Issue 74

N. S. Dhongade et alii, Fracture and Structural integrity, 74 (2025) 1-19; DOI: 10.3221/IGF-ESIS.74.01

every 10 minutes 5 times using a graphite rod to attain homogeneity and reduce the possibility of agglomeration. The synthesis of AA7075/TiB 2 /ZrO 2 composite using in-situ casting is illustrated in Fig. 1. Hexachloroethane (C 2 Cl 6 ) was added for the degasification process, which removes the trapped air from the melt and enhances the properties of the composite.

Figure 1: Schematic representation of Hybrid AMC utilizing situ casting.

Zn

Mg

Cu

Fe

Cr

Si

Mn

Ti

Ni

Al

5.60

2.60

1.60

0.30

0.25

0.30

0.20

0.20

0.02

Bal

Table 1: AA7075 chemical composition (wt.%).

Zirconia paste was applied to the mold. Zircon’s low wettability allows high precision casting with a good surface finish. It also prevents the melt from sticking to the die and avoids metal penetration into the mold. The melt was poured using the crucible tongs into the pre-heated iron mold and allowed to solidify. Pre-heating of the mold is required for the uniform distribution of the molten melt. After the fabrication, the hybrid composite was subjected to different machining processes to prepare specimens for various testing. Specimens were prepared for microstructural studies, hardness tests, tensile tests, and wear tests according to ASTM standards. It is schematically shown in Figs. 2 and 3.

Dimensions of microstucture studies sample

Wear test sample dimensions

Figure 2: Casted Hybrid MMC with Schematic illustration for specimen.

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