한국기계기술학회지 (Journal of the Korean Society of Mechanical Technology)

  • 제13권2호
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  • Pages.93-100
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  • 2011
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  • 1229-604X(pISSN)
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  • 2508-3805(eISSN)
한국기계기술학회 (Korean Society of Mechanical Technology)
권호 표지

음향방출법에 의한 SM45C 고주파 열처리 강의 기계적 특성 평가

The Analysis of Mechanical Properties of the High Frequency Induction Hardening SM45C Steel by Acoustic Emission

  • 이장규 (송도테크노파크 자동차기술부품센터)
  • 투고 : 2011.05.13
  • 심사 : 2011.06.22
  • 발행 : 2011.06.30
⟨ 이전 논문 다음 논문 ⟩

초록

This study deals with the high frequency induction hardening (HF at $850^{\circ}C$, 120kHz & 50kW condition) SM45C steel. (1) The HF specimen, which was tempered at $150^{\circ}C$, did not show any tempering effect. A brittle fracture occurred at rounded area of the tensile specimen. AE (acoustic emission) amplitude distribution showed between 45dB and 60dB. (2) A slip and fracture occurred at the hole area of the HF specimen which was tempered at $300^{\circ}C$. As they pass the yield point, the AE energy is increased intermittently and AE amplitude distribution exists between 70dB and 85dB. In addition, after imposing the maximum tensile load, AE signals showed high amplitude and energy distribution. The AE amplitude showed between 45dB and 70dB. (3) A brittle fracture occurred at HF specimen which was tempered at $450^{\circ}C$ as if it is torn in the direction of $45^{\circ}$ on parallel area over the both sides of the tensile specimen, which lead to several peak appeared in AE energy. It was found that the AE amplitude was relatively low and the AE energy was high.

키워드

참고문헌

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