Impact of Tool Pin Geometry and Optimized Process Parameters on Mechanical Properties of Friction Stir Welded AZ80A Mg Alloy

Abstract

In this paper, the influence of optimized FSW process parameters namely tool rotational speed, feed rate, mechanical axial force and impact of tool pin geometry on the mechanical properties of AZ80A Mg alloy are experimentally investigated in a detailed manner. M35 grade High Speed Steel (HSS) tool with three different pin geometries namely straight cylindrical, threaded cylindrical and taper cylindrical was employed in this investigation. The joints obtained under these conditions are subjected to tensile tests as per ASTM (American Society for Testing and Materials) B557M – 10 standards and tensile fracture surfaces are examined using optical and Scanning Electron Microscope (SEM). The investigations proved that defect free sound joints with better mechanical properties are produced by taper cylindrical tool pin geometry under optimized process parameter values. It was experimentally found that the optimized FSW process parameter values namely 1.0 mm/min feed rate, 5 kN axial force, 1000 rpm of tool rotational speed along with a taper cylindrical pin profiled tool is preferable for FSW of AZ80A Mg alloy of 5mm thickness.Moreover, this experimental work revealed us that the taper cylindrical pin profiled tool fabricated sound, defect free welded joints along with better & improved mechanical properties when compared with other two pin profiles.

Experimental Identification of Optimized Process Parameters for FSW of AZ91C Mg Alloy Using Quadratic Regression Models

“…Another critical task in producing sound quality joint for any welding technique is directly related to the employment of ideal and optimal input parameters [24] and [25]. The specimens welded under different combinations of process parameters derived using the conventional techniques require an inspection to decide whether they meet the expected standards or not.…”

Experimental investigation on the improvement of the properties of the AZ80A Mg alloy joints using friction stir welding process

“…Even though the wider application of Mg alloys is dependent on feasible welding techniques, there is still a lack of suitable, effective & efficient joining techniques for majority of the Mg alloys [21][22][23][24]. Properties & features of Mg alloys like their strong cracking susceptibility, large energy requirement makes them difficult to be joined using the conventional welding techniques in an effective manner [25,26]. In the recent years, Friction stir welding (FSW), an energy efficient & eco-friendly solid state joining method, with the ability for fabricating joints without melting the base materials, has gained the attraction of various experimental researchers working with the objective of joining light weight metals including Mg alloys [27][28][29].…”