NDE Characterization on the Heat Treatment in Piston Rods for a Use of Shock Absorbers Using a Simple Automatic Ultrasonic System

Piston rods are key components that absorb shock and vibration energy, and provide handling stability while automotive wheels are rolling. A high-frequency heat treatment process guarantees the surface-hardening durability of piston rods. The Rockwell hardness test is performed to evaluate the degree of surface heat treatment. However, this test does not determine the hardening of the whole surface because only a part of the piston rod surface is tested. Thus, a proper nondestructive method was developed for inspecting the whole surface. The beam profile behavior was predicted by measuring the 360° full profile surface ultrasonic behavior using Rayleigh ultrasonic waves. We implemented a contact-type jig to measure the hardness, developed a simple automated operating system, and data signals were processed with LabVIEW. Finally, we implemented the ultrasonic behavior and optimal test conditions through FEM 3D simulation to produce Rayleigh ultrasonic waves. KCI Citation Count: 0