Wear-resistant steel castings heat treatment step
To remove the cast structure of the carbide, shall steel heated to 1040. C and above, and holding an appropriate time to complete solid solution carbide phase austenite, followed by rapid cooling of austenite solid solution to get organized. This solution heat treatment process is also known as water tough.
(1) tough dealing with the temperature of water: water temperature depends on the tough high-manganese steel components, usually 1050 to 1100.
(2) heating rate: high manganese steel than the poor thermal conductivity, high manganese steel castings easily understood in a larger stress cracking when heated, so the heating rate should be based on the casting wall thickness and shape may be. Generally thin-walled castings can be simple and rapid rate of heating; thick-walled castings are advised to slow heating.
(3) holding time: holding time depends on casting thickness, to ensure that the cast structure is completely dissolved in the carbide and austenite homogenization. Usually holding time can be calculated casting wall thickness of 25mm insulation lh.
(4) Cooling: Cooling process for casting performance and organization of the state have a great impact, water processing and tough casting into the water before the temperature of 950. C will be on in order to avoid re-precipitation of carbides. To this end, the casting time from the water released to A should not exceed 30s; water temperature maintained at 30. C below. After quenching the maximum temperature does not exceed 60 degrees C. Water temperature on the mechanical properties of high manganese steel in Table 11-17, the high manganese steel at high temperature mechanical properties decreased significantly. Water, water to be tough to achieve when dealing with casting and hanging bar for more than eight times the weight, if the non-recycled water to increase water needs on a regular basis. Summer is good to use recycled water or clean water using compressed air to agitate the water. Quenched with a hanging basket, the basket can be a way to accelerate the swing casting cooling.
High manganese water treatment and tough multi-purpose trolley. Heat treatment furnace. Castings were used automatic rollover or water quench means hanging basket. The former large and thin-walled parts of complex shape can lead to deformation, after quenching the casting removed from the pool is also more difficult; latter convenient casting out after quenching, but the consumption basket.