Mixed mode I-III fracture resistance of stainless steel 316L weakened by V-notches with end holes. (December 2022)

• Record Type: Journal Article
• Authors: Torabi, A.R.; Talebi, Hossein; Ayatollahi, M.R.; Petru, Michal
• Is Part Of: Theoretical and applied fracture mechanics. Volume 122(2022)
• Publication Date: 2022-12
• Subjects: Stainless steel 316L -- V-notch with end hole -- Notch fracture toughness -- Fictitious Material Concept (FMC) -- Mixed-mode I/III loading; Fracture mechanics -- Periodicals; 620.1126
• DOI: 10.1016/j.tafmec.2022.103574
• Languages: English
• ISSNs: 0167-8442

Abstract

Highlights: Mixed mode I/III fracture resistance of VO-notched stainless steel 316L is studied. A previously proposed test fixture is modified to perform the fracture tests. Original tests are performed for various mixtures of mode I and mode III loading. Fictitious Material Concept is linked to brittle failure criteria for predictions. With about 87% accuracy, both FMC-MTS and FMC-MS models are shown to be successful. Abstract: Notch fracture resistance of stainless steel 316L is investigated under mixed-mode I/III loading. A previously proposed test fixture, utilized in the past for testing low/medium toughness polymeric and metallic materials, is first modified to make it appropriate for testing significantly tough materials like stainless steel 316L. Then, original fracture tests are carried out on a specific sample weakened by V-notches with end holes (VO-notches) and loaded under different combinations of tension and out-of-plane shear, from which the critical loads and the fracture behaviour are extracted. Due to great strain-hardening and significant strain-to-failure for stainless steel 316L, the Fictitious Material Concept (FMC) is first employed to avoid complexities associated with fracture prediction. Then, FMC is combined with the maximum tangential stress (MTS) and mean stress (MS) criteria to predict the notch fracture toughness values determined experimentally. With approximately 87 % and 86 % accuracy in estimation of the mean experimental results, both combined criteria, called FMC-MTS and FMC-MS, are revealed to be successful.