How to improve the hardness of light burnt magnesia powder
The degree and hardness of light-burned magnesia powder are improved by heat treatment. The following provides various heat treatment effects. For light-burned magnesia balls, you can choose the appropriate heat treatment according to the situation. If you just want to increase the hardness, surface quenching is recommended. The purpose of normalizing ductile iron is to obtain the pearlite matrix structure, and to refine the grains and uniform structure to improve the mechanical properties of the casting. Sometimes normalizing is also the preparation for surface quenching of ductile iron. Normalizing is divided into high temperature normalizing and low temperature normalizing.
High normalizing generally does not exceed 950～980℃, and low temperature normalizing is generally heated to a common bending temperature range of 820～860℃. After normalizing, four people are required to deal with it to eliminate the internal stress generated during normalizing.
Light-burned magnesia powder has high mechanical properties. Generally, castings are heated to 30-50°C above Afc1 (Afc1 represents the final temperature of A formation during heating), and then quenched into oil after heat preservation to obtain martensite structure. In order to appropriately reduce the residual stress after quenching, generally, tempering should be carried out after quenching, and the structure of low temperature tempering is used for tempering Martens to add residual bainite and then add spherical graphite. This structure has good wear resistance and is used for parts that require high wear resistance and high strength.