (200-300 ° C), the purpose of which is to temper the martensite obtained in quenching, thereby reducing fracture and Sensitivity to shock. In the state of high-impact abrasive wear, if you want to obtain austenite structure, under the ideal situation of chemical composition control, you only need to perform high-temperature aging treatment once to remove internal stress, which can meet the general needs. Conclusion Practical application and experiments show that it is suitable to produce grinding balls with high chromium cast iron materials, as long as attention is paid to the implementation of casting and heat treatment processes, the selection and control of chemical components, metallographic structure, and the matching of hardness and toughness during the production process, It can give full play to the efficiency of the material and meet the requirements of use.
Chemical composition of GB-KmTBCr26
| C(%) | Si(%) | Mn(%) | P(%) | S(%) | Cr(%) | Mo(%) | Ni(%) | Cu(%) |
|---|---|---|---|---|---|---|---|---|
| 2.3-3.0 | ≦1.0 | 0.5-1.0 | ≦0.1 | ≦0.06 | 23.0-28.0 | 0.0-1.0 | 0.0-1.5 | 0.0-2.0 |
Applications
- Abrsion Resisting Cast lron Low Alloy and High Alloy Grade
Country Code
- GB
Standard
- 8263
Steel Type
- KmTBCr26