Experimental investigation on influence of electrode vibrations on hardness and microstructure of 1018 mild steel weldments

Abstract

<jats:sec> <jats:title content-type="abstract-subheading">Purpose</jats:title> <jats:p>The purpose of this study is to explore the importance of vibrations during welding process. In recent years, welding has gained its supremacy in the field of production. The main set back of the welding process is induced residual stresses, which is a major cause for many welding defects. These defects can be minimized by post-weld heat treatment methods, which is a time consuming and laborious process. In the recent past, a technique of exciting the weld-pool by vibrating the work-pieces was also adopted to minimize the above-mentioned stresses. A novel technique of electrode vibration is another effective way of transferring the vibrations to the weld-pool to influence the induced residual stress.</jats:p> </jats:sec> <jats:sec> <jats:title content-type="abstract-subheading">Design/methodology/approach</jats:title> <jats:p>In this research, the electrode is vibrated with the help of an electric motor. The specimens were prepared as per American Society for Testing and Materials standards and welded with varying frequencies and voltages. The weldments are tested for hardness along the weld bead and heat affected zone, also the microstructure of the fusion zone is analyzed.</jats:p> </jats:sec> <jats:sec> <jats:title content-type="abstract-subheading">Findings</jats:title> <jats:p>It is observed that there is an improvement in the hardness because of the grain refinement, which is a result of proper excitation of the weld-pool. It is observed that there is an improvement in hardness test up to 28.69% when compared with the conventional welding process. The peak value of hardness is observed at a frequency of 4,450 Hz. This is because of fine grain structure at this frequency, which is observed through the microstructure analysis.</jats:p> </jats:sec> <jats:sec> <jats:title content-type="abstract-subheading">Originality/value</jats:title> <jats:p>A novel technique is introduced to refine the weld-pool through electrode vibrations. To improve the hardness of the welded joints, vibrations play a major role by refining the grain structure. The vibrations are imparted with the help of a special equipment attached to the electrode.</jats:p> </jats:sec>

[Retracted] Influence of Heat‐Treated and Vibratory‐Assisted Weld Joints on the Mechanical Properties of 304L SS Material

“…Because of the vibratory treatment, the crystals develop in a specified direction during welding. As a result of the grain refinement, the toughness of the weldment increased by 25% [23,24]. The effects of transverse oscillation frequency and amplitude on mild-steel weldment characteristics are explored.…”

The effect of vibratory conditioning on tensile strength and microstructure of 1018 mild steel

“…An observation in the microstructure at 12 V of weldments, the weld defects were identified which is the reason for diminished tensile strength is shown in Figure 13(a). Similarly, the electrode voltage is raised to 14 volts the voids were reduced when compared with the microstructure of the 12 V weldments is shown in Figure 13 (Bade et al, 2020). The fine grain structure is owing to the refined molten metal at fusion state with excitation at different voltages with respect to the frequencies.…”

The effect of post-weld heat-treatment (PWHT) and vibratory assisted welding (VAW) on hardness of 304L stainless steels material

“…Mechanical excitations to the vibrating table and electrode also have a significant effect on the mechanical properties of 1018 mild steel. The authors observed that stirring of weld pool with the mechanical excitations influences the hardness and ultimate tensile strength of the 1018 mild steel properties along with the grain structure [15][16][17].…”