Influence of the Coupling between the Mechanical Characteristics and the Welding Conditions by the FSSW Process: Case of the Bimaterial Alu-Steel

Benattou Bouchouicha,H Mekri,H Christophe,A Miloudi,A Imad

doi:10.3221/igf-esis.46.07

Abstract

The present study investigates the effect of joining parameters on the mechanical characteristics of dissimilar friction stir spot welding (FSSW) between AA 6061 Al and galvanized steel. Mechanical performance has been evaluated by shear and microhardnes testing. A macrostructural examination has revealed the creation of mechanical interlocking in the Al steel connections. Shear failure load has increased with increasing both tool rotational speed and plunge depth for all FSSW connections. Higher plunge depth has improved the mechanical interlocking between lower and upper sheet due to the formation of a larger secondary flash.

Highlights

The increasing demand for energy saving as well as environmental issues in different industry sectors has led to the necessity of using lightweight alloys and advanced high strength steels
The assembly between two different materials (Al/Steel, Al/Cu,...) by conventional technologies of welding by fusion is rather complicated and can be due completely difficult to their various physical and chemical properties, in particular with the difference in the cast iron temperatures and with mutual solubility. These processes have the disadvantage of severe heating and cooling cycles which can result in the formation of brittle cast structure, porosity and large amounts of intermetallic phases (FenAlm) that have a detrimental effect on the mechanical properties of the joint, multiaxial fatigue, fatigue properties and fracture mechanism of load [16, 17, 29, 30]
C ommercial grade AA 6061 alloy and galvanized steel sheets of 1.7mm thick were used as the starting materials

Summary

Introduction

The increasing demand for energy saving as well as environmental issues in different industry sectors has led to the necessity of using lightweight alloys and advanced high strength steels. The assembly between two different materials (Al/Steel, Al/Cu,...) by conventional technologies of welding by fusion is rather complicated and can be due completely difficult to their various physical and chemical properties, in particular with the difference in the cast iron temperatures and with mutual solubility These processes have the disadvantage of severe heating and cooling cycles which can result in the formation of brittle cast structure, porosity and large amounts of intermetallic phases (FenAlm) that have a detrimental effect on the mechanical properties of the joint, multiaxial fatigue, fatigue properties and fracture mechanism of load [16, 17, 29, 30].

Methods

Results

Conclusion