Growth of Intermetallic Compunds in Rotary Friction Welding of Aluminium and Steel, Assisted with Preheating by Eletromagnetic Induction

Abstract

Welding of dissimilar aluminum and steel joints can be achieved by friction process, which is a solid state welding process. This process occurs at temperatures below the melting point of the metals, and have as main bonding mechanism, diffusion. It is an interesting bonding process option because it generates low residual stress, less distortion and low crack formation. However one of the major challenges of weld dissimilar materials is the no formation of intermetallic compounds, which can reduce the mechanical strength of the joints. This work presents the butt welding by rotary friction of Aluminum ASTM A6351 T6 and SAE 1020 Steel. It aims to evaluate the growth of intermetallic interlayers, without the use of steel preheating, and also with steel preheating. It also aims to evaluate structures obtained and the results of tensile strength. To achieve the objectives, a conventional friction welding machine was developed for research. The preheating of the steel was performed by electromagnetic induction. The welded joints were submitted to tensile and metallographic tests using SEM (Scanning Electron Microscope).

Key-words:
Friction welding; Parameters; Dissimilar materials; Preheating; Intermetallic compounds