“…The hardness of the SZ can be ascribed to the grain refinement and distribution of Al 2 O 3 mp resulting in pinning effect. 53 Smaller grain size exhibits higher hardness as per Hall–Petch relationship. 54–56 Figure 11.Micro-hardness profile of composite Joints, (a) at 700rpm, (b) at 900 rpm, (c) 1100 rpm.…”
Section: Resultsmentioning
confidence: 99%
“…The hardness of the SZ can be ascribed to the grain refinement and distribution of Al 2 O 3 mp resulting in pinning effect. 53 Smaller grain size exhibits higher hardness as per Hall-Petch relationship. [54][55][56] The micro-hardness of the composite joints embedded with reinforcement particles also enhanced due to the presence of hard Al 2 O 3 particles.…”
Section: Influence Of Al 2 O 3 Mp On Tensile Strengthmentioning
In the present study, the fabrication of dissimilar composite joints of AA6061/AA7075 incorporated with micro-sized Al2O3 particles was carried out using friction stir welding. The impact of the dispersion pattern of different volume fractions of Al2O3 micro-particles (Al2O3mp) under various combinations of tool rotational speed (RS) and traverse speed (TS) on the weld quality was studied. The composite joints were tested for tensile strength, micro-hardness, wear, and microstructural development. The results demonstrated that higher grain refinement due to dynamic recrystallization (DRX) and pinning effect of Al2O3mp considerably improved the weld quality. Higher improvements in the mechanical properties of the composite joints were also observed as the volume fraction of Al2O3mp increased. Consequently, the composite joint processed at RS of 1100 rpm, TS of 40 mm/min with 10% volume fraction of Al2O3mp exhibits the higher tensile strength of 241.35 MPa with joint efficiency of 83.80% and maximum micro-hardness of 157.5 HV. In comparison with base materials, the incorporation of Al2O3mp also improved the wear resistance of the composite joints.
“…The hardness of the SZ can be ascribed to the grain refinement and distribution of Al 2 O 3 mp resulting in pinning effect. 53 Smaller grain size exhibits higher hardness as per Hall–Petch relationship. 54–56 Figure 11.Micro-hardness profile of composite Joints, (a) at 700rpm, (b) at 900 rpm, (c) 1100 rpm.…”
Section: Resultsmentioning
confidence: 99%
“…The hardness of the SZ can be ascribed to the grain refinement and distribution of Al 2 O 3 mp resulting in pinning effect. 53 Smaller grain size exhibits higher hardness as per Hall-Petch relationship. [54][55][56] The micro-hardness of the composite joints embedded with reinforcement particles also enhanced due to the presence of hard Al 2 O 3 particles.…”
Section: Influence Of Al 2 O 3 Mp On Tensile Strengthmentioning
In the present study, the fabrication of dissimilar composite joints of AA6061/AA7075 incorporated with micro-sized Al2O3 particles was carried out using friction stir welding. The impact of the dispersion pattern of different volume fractions of Al2O3 micro-particles (Al2O3mp) under various combinations of tool rotational speed (RS) and traverse speed (TS) on the weld quality was studied. The composite joints were tested for tensile strength, micro-hardness, wear, and microstructural development. The results demonstrated that higher grain refinement due to dynamic recrystallization (DRX) and pinning effect of Al2O3mp considerably improved the weld quality. Higher improvements in the mechanical properties of the composite joints were also observed as the volume fraction of Al2O3mp increased. Consequently, the composite joint processed at RS of 1100 rpm, TS of 40 mm/min with 10% volume fraction of Al2O3mp exhibits the higher tensile strength of 241.35 MPa with joint efficiency of 83.80% and maximum micro-hardness of 157.5 HV. In comparison with base materials, the incorporation of Al2O3mp also improved the wear resistance of the composite joints.
“…In other words, surface roughness decreased with increasing the pass numbers. The agglomeration and insufficient mixing of nanoparticles in the base metal and matrix have produced rougher surface and waviness in all types of the surface of AA6061 hybrid nanocomposites with one pass 43 . In addition, with the multi-pass number, the surface roughness and waviness decreased due to asperities formation and the nanoparticle fragmentation in the base metal.…”
To fundamentally investigate the influence of different friction stir processing (FSP) strategies, namely raster, spiral, and parallel in various passes on the surface integrity of hybrid aluminum nanocomposites reinforced by titanium oxide (TiO2), silicon carbide (SiC), and zirconium oxide (ZrO2) nanoparticles, various examinations were conducted. The surface integrity, comprising microstructural characterization, elemental composition, surface topography, roughness, waviness, and microhardness was studied by different analyses, including scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), optical microscopy (OM), atomic force microscopy (AFM), and Vickers microhardness machine in different zones. Results demonstrated that surface integrity and quality are dependent on the type of FSP strategy. SEM images revealed that a homogeneous distribution of the nanoparticles in the matrix is obtainable by the parallel and raster FSP strategies. Roughness and waviness measurements illustrated that the surface topography of the hybrid nanocomposite was symmetrical and improved by raster strategy and TiO2 + ZrO2 nanoparticle reinforcement. Furthermore, the two-pass FSP improved the arithmetic average surface value (Ra) such that the Ra of two passes decreased by 32.5% compared to a single one. The mean microhardness in the spiral, raster, and parallel pass strategies increased by ~ 45%, 37%, and 31%, respectively.
“…The most common typical characteristic features like surface appearance and flash formation, shape and size of the nugget zone, onion ring-like pattern, banded structure formation, and the various defects (most common voids, cavities, tunnel, and pinholes) are visually examined at different magnifications (low or high) [59,66,[78][79][80][81]. The conditions like the addition of reinforcement particles, workpiece material property (including thickness, type, temperature, and thermal conductivity), process parameters range, and tool geometries are the most important that play a major role in the origin of all the above-mentioned features [53,54,[82][83][84][85].…”
Section: Macrostructure Of Mmr Butt Jointsmentioning
Fusion welding processes do not find attention due to their restriction to use for certain grades of materials and alloys. Friction Stir welding (FSW) or the solid-state joining process has proven to be a more efficient process for the welding of metal-matrix reinforced composite butt joints by employing various combinations of reinforcement particles and base matrices compared to the fusion welding process. Due to the solid-state nature of the FSW process, no melting of base material would occur which leads to no toxic fumes, low energy consumption, environmentally friendly, and ease of operation that makes FSW a more versatile welding process for aerospace, automobile, and transportation industries. However, the challenges in joining metal matrix reinforced composites remain even with a substantial advancement in the process made during current years. This review article outlines a brief overview of the state of art of metal matrix reinforced welds joined using FSW. More emphasis with critical evaluation has been done on the (a) macrostructural and microstructural characteristics of a metal matrix reinforced welds which merely depend on the plasticized material flow and reinforcement particles behavior and its difficulty for uniform distribution of reinforcement particles in the weld zone based on the combination of reinforcement particles and the metal matrix materials, (b) assessment of mechanical properties of the metal matrix reinforced welds those are directly interdependent on the selection of process parameters by which the grain refinement and their reinforcement particles distribution depend that leads to changes in such properties, and (c) fracture and wear properties of the metal matrix reinforced welds which again depends on the reinforcement particles and the metal matrix materials combination. The conclusions of this review are ended up with recommendations for the directions for future research.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
