TY - JOUR
T1 - Exploring the effect of complex hierarchic microstructure of quenched and partitioned martensitic stainless steels on their high cycle fatigue behaviour
AU - Sierra-Soraluce, A.
AU - Li, G.
AU - Santofimia, M. J.
AU - Molina-Aldareguia, J. M.
AU - Smith, A.
AU - Muratori, M.
AU - Sabirov, I.
PY - 2023
Y1 - 2023
N2 - Recent studies have demonstrated the viability of quenching and partitioning (Q&P) treatment for processing martensitic stainless steels showing an improved balance of high strength and sufficient ductility. However, to date, the fatigue behaviour of these materials has not been explored. This study examines the effect of their complex hierarchic microstructure on high cycle fatigue performance. Three steels with different alloying element contents underwent Q&P processing, resulting in multiphase microstructures rich in retained austenite. High cycle fatigue tests and analysis of fatigue fracture surfaces were performed using SEM and EBSD techniques. The results indicate satisfactory high cycle fatigue performance in Q&P treated martensitic stainless steels, surpassing traditional counterparts. Fatigue cracks predominantly form and propagate along martensite packet and block boundaries, while prior austenite grain boundaries and MnS inclusions have minimal influence on fatigue crack formation and growth. Microplastic deformation at the fatigue crack tip enhances local KAM values and triggers localized transformation of retained austenite grains. It is hypothesized that the developed Q&P treated martensitic stainless steels exhibit improved resistance to low cycle fatigue.
AB - Recent studies have demonstrated the viability of quenching and partitioning (Q&P) treatment for processing martensitic stainless steels showing an improved balance of high strength and sufficient ductility. However, to date, the fatigue behaviour of these materials has not been explored. This study examines the effect of their complex hierarchic microstructure on high cycle fatigue performance. Three steels with different alloying element contents underwent Q&P processing, resulting in multiphase microstructures rich in retained austenite. High cycle fatigue tests and analysis of fatigue fracture surfaces were performed using SEM and EBSD techniques. The results indicate satisfactory high cycle fatigue performance in Q&P treated martensitic stainless steels, surpassing traditional counterparts. Fatigue cracks predominantly form and propagate along martensite packet and block boundaries, while prior austenite grain boundaries and MnS inclusions have minimal influence on fatigue crack formation and growth. Microplastic deformation at the fatigue crack tip enhances local KAM values and triggers localized transformation of retained austenite grains. It is hypothesized that the developed Q&P treated martensitic stainless steels exhibit improved resistance to low cycle fatigue.
KW - Crack initiation
KW - Crack propagation
KW - Fatigue limit
KW - Martensitic stainless steels
KW - Quenching and partitioning
KW - Retained austenite
UR - http://www.scopus.com/inward/record.url?scp=85170418423&partnerID=8YFLogxK
U2 - 10.1016/j.matdes.2023.112286
DO - 10.1016/j.matdes.2023.112286
M3 - Article
AN - SCOPUS:85170418423
SN - 0264-1275
VL - 233
JO - Materials and Design
JF - Materials and Design
M1 - 112286
ER -