Experimental and numerical study on dynamic fracture behaviour of AISI 1045 steel for compressor crankshaft

Abstract

Dynamic fracture behaviour of AISI 1045 steel for compressor crankshaft was studied by experimental and numerical methods. True stress–strain relations of the material under different strain rates were measured, and dynamic constitutive model with consideration to strain‐hardening and strain‐rate hardening was proposed. Dynamic fracture tests loaded by Hopkinson pressure bar were carried out, and fracture toughness was determined using a finite element method with the combination of ABAQUS and Zencrack software. Loading states of the specimen and determination methods of the dynamic fracture toughness were discussed. By comparing the fracture behaviours under quasi‐static and dynamic conditions, it was found that the fracture modes exhibited a transition from ductile to brittle fracture with the increasing loading rate, and the dynamic fracture toughness value was less than the quasi‐static one.

Experimental study on dynamic fracture behavior of AISI 5140 steel over a wide range of loading rates

“…However, when the loading rate was greater than 1.8778 MPa.m 0.5 , the dynamic fracture toughness rose due to the effect of thermal softening near the crack tip. Additionally, Wu et al 14 conducted an experimental study on fracture behavior of AISI 1045 steel. The fracture modes exhibited a transition from ductile to brittle fracture with the increasing loading rate, and the dynamic fracture toughness was less than the quasi-static one.…”