The present work is aimed to explore the microstructural and mechanical characteristics of coal-fly ash reinforced iron metal-matrix composites (IMMCs), synthesized through powder metallurgy technique. Coal-fly ash wt%, compacting load and sintering temperature were considered as the input variables, whereas sintered density and microhardness of the composites were taken as the output responses. Flowability and compressibility of the starting materials were demonstrated using Hausner ratio and Carr’s index. Decorous morphological, crystallographic and elemental characteristics of the starting materials and IMMCs were deliberated using Scanning electron microscopy, X-ray diffraction and Energy-dispersive X-ray spectroscopy investigations respectively. A significant improvement in the microhardness of IMMCs by 50% and drop in density by 35% were found at 15 wt% as compared to 0 wt% reinforcement. The substantial increase in the microhardness eventually resulted in an increase in their specific microhardness by a factor of two. Significant improvements in the microhardness of IMMCs at 15 wt % of reinforcement, compacted at 10 ton and sintered at 1150°C were found to be prompted by the strengthening mechanisms like load transfer, Hall–Petch effect and Taylor strengthening. The analytically calculated microhardness in the light of strengthening mechanisms was found smaller than the corresponding experimental values as a function of wt % of reinforcement. Further, statistical analysis of the obtained results was carried out using response surface methodology.

本工作旨在探讨通过粉末冶金技术合成的粉煤灰增强的铁金属基复合材料（IMMC）的微观结构和力学性能。粉煤灰的重量％，压实载荷和烧结温度作为输入变量，而复合材料的烧结密度和显微硬度作为输出响应。使用Hausner比和Carr指数证明了原料的流动性和可压缩性。分别使用扫描电子显微镜，X射线衍射和能量色散X射线光谱学研究了原料和IMMC的装饰形态，晶体学和元素特征。与0 wt％的增强相比，在15 wt％的情况下，IMMC的显微硬度显着提高了50％，密度下降了35％。显微硬度的显着提高最终导致其比显微硬度提高了两倍。研究发现，载荷转移，霍尔—帕奇效应和泰勒强化等强化机制促进了IMMC在15 wt％的增强强度，10 ton的压实强度和1150°C的烧结温度下的显微硬度显着提高。发现根据增强机理的分析计算的显微硬度小于对应的实验值，其是增强体重量％的函数。此外，使用响应面方法对获得的结果进行统计分析。