[논문]SCM440H 금형강의 표면 처리에 따른 피로 특성 연구

염현호; 이문구; 이춘만; 전용호

doi:10.7736/kspe.2013.30.8.779

Abstract ▼ AI-Helper

Increased efficiency and improved performance associated with light-weight materials were investigated in this study. Numerous studies have investigated surface treatments to improve the fatigue strength of metals. Laser heat treatment is a promising method because the power and spot size can be eas...

Increased efficiency and improved performance associated with light-weight materials were investigated in this study. Numerous studies have investigated surface treatments to improve the fatigue strength of metals. Laser heat treatment is a promising method because the power and spot size can be easily controlled, allowing a small heat affected zone (HAZ). However, changes in the material properties can result; in particular, the material can become more brittle. In this study, a combination of laser heat treatment and vibration peening was proposed to increase fatigue strength without changing the material characteristics. SCM440H was investigated experimentally, and specimens were tested using a giga-cycle ultrasonic fatigue tester. The results show that the combination of these two processes significantly increased the fatigue strength and, furthermore, different fracture types were observed after a small and large number of cycles.

주제어

AI 본문요약
AI-Helper

* AI 자동 식별 결과로 적합하지 않은 문장이 있을 수 있으니, 이용에 유의하시기 바랍니다.

가설 설정

2. The process combination can achieve significant high fracture strength even the laser heat treatment temperature is not reaching the transformation temperature. In other words, this process combination can increase the fatigue life without losing its ductility.
3. The S/N curve slope is decreased when the peening process is applied. This happens because the surface notches and grains get smaller by the external mechanical energy.
4. The fracture strength increased ~10 and ~25% by the process combination. The untreated specimen fractured 2.

제안 방법

Different process condition is given for each of specimen. No treatment, 600℃ laser heat treatment only, peening only, and 600 ℃ laser heat treatment and peening specimens were made and examined the fatigue strength. All the specimens were fractured at ~305MPa but the number of cycle was completely different.
The experiments will be made with untreated, peening only, and different heat treatment temperatures which are under or over the transformation temperature, about 750 ℃ in steel and peening cases.
The SCM440H is chosen because it is commonly used in the die or mold industry and structural parts of engine or transmission in automotive industry. The test specimens are prepared with combination of two processes, laser heat treatment and vibration peening. Both processes selected because they can control the process conditions easily.
To investigate the effect of those combinations, the fatigue tests were performed with ultrasonic fatigue tester (UFT) at a frequency of 20kHz, stress ratio of R=-1 and displacement range is ~20 ㎛ at room temperature. The benefit for UFT is expediting the experiments.

대상 데이터

2 shows the laser heat treatment system. The laser is 1kW diode laser (Laserline, LDM-1000-100). Recently, the diode laser generally uses for the heat treatment because it can offer various beam shapes and relatively good absorptivity in steels.
1 shows the specimen which used in this study. The specimen is a circular tapered hourglass-shaped with 4mm of minimum diameter, 14.5mm of notch radius, and 76.53mm of total length. The specimen is specially designed to make a resonance in the ultrasonic fatigue tester.

성능/효과

The main finding about this study is that the process combination can increase the fatigue strength without changing the material’s own mechanical properties.
6. The results show that the fatigue strength of untreated specimen can stand 6.66 x 10⁷ cycles at 232.59 MPa. The peening only specimen can stand 7.

후속연구

Before examine the effect of combination of laser heat treatment and peening process on fatigue strength, a preliminary study is performed to find out whether the process combination is beneficial. Fig.
proposed that the over peening can increase the surface micro cracks and reduce the fatigue life. For this reason further studies will be required regarding the reasons why process combination is beneficial, the process conditions optimization, fracture mechanism on the giga cycle, and effect on microstructural changes and residual stresses on surfaces by the processes.
This means that the process combination can be applicable to the case which is not allowed losing its ductility. Further study will be made to investigate why this happened by examine the microstructures.

참고문헌 (5)

Kennedy, E., Byrne, G., and Collins, D. N., "A review of the Use of High Power Diode Lasers in Surface Hardening," Journal of Materials Processing Technology, Vol. 155-156, pp. 1855-1860, 2004.

