Optimization of heating cycles prior forging for large steel ingots based on a simulation model

A simulation model has been used to calculate temperature distribution and internal stresses of steel ingots. The aim of this study is to optimize the heating cycles without compromising the mechanical integrity of the ingots, which ideally will result in a reduction in energy consumption and an increase in furnace productivity. The heating cycles of three ingots of different materials (ASTM A105, AISI 4330, and AISI 8630) and sizes (1.60, 1.75 and 1.32 m) are optimized. The optimization procedure of the heating cycle is based on a time reduction at each step of the set point. The phase transformation temperature at the ingot center was taken as a reference because this is where the higher stresses are developed. A sample of a 1 m Ø AISI 8630 ingot was characterized with a Scanning Electron Microscope, Energy-dispersive X-ray Spectroscopy, X-Ray Diffraction, and Differential Scanning Calorimetry. Results show precipitates in the as-cast condition, which will eventually be dissolved after a complete heating cycle.