Local binary pattern for the evaluation of surface quality of dissimilar Friction Stir Welded Ultrafine Grained 1050 and 6061-T6 Aluminium Alloys

Akshansh Mishra

doi:10.14201/adcaij2020926977

Abstract

Friction Stir Welding process is an advanced solid-state joining process which finds application in various industries like automobiles, manufacturing, aerospace and railway firms. Input parameters like tool rotational speed, welding speed, axial force and tilt angle govern the quality of Friction Stir Welded joint. Improper selection of these parameters further leads to fabrication of the joint of bad quality resulting groove edges, flash formation and various other surface defects. In the present work, a texture based analytic machine learning algorithm known as Local Binary Pattern (LBP) is used for the extraction of texture features of the Friction Stir Welded joints which are welded at a different rotational speed. It was observed that LBP algorithm can accurately detect any irregularities present on the surface of Friction Stir Welded joint.

Highlights

Friction Stir Welding is a solid state joining process which was developed by The Welding Institute (TWI) mainly for joining the light-weight materials like aluminium and magnesium alloys [1,2,3]
Akshansh Mishra Local binary pattern for the evaluation of surface quality of dissimilar Friction Stir Welded Ultrafine Grained 1050 and 6061-T6 Aluminium Alloys speed of 400 mm/min, Fig. 6b shows the joint obtained at the tool rotational speed of 800 rpm and tool traverse speed of 600 mm/min, Fig. 6c shows the joint obtained at the tool rotational speed of 800 rpm and tool traverse speed of 800 mm/min, Fig. 6d shows the joint obtained at the tool rotational speed of 800 rpm and tool traverse speed of 1000 mm/min
Various surface defects like flash formation, groovy edges and lack of contact present in Friction Stir Welded joints can be detected by implementing Local Binary Patterns

Summary

Introduction

Friction Stir Welding is a solid state joining process which was developed by The Welding Institute (TWI) mainly for joining the light-weight materials like aluminium and magnesium alloys [1,2,3]. Friction Stir Welding process results high quality welds but the welding performance mainly depends on the proper selection of various input parameters like pin temperature, tool rotational speed, feed rate, welding speed, temperature distribution, rotating tool torque, applied downward forging force on tool shoulder etc. The working mechanism of the Friction Stir Welding process is shown in the Fig. 2. The main beauty of the Friction Stir Welding process is that it uses non-consumable metallic tool which is harder than the base material to be joined [4]. Due to the rotation of the rotating tool there is a generation of friction between the work piece and the rotating tool which results in plastic deformation the work piece as shown in the Fig. 3c)

Methods

Results

Conclusion