Exploring the mechanical behaviour and microstructure of AA7075/B₄C/ZrN hybrid composite fabricated through powder metallurgy techniques

The matrix and the reinforcement both are the lifelines of a composite, and their inherent properties are very significant in determining their applicability toward various industrial applications, due to the fact that it directly impacts the strength, durability, and performance of the material under different service conditions. This paper presents the mechanical as well as microstructural behavior of AA7075/B₄C/ZrN hybrid composites fabricated by using the powder metallurgy technique. The dispersion of the reinforcement plays a very vital role in the activation of the load-sharing mechanism. Apart from enhancing mechanical properties, porosity reduction in composites is indispensable in design and processing optimization. Due to the addition of ZrN in the AA7075/B₄C composite, XRD analysis showed that the Al₃Zr compound was formed, which contributed to the improved mechanical properties of the composite up to some point. The maximum compression strength of approximately 185 MPa was achieved at the composite with 2 wt% ZrN and 8 wt% B₄C, while the maximum hardness of 113 HV occurred at 3 wt% ZrN and 8 wt% B₄C. Higher contents of ZrN and B₄C further above created an impact for extra pores along with high scale intermetallic compounds, which, near to destroy the strength of the composite, eventually formed voids and weak interfaces. It is these very results that prove the optimized AA7075/B₄C/ZrN composite, with its better mechanical properties and controlled porosity, to be quite fit for high-strength aerospace and automotive applications in which durability and performance are pertinent.