Temperature Measurement Method of Friction Stir Welding Using Ultrasonic Time of Flight
Mohammed Shahdan, Mohd Adeeb
:
2012-04-20
Abstract
Temperature measurements of the weld during friction stir welding (FSW) have previously been carried out using various methods including infra-red imaging/ thermometers, embedded thermocouples in the parent metal as well as direct contact thermometers. These methods usually only measure the temperature of the surface of the metal or requires the drilling of holes and the addition of foreign material into the weld. Previous studies have shown that the sound speed in most materials is a strong function of temperature. This study investigates the use of the change in the time of flight (TOF) of ultrasonic pulses to measure the average temperature of the weld as the weld is being made. Experiments were done on Aluminum 6061 while a process FSW was being carried out. This study shows that the use of ultrasonic TOF to measure the temperature of welds during the FSW process is a very promising method that could replace the use of more commonly used methods such as thermocouples and infrared pyrometry.