Research on Difference of Fracture Splitting Performance and Quality Defect Analysis for 36MnVS4 and 46MnVS5 Connecting Rods

A comparative analysis was conducted on the fracture splitting processing performance of two types of high-strength connecting rods, 36MnVS4 and 46 MnVS5, which were made from non-quenched and tempered materials. The reasons that affected the quality of connecting rod cracking were explored, and the boundaries for connecting rods cracking processing were optimized. The impacts of the connecting rod structures on the fracture-splitting processing performance were analyzed as well. The distribution characteristics of principal stresses and plastic strains at the roots of the cracking grooves were analyzed, and the crack initiation positions for connecting rods made of different materials were determined. The crack propagation processes of the connecting rods were simulated using the finite element software ABAQUS and FRANC3D, and a comparative analysis was conducted. The loading speed for the cracking processing of the 36MnVS4 materials was optimized. The impacts of the connecting rod structures on the cracking performance were analyzed.The results indicate that under the same boundary conditions, the cracking performance of 46MnVS5 material is better, with the tendency to have a unique crack initiation position, low notch sensitivity, good fracture brittleness, faster crack propagation speed, and higher required crack load. At a loading speed of 25 mm/s, the cracking performance of 36MnVS4 material improves. Connecting rod structures with smaller theoretical fracture surface area exhibit relatively better cracking performance. © 2024 Chinese Mechanical Engineering Society. All rights reserved.