Mechanical and microstructure evaluation of novel hybrid TiB₂/B₄C aluminium metal matrix composite

Abstract

In the current study, a novel approach that integrated in situ and ex situ reinforcement techniques was used to develop a hybrid AA7475 aluminium metal matrix composite (MMC). The primary objective of this study was to explore the viability of producing in situ TiB2 particles and adding ex situ B4C particles as reinforcements in the same melt of the aluminium alloy AA7475, with the intention of using these ceramic fillers to improve the mechanical properties of bare AA7475. For in situ particle synthesis, salts such as K2TiF6 and KBF4 were used and for ex situ, B4C particles are utilized. The aluminium MMC was prepared using stir casting method and characterized using ASTM standards. For comparison, composite with only in situ TiB2 particles and composite with only ex situ B4C particles were also fabricated. According to the results, the highest tensile strength of 156.57 MPa was achieved for the hybrid composite made using 5wt% of B4C and TiB2. Similarly, the highest hardness of 144.67 HV was observed for the same. However, the presence of both TiB2 and B4C improved the hardness together. The microstructure shows highly refined phases of the matrix and also the formation of precipitates and reinforcements clearly. The EDAX and XRD confirm the intermetallics formation and dispersion of particles within the matrix material. This aluminium composite with improved properties could be used in automotive, aircraft and in defense sectors where lightweight and high strength materials are required.

Production of AA6061/TiB2/B4C/GNP hybrid surface composites processed by friction stir processing (FSP) and ınvestigation of mechanical properties

“…Bu durum hibrit parçacık ilaveli kompozitlerin mekanik özellikleri iyileştirdiğini göstermektedir. Benzer bir çalışmada Senthilnathan ve Balachandar TiB2-B4C ilaveli Al esaslı tekli ve hibrit kompozit malzemelerde ikili olan (TiB2-B4C) ilavesinin çekme dayanımını iyileştirdiğini rapor etmişlerdir [41]. Essam ve arkadaşları SKY ile ürettikleri grafen nano levha ilaveli yüzey kompozitlerde GNL ilavesinin çekme dayanımını iyileştirdiğini göstermişlerdir [42].…”

Prediction of age-hardening behaviour of LM4 and its composites using artificial neural networks

“…This is continued until peak hardness (formation of fine precipitates) is attained, and after that, because of over-aging, the VHN values drop due to the coarsening of precipitates [32]. In the case of monolithic as-cast composites, the VHN values improved with an increase in reinforcement wt%; the presence of hard reinforcement particles and good bonding between the matrix and reinforcements results in higher VHN values when compared to as-cast LM4 [33]. However, in the case of hybrid composites, samples with higher TiB 2 wt%, i.e., L2T1S, exhibit the highest hardness than L1.5T1.5 S and L2S1T.…”

Experimental investigation of coconut shell charcoal and boron carbide/zirconium dioxide in aluminium 7075 matrix composites under varying operating conditions: a comparative analysis

“…It was procured from Bharat Aerospace Metals, Mumbai, India with the density of 2.52 g/c.c. It is often used in applications that require high abrasion resistance, such as cutting tools, nozzles, and armor plating [23]. It has a very high melting point and is chemically inert (figure 1(a)).…”