High Speed Tensile Test and Fracture Analysis of EV Drive Motor Shaft Produced by Radial Forging

User Benefits

- It is possible to evaluate the velocity (strain rate) dependence of mechanical properties and identify inclusions in metallic materials. - High-speed tensile tests at up to 20 m/s can be conducted by HITS-TX. - EPMA enables elemental analysis on uneven fracture surfaces to be performed as is.

Introduction

Radial forging is a new forging method for hollow shafts and is used in various fields such as transport equipment, medicine, and tools. In radial forging, while a hammer (mold) applies force from the radial direction of the shaft to deform it plastically, core metal can be inserted and the internal shape can be transferred, making it possible to form both internal and external diameters simultaneously. Processed hollow shafts can achieve both strength increase and weight reduction, and this is attracting attention as a manufacturing method for next- generation shafts, especially in the transportation field. Considering such applications in transport vehicles, it is necessary to evaluate the impact characteristics and the velocity dependence of mechanical properties. In a previous article, static tensile tests were conducted using test pieces obtained from radial forging products and the blank before processing. In this article, test pieces were collected in the same way, and the velocity dependence of mechanical properties was evaluated using HITS-TX high-speed impact testing machines. Fracture surface observation and elemental analysis of the fractured test pieces were also performed using an electron probe microanalyzer (EPMA).

September 5, 2023 GMT