This study explores the investigation of enhanced mechanical and thermal properties of Mg/B4C/Cr hybrid composites having varying 3, 5, 7 wt. % of B₄C and Cr reinforcements in Mg-matrix. The bottom pouring vacuum-based squeezed stir casting process is used to fabricate these composites. The Mg/B₄C/Cr hybrid composites evaluate ultimate strength, elongation percentage, expansion coefficient, heat conductivity, hardness, and then compared with Mg/5B₄C and Mg/5Cr composites. Each of Mg-based hybrid composites results indicates higher thermal conductivity and expansion coefficient than Mg/5B₄C and Mg/5Cr composites. The tensile results reveal that the Mg/B₄C/Cr hybrid composites show mixed morphologic behaviour of brittle-ductile while Mg/5B₄C and Mg/5Cr composites are individually evident with brittle behaviour. The proper interfaces between Cr particles and Mg matrix illustrate reduced dislocations with efficient strength and thermal results. However, B₄C particles present in the base matrix is liable for the effective hardness and ultimate strength in the Mg/B₄C/Cr hybrid composites. In comparison with other composites (Mg/B₄C and Mg/Cr), Mg/B₄C/Cr hybrid composite shows efficient thermal conductivity with high thermal conductance which diverges towards the application of gas cylindrical liners.

中文翻译：

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Mg/B4C/Cr混合复合材料力学和热学研究的实验研究

本研究探索了具有不同 3、5、7 重量比的 Mg/B4C/Cr 混合复合材料的增强机械和热性能的研究。Mg 基体中 B ₄ C 和 Cr 增强材料的百分比。底部浇注真空挤压搅拌铸造工艺用于制造这些复合材料。Mg/B ₄ C/Cr 混合复合材料评估了极限强度、伸长率、膨胀系数、热导率、硬度，然后与 Mg/5B ₄ C 和 Mg/5Cr 复合材料进行了比较。每种镁基混合复合材料的结果表明，其热导率和膨胀系数均高于 Mg/5B ₄ C 和 Mg/5Cr 复合材料。拉伸结果表明 Mg/B ₄C/Cr 杂化复合材料表现出脆-韧混合形态行为，而 Mg/5B ₄ C 和 Mg/5Cr 复合材料分别具有明显的脆性行为。Cr 颗粒和 Mg 基体之间的适当界面表明位错减少，具有有效的强度和热结果。然而，基体中存在的B ₄ C 颗粒对 Mg/B ₄ C/Cr 混合复合材料的有效硬度和极限强度有影响。与其他复合材料（Mg/B ₄ C 和 Mg/Cr）相比，Mg/B ₄ C/Cr 混合复合材料显示出高效的热导率和高热导率，这在气体圆柱衬里的应用上有所不同。