Quality Enhancement of TIG Welded Al6061 SiCp Composites by Age Hardening Process

The current work focuses on enhancing wear resistance due to the presence of reinforcements and the effect of ageing treatment on hybrid composites of Al6061-SiC+B4C. By varying weight percentage, two kinds of reinforcements, viz. silicon carbide and boron carbide, were prepared for hybrid composites by the liquid state process known as the method of stir casting. The solutionising temperature of 550 °C for 2 hours and ageing temperature of 100-200°C at different time intervals were used for both Al6061 alloy and its composites during heat treatment. Microstructural and mechanical characterisation were carried out using a standard testing procedure. Compared to Al6061 matrix alloy, artificially peak aged composites show 100-140% improvement in hardness due to harder reinforcements and precipitation of solute rich secondary phases during ageing treatment. Overall, an 80-100% increase in wear resistance observed during peak ageing of hybrid composites. Analysis of Al6061 matrix alloy wear out surface shows extensive grooving and ploughing of the surface with the matrix material smear at many spots. The presence of tribolayer in Al6061-SiC+B4C composites shows a smoother surface than the Al6061 matrix alloy, which results in an excellent lubrication effect during an improvement in wear resistance. The wear surface of base aluminium alloy doesn’t show the existence of iron in the tribolayer. The research work is significant in forming a thermally activated wear-resistant metallic tribolayer with good tribological properties.

Section: Effect Of Reinforcement and Ageing Temperature On Hardness Propertiesmentioning

confidence: 99%

Tribolayer Behaviour and Wear of Artificially Aged Al6061 Hybrid Composites

Shettar

Hiremath

Shankar

et al. 2021

“…The dislocation density in hybrid composites depends on the size of the used reinforcements [12]. Though in the current work, the sizes of both particles, SiC and B4C, were the same (35~ 40 µm), the density difference between B4C (2.52 g/cm 3 ) and SiC (3.1 g/cm 3 ) led to higher volume fraction of B4C particles causing smaller interparticle distance in the matrix and accordingly higher dislocation density than SiC particles [12]. The precipitation of secondary solute rich phases during age hardening in 3B3S was confirmed through SEM studies taken up for specimens aged at 100°C which emerged as the most suitable temperature for optimal peak aging behaviour.…”

Section: Aging Curve and Hardnessmentioning

confidence: 58%

“…Aluminium-magnesium-silicon alloys (Al-Mg-Si; also known as 6xxx series) are moderate strength, heat-treatable alloys with excellent formability and resistance to corrosion. The Al6061 alloy has been studied extensively due to its technological significance and a further increase in the strength is obtained by precipitation (age) hardening [3]. Aluminium metal matrix composites (AMMCs) reinforced with ceramic particles, viz., SiC, B4C, Al2O3, TiC have received considerable attention due to their high specific strength and modulus, low coefficient of thermal expansion and good resistance to wear [4].…”

Section: Introductionmentioning

confidence: 99%

Aging Kinetics and Microstructural Features of Al6061-SiC+B4C Stir Cast Hybrid Composites

Sathyashankarasharma

Gurumurthy

Shankar

et al. 2019

The purpose of the current metallurgical work is to analyse the mechanical property alteration and microstructure evaluation of Al6061 hybrid composites by age hardening treatment using three different aging temperatures. Al6061 hybrid composites reinforced with B4C and SiC particles have been manufactured using two-stage stir casting method. The optical micrographs were analysed for the dispersivity of the reinforcements in the matrix. To assure the type of reinforcements in the matrix SEM analysis was carried out. It was found thatduring solutionising and aging at 100, 150 and 200°C, presence of SiC and B4C particles in the hybrid Al6061 matrix composites showed substantial improvement in hardness compared to that of the base alloy. Transmission electron microscopy (TEM) was used to identify the intermetallic phases, morphology and orientation of the particulates responsible for the peak aging behaviour. It was observed that while aging at 100°C excellent peak hardness values are observed in the composite group with well-distributed fine precipitates of Mg2Si along grain boundaries as well as within the grains. The composition Al6061-3B3S composites showed an additional secondary intermetallic phase viz., α-Al12Fe3SiMg along with Mg2Si, which is responsible for the superior aging behaviour over other compositions.

“…Gas tungsten arc welding (GTAW) or tungsten inert gas (TIG) Welding have been widely used in the manufacturing industry, such as the automobile industry and other transportation industry [1][2]. TIG welding is commonly used when precision and high quality are required [3]. The research and development related to TIG welding improve the welding process's effectiveness and performance and improve the energy efficiency in recent years is vital because of the global warming issue [4].…”

Section: Introductionmentioning

confidence: 99%

Study of Cross-Combination and Square-Combination Configuration Magnetic Field on Tungsten Inert Gas Welding

Baskoro¹,

Amat²,

Arisoni³

2021

In this study, cross-combination and square-combination configuration of the permanent external magnet were used in tungsten inert gas welding process. The external magnetic field effect to the arc plasma was observed using two cameras from the front view and side view. The depth of penetration and weld profile was investigated after welding. In this study, two types of magnets were employed; a 3 mm magnet with intensity ranging from 270-280 mT and a 5 mm magnet with 400-415 mT. Each configuration has three sub-configurations: forward, backward, and side, so there were 12 parameters in this study. The result shows that a cross-combination 5 mm magnet can increase weld penetration in any position, forward, backward or side deflection, and improve the depth-to-width ratio, however using 3 mm magnet did not influence the penetration significantly. Cross-combination has more stiffness and stability of the arc than square-combination. Most configurations have the same size weld bead width. Square combinations had fluctuated result, stiffness and stability of the arc was poor. This investigation aims to enlarge our understanding of the magnetic field effect on the arc plasma and the weld profile. In future, the arc blow effect from the external magnetic field can be controlled and regulated to improve TIG welding performance.