作者: S.G. Shabestari , R. Gholizadeh
DOI: 10.4028/WWW.SCIENTIFIC.NET/AMR.445.289
关键词: Materials science 、 Precipitation (chemistry) 、 Microstructure 、 Optical microscope 、 Intermetallic 、 Metallurgy 、 Thermal analysis 、 Scanning electron microscope 、 Alloy 、 Ultimate tensile strength 、 General Engineering
摘要: Dense precipitation of various intermetallic compounds is a common feature in the microstructure of Al-Si piston alloys. In this investigation, microstructure of LM13 alloy and three high Cu-containing Al-Si piston alloys with different amounts of Ni, Fe, and Mn were studied by means of optical microscopy (OM) and scanning electron microscopy (SEM). Chemical composition of the phases was determined by using energy dispersive X-ray analysis (EDX). The precipitation of the phases was studied through thermal analysis of the solidifying samples. Also, tensile properties and hardness of the samples were measured. The results showed that the various intermetallics such as Al12(FeMn)3Si2, Al3Ni, Al9FeNi, and Al3CuNi precipitated during the solidification. The high Cu-containing alloy with optimum levels of Ni (1.8 wt.%), Fe (0.75 wt.%), and Mn (0.3 wt.%) has the highest tensile strength (250 MPa) and hardness (110 BHN) among the other alloys.