CORRECT HEAT TREATMENT FOR THE PRODUCTION OF CASTINGS OF THE ALLOY ASTM A494 42Ni-21.5Cr-3Mo-2.3Cu[R]
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The observed fractures are caused by the formation of a continuous network of NbC-Mo2C;
The INCOLOY 825 alloys for the production of casting are more sensitive to the observed detrimental phenomena because they are featured by a higher concentration of Nb (as a strengthening and stabilizing element) than the alloy used for forging;
the solubilization of the alloy for te foundry application has to be performed at leat at 1180°C to avoid the formation of an interconneted carbide network that induces brittleness in the castings.