상세보기
Yasuoka, M., Wang, P., Zhang, K., Qiu, Z., Kusaka, K., Pyoun, Y. S., and Murakami, R., "Improvement of the Fatigue Strength of SUS304 Austenite Stainless Steel Using Ultrasonic Nanocrystal Surface Modification," Surface & Coatings Technology, Vol. 218, pp. 93-98, 2013.

상세보기
Suh, C. M., Pyoun, Y. S., Cho, I. H., and Baek, E. B., "UNSM Surface Technology for Manufacturing and Remanufacturing Torsion Bars for Crawler Vehicles," Journal of Ocean Engineering and Technology, Vol. 25, No. 6, pp. 80-85, 2011.
Cho, I. S., Shin, C. S., Kim, J. Y., and Jeon, Y. H., "Accelerated Ultrasonic Fatigue Testing Applications and Research Trends," Trans. Korean Soc. Mech. Eng. A., Vol. 36, No. 6, pp. 707-712, 2012.

원문보기 상세보기
Na, G. D., Yoo, Y. T., Shin, H. J., and Shin, B. H., "Characteristics Induction and Laser Surface hardening of SM45C Steel," J. Korean Soc. Precis. Eng., Vol. 23, No. 7, pp. 39-50, 2006.

내보내기 구분	파일저장 인쇄 메일전송
구성항목	기본정보 상세정보 관리번호, 논문명, 저널/프로시딩명, 저자 , 발행년, 권, 호, 시작페이지, 끝페이지, 발행기관 관리번호, 논문명, 대등논문명, 저자 , 저널/프로시딩명, 발행기관, 발행년, 발행언어, 권, 호, 시작페이지, 끝페이지, ISBN, ISSN, 주제분야, 키워드, 초록(한글), 초록(영문), 저자(소속기관)
저장형식	Text(ASCII format) Excel format RefWorks Direct Export RIS format (for Reference Manager, ProCite, EndNote), Scholar's Aids, Mendeley
메일정보	받는사람 (필수) @ 보내는사람 (선택) @ 제목 내용 KISTI 검색결과 이메일 서비스
안내	총 건의 자료가 검색되었습니다. 다운받으실 자료의 인덱스를 입력하세요. (1-10,000) 검색결과의 순서대로 최대 10,000건 까지 다운로드가 가능합니다. 데이타가 많을 경우 속도가 느려질 수 있습니다.(최대 2~3분 소요) 다운로드 파일은 UTF-8 형태로 저장됩니다. 파일의 내용이 제대로 보이지 않을실 때는 웹브라우저 상단의 보기 -> 인코딩 -> 자동선택 여부를 확인하십시오. ~ Text(ASCII format) Excel format

연합인증

[국내논문] SCM440H 금형강의 표면 처리에 따른 피로 특성 연구
Effect of Surface Treatment on Fatigue Strength of SCM440H 원문보기

Abstract ▼ AI-Helper

주제어

AI 본문요약
AI-Helper

가설 설정

제안 방법

대상 데이터

성능/효과

후속연구

참고문헌 (5)

이 논문을 인용한 문헌

저자의 다른 논문 :

관련 콘텐츠

원문 보기

원문 URL 링크

이 논문과 함께 이용한 콘텐츠

AI-Helper ※ AI-Helper는 오픈소스 모델을 사용합니다.

선택된 텍스트

연합인증

[국내논문] SCM440H 금형강의 표면 처리에 따른 피로 특성 연구 Effect of Surface Treatment on Fatigue Strength of SCM440H 원문보기

Abstract ▼ AI-Helper

주제어

AI 본문요약 엑셀 다운로드 AI-Helper

가설 설정

제안 방법

대상 데이터

성능/효과

후속연구

참고문헌 (5)

이 논문을 인용한 문헌

저자의 다른 논문 :

염현호 (1) 이문구 (17) 이춘만 (148) 전용호 (14)

관련 콘텐츠

원문 보기

원문 URL 링크

이 논문과 함께 이용한 콘텐츠

AI-Helper ※ AI-Helper는 오픈소스 모델을 사용합니다.

선택된 텍스트

[국내논문] SCM440H 금형강의 표면 처리에 따른 피로 특성 연구
Effect of Surface Treatment on Fatigue Strength of SCM440H 원문보기

AI 본문요약
AI-Helper