Determination of the forging-heating schedule or a large “HASTELlOY” alloy X ingot

Abstract

The thermal stresses generated by nonuniform temperature distribution during the heating of cold large-diameter HASTELLOY alloy X ingots were determined; the stress figures were obtained by way of temperature profiles calculated during representative heating cycles. The thermal stress along the longitudinal axis at the center of the ingot (in tension) was selected as the critical parameter, and a maximum allowable stress of 90 pct of the 0.2 pct yield strength was imposed to avoid fracture. From this analysis, a heating practice which maximizes the in-furnace heating rate and still avoids ingot fracture can be designed.