Interface Study of Explosive Welded AL-Steel Joint Using Ultrasonic Phased Array Technique

Abstract

Explosive welding is advantageous for joining dissimilar materials having large surface area with excellent metallurgical bonding. However after explosive welding, the major area which one needs to focus is the bonded and de-boned area inspection and evaluation. In this research work, pure aluminium (Al) plate is explosively welded with Mild Steel (MS) using explosive of low Velocity of Detonation (VoD) . The welded plates are then verified and examined through non-destructive testing technique named Phased Array based Ultrasonic Testing (PAUT) to check bonded and de-boned areas in welded plates. Optical microscope and Vicker’s micro-hardness tester was also studied for Al-MS joints. Successful bonding of bimetallic plates was observed and ultrasonic testing results also confirmed that maximum area was successfully bonded and only some area towards the end of detonation was left de-boned. Obtained results clearly reveal, explosive welding technique using explosive of low velocity of detonation, as a promising technique to join bi-metallic components, which has wide applications in industrial and defence sectors.