Impact of microstructure morphology on fatigue crack initiation in 9Cr-1Mo (P91) through numerical simulation

• Published in: Procedia Structural Integrity
• Main Author: Rahim M.R.A.; Schmauder S.; Manurung Y.H.P.; Božić Ž.; Binkele P.; Dusza J.; Csanádi T.; Ahmad M.I.M.; Mat M.F.; Dogahe K.J.
• Format: Conference paper
• Language: English
• Published: Elsevier B.V. 2024
• Online Access: https://www.scopus.com/inward/record.uri?eid=2-s2.0-85195538700&doi=10.1016%2fj.prostr.2024.05.003&partnerID=40&md5=aa15c1df734d47a0ea40a4a0018c84ca

This study investigates the influences of the four different microstructure morphologies on the calculation of the fatigue crack initiation cycle number for 9Cr-1Mo (P91) under cyclic loading conditions at room temperature. Understanding the critical influence of microstructure behavior on material durability necessitates examining two principal microstructure morphologies: irregular microstructures with inhomogeneous and homogeneous grain shapes, which were generated using the Voronoi Tessellation (VT) method. Finite Element Method (FEM) simulations were conducted to identify different stress distributions across these artificial microstructures. These stress distributions were subsequently analyzed using the physics-based Tanaka-Mura model (TMM) to estimate the number of cycles for fatigue crack initiation at several stress amplitudes and four types of microstructure. The fatigue resistance of the homogeneous grain morphology was discovered to be higher than that of the inhomogeneous microstructure, indicating the possibility of developing more durable material designs. The investigation into the different microstructure morphology of steel P91 offers a significant advancement in fatigue research, particularly with implications for power plants. © 2024 The Authors.