中南大学学报(英文版)
Journal of Central South University
| Vol. 27 No. 6 June 2020 |
（1. Shaanxi Key Laboratory of Photoelectric Functional Materials and Devices, School of Materials and Chemical Engineering, Xi’an Technological University, Xi’an 710021, China;
2. China North Engine Research Institute (Tianjin), Tianjin 300400, China）
Abstract:In the present work, samples of Al-Si-Cu piston alloy after T6 heat treatment were exposed for 2 h at temperatures ranging from 400 to 550 °C. The evolution of surface roughness and microstructure of the alloy during thermal exposure was studied by combination methods of roughness profiles, optical and scanning electron microscopy as well as XRD analysis. It is found that the roughness and mass of the alloy increase with the raise of the thermal exposure temperature, and the increasing rates of them are slow as the exposure temperature is below 500 °C, but accelerates abruptly when the temperature is higher than 500 °C. The variation of surface roughness of the alloy is closely related to phase transformation and oxidation during the thermal exposure.
Key words: surface roughness; thermal exposure; Al-Si-Cu piston alloy; microstructure; oxidation
