How much hardness is better for the mold pad of aluminum profile extrusion machine?

For the mold pad of the extruder, the backing plate used for the transition between the mold and the machine table does not need to be too hard, but it needs to have sufficient thickness and area. If the backing plate is too hard, it will damage the working table of the machine tool. Specifically, it depends on how many tons of extruder is used? Then choose the appropriate material for the mold mat.

Suggestion: Cr12MoV is used as the backing plate in the mold, quenched to 55HRC. It is recommended to use 40Cr as the backing plate between the machine tools of the mold, the area should be large and the thickness should be thick, and the hardness should be quenched and tempered to 28HRC. This protects the machine table top from damage.