Hadfield Steel Cast Structure Homogenization
A specific solution annealing process followed by quenching to eliminate carbide precipitations and macroscopic segregations in the as-cast condition. It restores the pure austenite microstructure.
In the annealing process, the casting is heated high in a closed container so that the carbides and segregations go back into solution. Then you quench it so that the structure stays stable as pure austenite – that's the critical step. If you don't get that right, you'll quickly get hot cracks or fractures when welding because the carbides remain at the grain boundaries. Make sure you don't anneal too long or miss the temperature, otherwise you'll distort the part or the homogenization will be incomplete. Stick to the specified time and temperature, then the structure will be uniform and weldable.