A model to predict fatigue crack initiation in plates with a pre-crack

Article type: Research Article

Authors: Kumar, Prashant^a; | Shinde, Prakash S.^a | Pawar, Kuldeep^a

Affiliations: [a] Department of Mechanical Engineering, College of Engineering Pune, Shivajinagar, Pune, Maharashtra 411005, India

Correspondence: [*] Corresponding author. E-mail: prkumar@iitk.ac.in

Abstract: A model is proposed on a macro scale to predict crack initiation caused by a constant amplitude fatigue load. It predicts the number of cycles (Ni) required to initiate the crack at the tip of a pre-crack, sharpened with a razor blade, by the relation Ni = 𝛼(KImax)𝛽 where KImax is the stress intensity factor corresponding to maximum stress of the fatigue load and 𝛼 and 𝛽 are the material constants to be determined by experiments. The validity of the model was checked on thin sheets of commercial aluminium, copper and mild steel.

Keywords: Critical plastic strain, fatigue initiation cycles, pre-crack, constant amplitude fatigue load, crack initiation

DOI: 10.3233/SFC-180210

Journal: Strength, Fracture and Complexity, vol. 11, no. 1, pp. 19-29, 2018