Experimental and Numerical Analysis of Formation, Evolution, and Distribution of Residual Stress During Deep Cryogenic Treatment

A coupled thermo‐mechanical‐metallurgical finite element model (FEM) and X‐ray diffraction (XRD) measurement are employed to analyze the formation, evolution, and distribution of residual stress during deep cryogenic treatment (DCT) of SDC99 cold work die steel. Both the simulation and experimental analysis reveal that DCT reduces temperature difference between the surface and the core. DCT reduces the retained austenite content from approximately 15% to 2% by promoting its transformation. Residual stress evolution is governed by interaction of thermal and phase transformation stress. During conventional heat treatment (CHT), thermal stress dominates at its initial stage, while transformation stress becomes predominant at the later. During DCT, treatment lowers the overall stress level and improves stress distribution homogeneity through uniform release of transformation stress. Both experiment and simulation confirm that DCT effectively reduces tensile residual stress and increases compressive residual stress, especially in the tangential direction. The maximum tensile stress from simulation decreases by approximately 24.2%, 19.6%, and 6.5% in the tangential, longitudinal, and axial directions, respectively. Accordingly, the maximum compressive stress increases by about 70.7%, 28.2%, and 4.1% in the corresponding directions. The established multifield FEM shows good predictive accuracy, serving as a reliable tool for targeted control of residual stress distribution during DCT.