Korean Institute of Surface Engineering

pISSN : 1225-8024 | eISSN : 3399-8403


공학

한국표면공학회지 (43권5호 230-237)

Surface Modification of AC4A Aluminum Alloy Castings Using Friction Thermomechanical Process

마찰열기계적 공정을 이용한 AC4A 합금의 표면개질

윤태욱;고영봉;고병천;박경채;
Yoon, Tae-Wook;Ko, Young-Bong;Ko, Byung-Chun;Park, Kyeung-Chae;

평화오일씰공업(주);한국화학융합시험연구원;경북대학교 금속신소재공학과;
Pyung Hwa Oil-seal Industry Co., Ltd.;Korea Testing & Research Institute;Materials Science and Metallurgical Engineering of Kyungpook National University;

DOI : 10.5695/JKISE.2010.43.5.230

Abstract

FTMP(friction thermo-mechanical process) is an adaptation of friction stir welding, and can be used as a generic process to modify the microstructure at selective locations. In this study, in order to analyze characteristics of surface modification of ACA4 castings by FTMP, change of rotating speed(R/S) and traveling speed(T/S) of tool were applied as conditional parameter. Analysis of microstructure, hardness, surface roughness and depth of modified zone(MZ) were searched. The best condition were obtained at R/S 600 rpm and T/S 100 mm/min. At this time, hardness was 82 HV, the surface roughness was 0.07 mm and the depth at MZ was 1.72 mm. Free defects microstructure and fine Si particles formation and strong forging effects were analyzed at MZ.

Keywords

Friction Thermo-mechanical Process(FTMP);Surface modification;AC4A aluminum alloy castings;Modified zone;Si particle size;Hardness distribution;