Mechanical and microstructural behavior of industrial spent catalyst waste and boron carbide reinforced aluminum matrix composites

The concept of reuse and recycling has undergone sustained development in industries to prevent the exhaustion of naturally available resources. The current study is about reusing spent catalyst waste from petroleum refining industries as reinforcement in aluminum composite materials. This work utilized the stir casting method to create nano B4C/waste spent catalyst/Al matrix composites by varying the B4C from 0.5 to 2.0 wt% and maintaining the constant 10 wt% of spent catalyst waste, respectively. Furthermore, the impact of nano B4C and spent catalyst waste on the mechanical and microstructure behavior of aluminum matrix hybrid composites were studied. The compressive strength, hardness, and tensile strength of the aluminum composites obtained with different percentages of nano B4C and spent catalyst waste were enhanced significantly. The increase in tensile strength mainly due to the effect of the Orowan strengthening mechanism and thermal stresses caused by the difference in the CTE of aluminum matrix and reinforcement. The effective mechanical behavior was obtained with 1.5 wt% B4C and 10 wt% spent catalyst waste with massive improvements in hardness (65.62%), compressive (31.81%), and tensile strength (48.23%), respectively, compared to base pure aluminum.

Automated summary

The study focuses on the reuse of spent catalyst waste from petroleum refining industries as reinforcement in aluminum composite materials. Nano B4C/waste spent catalyst/Al matrix composites were fabricated using the stir casting method, with varying B4C content (0.5-2.0 wt%) and constant spent catalyst waste content (10 wt%). The addition of nano B4C and spent catalyst waste significantly improved the mechanical properties of the aluminum composites, including compressive strength, hardness, and tensile strength. The enhanced tensile strength was mainly attributed to the Orowan strengthening mechanism and thermal stresses caused by the difference in coefficient of thermal expansion between the aluminum matrix and reinforcement. The most effective mechanical behavior was achieved with 1.5 wt% B4C and 10 wt% spent catalyst waste, resulting in substantial improvements in hardness (65.62%), compressive strength (31.81%), and tensile strength (48.23%) compared to pure aluminum.