Study on Real-Time Weld Quality Evaluation by Acoustic Emission for Production of Drills by Friction Weldiing

J. Ocean Eng. Technol. 1993;7(2):121-130.

마찰용접에 의한 드릴 생산에서의 AE에 의한 실시간 품질평가에 관한 연구

오세규,윤인진,오정환,오명석

부산수산대학교 기계공학과,부산직업훈련원 기계과,부산수산대학교 기계공학과,부산공업대학 금형과

Keywords: friction Welding, Optimization, Real-Time Weld Strength Evaluation, Acoustic Emission Technique, Quantitative Relationship, Joint Efficiency

핵심용어: 마찰용접, 최적화, 용접강도실시간평가, 음향방출법, 정량상관성, 이음효율

Abstract

A study off riction welding of high speed steel(SKH 51) bar for blade side to carbon steel(STC 3)bar for shank side was carried out experimentally through tensile test, hardness test, microstructure, and acoustic emission (AE) test. So, this paper deals with optimizing the welding conditions and the real-time quality (strength) evaluation of friction weleded joints by acoustic emission technique. The results obtained are summarized as follows: (1) For friction welded joints of SKH 51to STC 3 steel bars, the total upset (U) increases linearly with an increase of heating time (t sub(1)). (2) The determined optimum welding conditions are heating time (t sub(1)) 7-9 sec, upsetting time (t sub(2)) 5 sec, heating pressure(P sub(1)) 12 kg sub(f)mm supper(2), upsetting pressure (P sub(2)) 15 kg sub(f) mm supper(2) and rotating speed (n) 2, 000 rpm, resulting in a computed relationship between the tensile strength of the joint .sigma. (kg sub(f) mm supper(2)) and the heating time t sub(1) (sec) as the following. sigma.=2.39t sub(1)