High Mn(manganese) steel castings heat threatment

High Mn(manganese) steel, such as Mn13-1, Mn13-2, etc, are widely used to cast products with high wear resistant property. 

To longer the lifetime of such high Mn(manganese) steel castings, the cast products have to be heat treated properly. High Mn(manganese) steel is a kind of special steel. The heat treating process is also a little different from other steels. 

Below, there're some characteristics happened during high Mn(manganese) steel heat treating process,

*When high Mn(manganese) steel castings are heated to 650℃, the temperature increasing becomes slow due to the increasing rate of C and P factors. Carbon and phosphorus factors are closely related to the cracks caused by heating.

*After high Mn(manganese) steel castings are heated to 650℃-700℃, castings should keep the temperature stable for 1 to 2 hours. This will make the heat of the castings uniform, and stress relief. If the temperature is higher than 650℃, the heat will be higher than the elastic deformation of the Mn(manganese) steel, the Mn(manganese) steel will be in condition of plastic state. The carbide will be dissolved into the austenite structure. Thus to increase the strength and plastic state of the Mn(manganese) steel castings.

*Upon temperature of Mn(manganese) steel castings heat treating reached certain degree, the castings should be cooled quickly. Usually, it's much better to less than 1min from taking the Mn(manganese) steel castings from oven till put them into water. Thus, to ensure the temperature of castings no later than 900℃ before hardening.

*If the temperature of Mn(manganese) steel castings is too low before hardening, the carbide will be separated out from the castings and form a carbide layer on top of castings. When cooling the castings quickly, this layer will be broken and cause the crack problems.

*To get stable mechanical properties of High Mn(manganese) steel castings, the castings should be solution treated. It's also a kind of characteristics to heat treat the High Mn(manganese) steel castings.