Source: ETMM-online
Heat treating plays a critical role in the making of a mold base, notes an Austrian manufacturer of standard parts for mould bases and die sets in a recent process profile in ETMM-online.
An excerpt:
"Heat-treat[ing] all steel plates for stress relief . . . at approximately 580°C [1076°F] for 24 hours . . . creates optimal conditions for low-deformation processing of parts. . . . With stress-relieving heat treatment, the tension in the material is minimized without changes to the microstructure or strength. This is a great advantage during subsequent machining. If there was still tension in the material, it would, for example, cause deformation during sawing or milling. During stress-relieving, it is important to heat the plates slowly and consistently and then maintain this temperature for six hours."
Read more: "Producing the Ideal Material for Making a Mould Base"