Strength Of Friction Stir Welded Joints Research Articles

Mechanical characterization of friction stir welded dissimilar aluminium alloy using Taguchi approach

Friction stir welding (FSW), a type of solid-state welding, joins two metallic workpieces, whether they are the same or different, by plastically deforming the base metal. The metallic workpieces are heated by the friction between them, which results in plastic deformation and welding. The FSW parameters, however, are what primarily determine the weldability and strength of FSW joints. The research on the FSW parameters and their impact on the quality and weldability of aluminium alloys combined with comparable and dissimilar metals by the FSW method has been previously studied, and this review work highlights that research. The majority of comparable research studies concluded that important factors, such as welding speed, rotational speed, plunge depth, spindle torque, shoulder design, base material, pin profile and tool type have a significant impact on the weldability of the aluminium joint when using the FSW method. Aluminium alloy possesses high wear and corrosion resistance; it has to be used in numerous applications such as automobile field, marine and home appliances due to its low weight. This experimental work planned to weld of dissimilar aluminium alloys such as AA7020 and AA8014 through Friction Stir Welding (FSW) process. Taguchi optimization (L9) is considered for this experimental work to examining of mechanical strength such as tensile strength, tensile strength is conducted by using of Universal testing Machine (UTM). FSW parameters are selected as tool speed (1200 rpm, 1400 rpm and 1600 rpm), welding speed (200 mm/min, 300 mm/min and 400 mm/min) and axial force (4 kN, 6 kN and 8 kN). For the tensile strength analysis, the axial force is highly influenced and the maximum tensile strength of 175 MPa is attained.

The Effect of Friction Stir Welding Parameters on the Weldability of Aluminum Alloys with Similar and Dissimilar Metals: Review

The solid-state welding method known as friction stir welding (FSW) bonds two metallic work parts, whether the same or different, by plastically deforming the base metal. The frictional resistance between both metallic workpieces causes them to produce heat, which produces plastic deformation and welds them. However, the weldability and strength of FSW joints mainly depend on the FSW parameters. This review work highlights the previous research work on the FSW parameters and their effects on the weldability and quality of the aluminum alloys joined with similar and dissimilar metals through the FSW method. About 150 research studies were systematically reviewed, and the articles included data from peer-reviewed journals. It has been concluded that the key parameters, including welding speed, “rotational speed”, “plunge depth”, “spindle torque”, “shoulder design”, “base material”, “pin profile” and “tool type”, significantly affect the weldability of the aluminum joint through the FSW method. Also, the selection of these parameters is important and fundamental as they directly affect the joint. It is recommended that future work focuses on FSW for aluminum. Among these, the most essential is the application of artificial intelligence (AI) techniques to select the optimum FSW parameters for aluminum welding.

Mechanical and Microstructural Characterization of Friction Stir-Welded AA2219: TiCp-Reinforced Composites

Light materials having high strength-to-weight ratio plays a vital role in material science especially in the field of aerospace, marine transportation, military and structural applications. Composite serves the same. Aluminium matrix composite (AMC) is the aluminium matrix which has high strength-to-weight ratio. The purpose of the work is to investigate the mechanical properties of welded AA2219 aluminium alloy reinforced with titanium carbide particles (TiCp). Aluminium matrix is reinforced with TiCp using modified stir casting process. Optical colour graphs, XRD and EDX analysis reveal the presence of TiCp in cast AMC. Tensile test shows the ultimate tensile strength increases with the percentage of TiCp addition. Cut samples of size 100 mm X 50 mm X 6 mm cast AMC were friction stir welded using response surface modelling. Ultimate tensile strength and joint efficiency were calculated for the weld samples, and the effects of input parameters were investigated. Experimental results indicate that tool pin profile has a significant effect on tensile strength of friction stir-welded joints followed by welding speed. It is evident from the response that tool rotational speed had the least effect on ultimate tensile strength. The calculated joint efficiency of the most weld samples was more than 90% with respect to the ultimate tensile strength of the base metal. This work ensures defect free, high efficiency welded joints produced using a wide range of process parameters and recommends parameters for producing best joint tensile properties.

Influence of tool rotation speed on microstructural characteristics and mechanical properties of friction stir welded AA2014-T6 aluminium alloy

Friction stir welding (FSW) is a promising solid-state welding process for precipitation hardening and high strength aluminium alloys. An experimental and theoretical investigation was carried out to check the significance of tool rotation speed on microstructural characteristics and tensile properties of high-strength alloy AA2014. FSW joints were made with varying tool rotation speed from 1,100 rpm to 1,900 rpm with an equal increment of 200 rpm, while the other parameters such as welding speed, shoulder diameter and tool tilt angle were kept constant. The strength of FSW joints was correlated with microhardness, microstructure and fractographs. The joint fabricated with the tool rotation speed of 1,500 rpm, welding speed of 50 mm/min, shoulder diameter of 6 mm and tool tilt angle of 1.5° exhibited superior strength (376 MPa) than the other joints. It could be achieved by the balanced flow of material and defect-free in the stir zone.

Influence of tool rotation speed on microstructural characteristics and mechanical properties of friction stir welded AA2014-T6 aluminium alloy

Friction stir welding (FSW) is a promising solid-state welding process for precipitation hardening and high strength aluminium alloys. An experimental and theoretical investigation was carried out to check the significance of tool rotation speed on microstructural characteristics and tensile properties of high-strength alloy AA2014. FSW joints were made with varying tool rotation speed from 1,100 rpm to 1,900 rpm with an equal increment of 200 rpm, while the other parameters such as welding speed, shoulder diameter and tool tilt angle were kept constant. The strength of FSW joints was correlated with microhardness, microstructure and fractographs. The joint fabricated with the tool rotation speed of 1,500 rpm, welding speed of 50 mm/min, shoulder diameter of 6 mm and tool tilt angle of 1.5° exhibited superior strength (376 MPa) than the other joints. It could be achieved by the balanced flow of material and defect-free in the stir zone.

Fatigue properties of friction stir welded joint of ultrafine-grained 2024 aluminium alloy

Ultrafine-grained (UFG) 2024 aluminium alloy prepared by the equal channel angular pressing was friction stir welded (FSW). The high cycle fatigue and crack growth behaviour of the FSW joint were investigated in air and NaCl solution, respectively. This study demonstrated that FSW was a viable technique for joining UFG materials. The UFG microstructure was retained in the nugget zone (NZ). Compared with the UFG base metal (BM), FSW joint exhibited lower ultimate tensile strength and hardness, and the minimum hardness value was located in the heat affected zone (HAZ). NaCl solution significantly reduced the fatigue strength of FSW joint. Fatigue crack propagation rates in the NZ and HAZ were slower than that in the BM in the whole fatigue life.

Predicting Grain Size and Tensile Strength of Friction Stir Welded Joints of AA7075-T6 Aluminium Alloy

This article reports empirical relationships to predict grain size and tensile strength of friction stir welded (FSW) AA7075-T6 aluminium alloy joints. Six-factor, five-level, central composite rotatable design matrix is used to optimize the experimental conditions. The empirical relationships are developed by response surface methodology (RSM) incorporating tool and process parameters. A linear regression relationship is also established between grain size of weld nugget and tensile strength of FSW joints.