Transactions of Materials Processing (소성∙가공)

The Korean Society for Technology of Plasticity and materials processing (한국소성∙가공학회)
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The Effect of Drawing and Heat Treatment on Fatigue Life and Machinability in Free Machining Steel

쾌삭강의 피로수명 및 절삭성에 미치는 인발-열처리의 영향

  • 서창희 (대구기계부품연구원 기계부품소재시험평가센터) ;
  • 김동배 (대구기계부품연구원 기계부품소재시험평가센터) ;
  • 오상균 (대구기계부품연구원 기계부품소재시험평가센터) ;
  • 정윤철 (대구기계부품연구원) ;
  • 박명규 (영남이공대 기계과) ;
  • 김영석 (경북대학교 기계공학부)
  • Received : 2009.11.16
  • Accepted : 2009.01.25
  • Published : 2010.04.01
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Abstract

Drawing and normalizing are efficient means for controlling strength, fatigue and machinability of free machining steel. Normally strength and machinability are conflicting properties which need to be optimized. In this study, the effects of normalizing temperature and reduction of area on strength, fatigue and machinability were investigated. Fine grains were generated at lower normalizing temperature and fatigue life was increased with decreasing grain size. Matrix was work hardened and elongated with increasing reduction of area. Inclusions also were elongated and cross-sectional area of inclusions along drawing axis was decreased. The effects of work hardening and grain size on fatigue life were significant, but only work hardening affected machinability. Shape and distribution of inclusions after drawing had little effect on fatigue life and machinability.

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References

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