The Analysis of Microstructure and Mechanical Properties in B4C Reinforced Al–Zn Alloy Matrix Composites Manufactured Using a New Sintering Approach

The present study aims to propose a new and non-complex sintering method in powder metallurgy in order to manufacture a light material with high mechanical properties. The proposed new sintering method is based on the principle that compaction is applied to a heated sample following classical sintering method. In this way, microstructure and mechanical properties of new samples manufactured using the proposed post sintering compaction method were compared with the samples manufactured using classical sintering method. In this context, in order to find the most optimal Al–Zn alloy ratio, different weight percentages of Zn (5–15–25–35–45%) were added to Al. When the manufactured alloys with classical sintering and post sintering compaction methods were compared, the most optimal alloy ratio was observed to be 15% Zn (Al–15Zn) manufactured using post sintering compaction method. In the next step, the matrix alloy with the most optimal ratio was reinforced with B₄C in different weight percentages (1–2–3%) to manufacture Al matrix composites using post sintering compaction method. The microstructure analysis of the manufactured samples demonstrated that reinforcement particles were generally located at the grain boundaries and these particles caused the presence of porosities around them. In addition, mechanical test results indicated that increasing reinforcement ratio affected mechanical properties negatively. It can be thus concluded that a composite material with 1% B₄C reinforcement ratio was superior to matrix alloy (Al–15Zn) in terms of microstructure, density, absorbed energy, hardness and compressive strength, and thus it is a critical reinforcement ratio in improving material properties.