The Effect of Premixed Al-Cu Powder on the Stir Zone in Friction Stir Welding of AA3003-H18

Abstract

In this research, 3-mm-thick AA3003-H18 non-heat-treatable aluminum alloy plates were joined by friction stir welding (FSW). It was performed by adding pure Cu and premixed Cu-Al powders at various rotational speeds of 800, 1000, and 1200 rpm and constant traveling speeds of 100 mm/min. At first, the powder was filled into the gap (0.2 or 0.4 mm) between two aluminum alloy plates, and then the FSW process was performed in two passes. The microstructure, mechanical properties, and formation of intermetallic compounds were investigated in both cases of using pure Cu and premixed Al-Cu powders. The results of using pure Cu and premixed Al-Cu powders were compared in the stir zone at various rotational speeds. The copper particle distribution and formation of Al-Cu intermetallic compounds (Al 2 Cu and AlCu) in the stir zone were desirable using premixed Al-Cu powder into the gap. The hardness values were significantly increased by formation of Al-Cu intermetallic compounds in the stir zone and it was uniform throughout the stir zone when premixed Al-Cu powder was used. Also, longitudinal tensile strength from the stir zone was higher when premixed Al-Cu powder was used instead of pure Cu powder.

Friction Stir Welding of Non-Heat Treatable Al Alloys: Challenges and Improvements Opportunities

“…The additions of various reinforcement particles have been introduced as an improvement strategy for increasing the mechanical properties of FSWed joints of strain-hardened Al alloys. For instance, the effects of TiC [162], TiO 2 [163], and SiC [164] nanoparticles, Cu and pre-mixed Cu-Al Powder [56,165], Al 3 Sc compound [166], and inserting Cu foils [167] on the mechanical properties of FSWed joints of Al alloys have been previously investigated. All of these studies have unanimously reported that the incorporation of reinforcement particles into the gap between two sheets strengthens the stir zone's mechanical properties, provided that appropriate welding parameters are chosen.…”

“…Rotational and traverse speeds, the number of FSW passes, and the direction of the multi-passes are the most common variables that have been studied on FSW nonheat-treatable Al alloys with the addition of reinforcement particles. Subsequently, the significant effects of these parameters on mechanical properties (hardness, tensile strength, and fatigue) have been well documented [56,162,165,168].…”

“…According to the literature, the variation in reinforcement particles' size and shape are observed by changing the introduced welding parameters in the weld zone. When the rotational speed increases and traverse speed decreases, not only is a uniform distribution of particles achieved, but also reinforcement particles become finer [56,165,168].…”

Effect of process parameters on friction stir welding of aluminium alloy AA6082–T6 with an interlayer using response surface methodology

“…Several researchers [7][8][9][10][11][12][13] have conducted experimental studies to predict the effect of interlayers on the mechanical properties of FSW joints. Interlayers of Zinc (Zn), Copper (Cu), Brass, Aluminium, Silicon carbide (SiC), Titanium Carbide (TiC) etc, are used to improve the mechanical properties of FSW joints.…”

“…The joints fabricated using a 10 μm thickness of Zn interlayer possessed a higher tensile strength than the FSW joint produced with different Zn interlayers. Abnar et al [9,10] used pure Cu and a mixture Al-Cu particles as interlayers in FSW of AA3003 aluminium alloy. In this experimental study, the interlayer particles are first fused into the gap of abutting plates using friction stir processing, and the FSW process is performed afterwards.…”