不同Fe/Ni比的Al-Si活塞合金中耐热相的析出及强化效果

Evolution and Strengthening Effects of the Heat-Resistant Phases in Al-Si Piston Alloys with Different Fe/Ni Ratios.

作者信息

Meng Fanchao, Wu Yuying, Hu Kaiqi, Li Yang, Sun Qianqian, Liu Xiangfa

机构信息

Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials, Ministry of Education, Shandong University, Jinan 250061, China.

Shandong Al & Mg Melt Technology Company Limited, Jinan 250061, China.

出版信息

Materials (Basel). 2019 Aug 7;12(16):2506. doi: 10.3390/ma12162506.

DOI:10.3390/ma12162506

PMID:31394748

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC6719983/

Abstract

The evolution of three major heat-resistant phases (δ-AlCuNi, γ-AlCuNi, T-AlFeNi) and its strengthening effects at high temperature in Al-Si piston alloys with various Fe/Ni ratios were studied using field emission scanning electron microscope (FE-SEM), electron probe microanalysis (EPMA), and X-ray diffraction (XRD). With the increase of Fe/Ni ratios, the heat-resistant phases begin to evolve in category, morphology, and distribution. The results show that a suitable Fe/Ni ratio will cause the T-AlFeNi phase to appear and form a closed or semi-closed network with δ-AlCuNi and γ-AlCuNi phases instead of the originally isolated heat-resistant phases. As a result, the ultimate tensile strength of the optimized alloy reached 106 MPa with a Fe/Ni ratio of 0.23, which was 23.3% higher than that of base alloy at 350 °C, which is attributed to the fact that a closed or semi-closed network microstructure is advantageous to the bearing of mechanical loads. This work may provide useful ideas for the development of high temperature resistant piston alloys.

摘要

利用场发射扫描电子显微镜（FE-SEM）、电子探针微分析（EPMA）和X射线衍射（XRD）研究了不同Fe/Ni比的Al-Si活塞合金中三个主要耐热相（δ-AlCuNi、γ-AlCuNi、T-AlFeNi）的析出及高温强化效果。随着Fe/Ni比的增加，耐热相在种类、形态和分布上开始发生演变。结果表明，合适的Fe/Ni比会促使T-AlFeNi相出现，并与δ-AlCuNi和γ-AlCuNi相形成封闭或半封闭网络，而不是原来孤立的耐热相。结果，优化合金在Fe/Ni比为0.23时的抗拉强度达到106 MPa，在350℃下比基体合金高23.3%，这归因于封闭或半封闭网络微观结构有利于承受机械载荷。这项工作可为耐高温活塞合金的开发提供有益思路。