Work

Effects of Zr Additive on Microstructure, Mechanical Properties, and Fractography of Al-Si Alloy

Year: 2018

Type: article

Abstract: The effects of Zr additive on the microstructure, mechanical properties, and fracture behavior of Al-Si alloy were systematically investigated. The additive of Zr obviously reduced the size of Si particles and changed its morphology. Grain size refinement was promoted by the reaction between Al and Zr forming Al3Zr and ZrSi2 compounds. Compared to a Zr-free alloy, the additive enhanced the tensile strength, compressive strength, shear strength, and hardness. The optimized Zr content was 2.4 wt % corresponding to a tensile strength of 231.1 MPa, compressive strength of 343.1 MPa, shear strength of 174.9 MPa, and hardness of 85.5 HV, greater than those of the Zr-free alloy. This illustrates that fine-grain strengthening and the existence of a second phase can improve the mechanical properties of Al-Si alloy. The fracture surface of Al-Si alloy without Zr additive showed a brittle fracture mode and there were no pits on the fractured surface. In the presence of Zr addictive, a typical plastic deformation with a large amount of pits was evidenced.

Source: Metals

DOI: 10.3390/met8020124

Authors: Hui Qian, Degui Zhu, Chunfeng Hu, Xiaosong Jiang

Institution: Southwest Jiaotong University

Language: English

Topic: Aluminum Alloy Microstructure Properties

Subfield: Aerospace Engineering

Field: Engineering

Domain: Physical Sciences

Open Access status: gold

Estimated APC paid: $3,137

Funders: Southwest Jiaotong University, Recruitment Program of Global Experts, Fundamental Research Funds for the Central Universities