Effect of Auxiliary Vibrations on Weld Pool Solidification Kinetics and Mechanical Properties of Shielded Metal Arc Welded AISI 202 Stainless Weld Joints

Effect of auxiliary vibrations on weld pool solidification kinetics and mechanical properties of shielded metal arc welded AISI 202 stainless weld joints

 

Authors: Pravin Kumar Singh¹ & A. S. Shahi²

Affiliations: ¹Corresponding author (Email: pravin_sliet@rediffmail.com)

²(Email: ashahisliet@yahoo.co.in)

Mechanical Engineering Department, SLIET,Longowal District. Sangrur, Punjab, India (Pin 148106)

 

Abstract

This work reports the results of the experimental investigations that were carried out to study the influence of inducing auxiliary vibrations into the weld pool during butt welding of 10 mm thick AISI 202 stainless steel plates using SMAW process. An auxiliary vibratory set up was developed which could be mechanically vibrated by a primary vibratory source which resulted into vibrations of around 150 Hz. A single V joint design was selected, and low and high heat input combinations were used to fabricate the butt joints. While welding was carried out, the motion of the vibratory tip was immersed in the weld pool. The mechanical strength of these joints was evaluated by conducting transverse tensile test, Charpy test and micro hardness test. Microstructural studies were carried to study the changes in the solidification of the weld zone.

Tensile testing results show that the weld joints fabricated with vibratory condition were found to possess yield strength of 409.86 MPa as compared to the conventional yield strength of 367.31MPa and ultimate tensile strength increased from 576.78MPa to 606.47 MPa, without any appreciable loss in the ductility.

Charpy V impact energy absorption by the weld metal increased from 48 J to 56 J.

Metallographic studies conducted on the welded specimens show that weld metals subjected to vibratory condition had undergone grain refinement. HAZ (heat affected zone) also changed from coarse grained to a fine grained one. Micro hardness results further show that weld zone under vibratory condition possessed relatively higher hardness as compared to the conventional weld zone.