Microstructural heterogeneity enabled balance of room- and high-temperature properties in high-volume intermetallics reinforced aluminum alloys

Incorporating high-volume-fraction intermetallics into aluminum alloys is a typical way to enhance both room- and high-temperature strength, yet often sacrifices ductility. In this study, a novel Al–Si–Fe–Ni–Mn alloy with 35.6 vol.% and multi-scale heterogeneous IMCs was fabricated via powder metallurgy and thermo-mechanical processing. The alloy achieves an exceptional balance of room-temperature strength (477 MPa), ductility (8.2%) and high-temperature strength (277 MPa at 300°C), demonstrating remarkable strength-ductility synergy and superior heat resistance. This arises from a hierarchical architecture that coordinates deformation across multiple size scales. The findings presented herein provide fresh perspectives for the design of high-performance aluminum alloys.
A high-volume-fraction, multi-scale IMCs-strengthened aluminum alloy with a heterogeneous microstructure is designed and investigated, achieving significantly enhanced room-temperature and high-temperature (exceeding 300°C) mechanical properties.

将高体积分数金属间化合物（intermetallics）掺入铝合金中，是同时提升室温与高温强度的典型手段，但该方法往往会牺牲材料塑性。本研究采用粉末冶金结合热机械加工工艺，制备出一种含35.6%体积分数多尺度异质金属间化合物（intermetallic compounds，简称IMCs）的新型Al-Si-Fe-Ni-Mn铝合金。该合金实现了室温强度（477 MPa）、塑性（8.2%）与300℃下高温强度（277 MPa）的优异平衡，展现出显著的强塑性协同效应与优异的耐热性能，其机制源于一种可协调多尺度变形的分级结构。本文所提出的研究结果为高性能铝合金的设计提供了全新视角。
本研究设计并研究了一种高体积分数、多尺度金属间化合物（IMCs）强化且具备异质微观结构的铝合金，其室温与高温（超过300℃）力学性能得到显著提升。