Influence of SiC Nanoparticle Reinforcement on FSS Welded 6061-T6 Aluminum Alloy

Abstract

The current research focuses on the mechanical properties and the microstructural behavior of friction stir spot-welded 6061-T6 aluminum alloy reinforced with SiC nanoparticles. Weld samples are produced with and without the addition of SiC nanoparticles to the joint. The microhardness and lap shear strength of the joints are investigated. The cross section of welds and the fracture surfaces are studied by a stereo zoom microscope. Microstructure and distribution of reinforced particles in the stir zone are examined through optical and scanning electron microscopies. It is observed that the reinforcement of SiC nanoparticles significantly influences the grain size and hence the weld properties. The highest hardness of 93 HV and the maximum shear load of 2650.5 N are observed at the stir zone of the sample with 29% SiC. All the weld samples exhibit the similar “W” shape hardness profile. From the observed results, the selected set of process parameters is found adequate in order to fabricate sound Al/SiC composite joints.

Experimental Review on Friction Stir Welding of Aluminium Alloys with Nanoparticles

“…Studies also showed the amount of incorporating the nanoparticles have a greater influence on the mechanical properties of the joint. For instance, a study showed that, increased volume fraction of SiC nanoparticles in AA6061 alloy improved the hardness profile and tensile strength, which is shown in Figure 12 [72]. This improvement was mainly due to the absence of interface gap between the base metal and weld nugget.…”

“…In addition to the type of reinforcing nanoparticle, the volume of nanoparticle addition also aids in grain size formation [31,71]. For instance, FSW of AA6061 (i.e., alloy similar to AA6082 alloy) with SiC nanoparticles showed that increased volume fraction of nanoparticle reinforcement (from 14% to 29%) led to homogeneous dispersion, causing reduction in grain size as well as improvement in the mechanical properties [72].…”

“…This reduction in tensile and hardness properties could be due to the association of SiC nanoparticles with intermetallic compounds and the annealing region under high rotational speed and slow traverse speed [70,73]. The FSW joints with and without reinforcement nanoparticles fractured at the HAZ region, which could be due to low hardness and softening effect [67,69,72]. However, the joint reinforced with TiC nanoparticles showed better hardness when compared to the joints without reinforcement and joints with SiC nanoparticle reinforcement [40,69].…”

Compression after Impact Behaviour and Failure Analysis of Nanosilica-Toughened Thin Epoxy/GFRP Composite Laminates

“…To achieve a homogeneous dispersion of nanofillers in the matrix, it is inevitable to use an expensive surface functionalization process [22,23,24]. Dispersion behavior of nanofillers in the matrix can be investigated through various techniques like Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and atomic force microscopy (AFM) [25,26].…”

Effects of SiC and Al2O3 Reinforcement of Varied Volume Fractions on Mechanical and Micro Structure Properties of Interlock FSW Dissimilar Joints AA7075-T6-AA7475-T7

“…The other joints (1%, 3%, 4%, 5% with Al 2 O 3 and 1%, 3%, 4%, 5% with SiC) depicts slightly lower UTS values due to the reduced or increased quantity of wt% of the reinforcements, particularly when the wt% of the SiC is increased beyond 3% the shrinkage happens on the surface of the weld thus leading to decrease in strength of the joints [18]. Therefore, the morphology of the evenly distributed SiC particulates in Stir zone has greater impact on the bonding of interlock joints slightly higher than Al 2 O 3 , as shown in Fig.…”