Application of various low cycle fatigue evaluation rules to notched compact tension specimen test data

• Published in: The International journal of pressure vessels and piping Vol. 209; p. 105151
• Main Authors: Yoo, Kyoung-Chan, Song, Hyun-Seok, Lee, Jong-Min, Kim, Yun-Jae, Kim, Jin-Weon
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.06.2024
• Subjects: Conservatism in fatigue life evaluation; Elastic-plastic FE analysis; Experimental validation; Low cycle fatigue evaluation methods; Elastic-plastic FE analysis; Low cycle fatigue evaluation methods; Experimental validation; Conservatism in fatigue life evaluation
• ISSN: 0308-0161; 1879-3541
• DOI: 10.1016/j.ijpvp.2024.105151

Existing low cycle fatigue evaluation methods are applied to notched C(T) specimens test data of low alloy and stainless steels to quantify conservatism embedded in evaluation methods. Three methods are considered: American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel (B&PV) Code Sec. III simplified elastic-plastic analysis method, elastic-plastic fatigue analysis method given in the Japan Society of Mechanical Engineers (JSME) Code Case (CC) and elastic-plastic fatigue analysis method using the cyclic void growth-shrinkage model (CVGSM). The conservatism is quantified via cumulative usage factor (CUF). The simplified elastic-plastic analysis method given in ASME B&PV Code Sec. III is the most conservative. Using the best-estimate fatigue curve, calculated CUF values are around 5 to 7 using the simplified elastic-plastic analysis method. Elastic-plastic fatigue evaluation methods improve the accuracy. Calculated CUF values decrease to 2 to 3 when the JSME Code Case and the CVGSM are used. Effects of the cyclic hardening model for elastic-plastic finite element (FE) analysis and material input data (fatigue curve or fracture strain) on calculated CUF values are also investigated. •Conservatisms embedded in existing low cycle fatigue evaluation methods are quantified using notched C(T) specimens test data of low alloy and stainless steels.•Simplified elastic-plastic analysis method and elastic-plastic fatigue analysis methods are considered.•The conservatism is quantified via cumulative usage factor (CUF).•Effects of the cyclic hardening model for elastic-plastic FE analysis and material input data (fatigue curve or fracture strain) on calculated CUF values are considered.•The simplified elastic-plastic analysis method given in ASME B&PV Code Sec. III is the most conservative and elastic-plastic fatigue evaluation methods improve the accuracy.