• 제목/요약/키워드: 쇼트

검색결과 236건 처리시간 0.025초

차량용 중공 스테빌라이저바의 내측 쇼트피닝 효과 (Effect of Inner Shot Peening Process for Tubular Stabilizer Bars)

  • 서유원;서진원;이원기;김진영
    • 대한기계학회논문집A
    • /
    • 제41권11호
    • /
    • pp.1119-1124
    • /
    • 2017
  • 차량 하부에 장착된 스테빌라이저바는 차량이 곡선 구간을 선회할 때 차량의 자체를 유지해 줌으로서 차량 주행을 보다 편안하게 해 준다. 스테빌라이저바는 중실과 중공 타입 2가지가 있으며, 차량의 경량화를 위해 중공 형태의 스테빌라이저바의 적용이 늘고 있다. 차량의 경량화를 위한 중공 스테빌라이저바는 중실에 비해 무게가 34% 이상 경량화가 가능하지만 경량화 비율이 높아질수록 제품의 내구 수명은 급격하게 감소하는 경향을 나타낸다. 이러한 내구 수명 감소에 대한 대책으로서 소재의 고강도 및 고경도 소재를 적용하거나 쇼트피닝 공법을 개선 하는 등의 노력을 통해 내구 수명을 보장할 수 있다.

회로 시뮬레이션을 위한 유기물 쇼트기 다이오드 모델링 (Modeling of Organic Schottky Diodes for Circuit Simulations)

  • 김효종;냠바야르 바타르;김시호
    • 대한전자공학회논문지SD
    • /
    • 제47권6호
    • /
    • pp.7-12
    • /
    • 2010
  • 유기물 쇼트기 다이오드 회로 설계시에 사용가능한 소자의 모델을 구현하였다. AHDL을 이용하여 상용 CAD 환경으로 보편적으로 사용되는 Spectre의 설계환경에서 측정 결과를 입력 파라미터로 반영하여 회로 시뮬레이션을 할 수 있는 환경을 구성하였다. 유기물 RFID의 구현에 필수적인 정류회로를 제작하여 회로의 주파수 특성을 측정하였으며, AHDL 모델을 사용한 시뮬레이션 결과와 비교하였다. 제작된 정류회로의 주파수 특성은 13.56MHz의 RFID 동작을 만족시키기에는 부족하지만, 135kHz 주파수 대역 RFID에서는 동작이 가능하다.

쇼트피닝 잔류응력 예측을 위한 유한요소해석 (Finite Element Analysis for Prediction of Residual Stresses Induced by Shot Peening)

  • 김철;양원호;성기득;고명훈
    • 한국자동차공학회논문집
    • /
    • 제9권1호
    • /
    • pp.198-204
    • /
    • 2001
  • The shot peening is largely used for a surface treatment of metallic components where small spherical pellets called shots are blasted onto the surface with velocities up to 100 m/s. This treatment leads to improvement of fatigue behavior due to the developed compressive residual stresses, and so it has gained widespread acceptance I the automobile and aerospace industries. The residual stress profile on surface layer depends on the parameters of shot peening, which are, shot velocity, shot diameter, coverage, impact angle, material properties etc. and the method to confirm this profile is the measurement by X-ray diffractometer only. Despite the importance to automobile ad aerospace industries, little attention has been devoted to the accurate modelling of the process. In this paper, the simulation technique is applied to predict the magnitude ad distribution of the residual stress and plastic deformation caused by shot peening with the help of the finite element analysis.

  • PDF

쇼트피이닝 가공된 스프링강의 저온 피로균열진전 평가 (A Study on the Shot Peening on the Low Temperature Fatigue Crack Propagation)

  • 박경동;정찬기;하경준;박상오;손명군;노영석
    • 한국해양공학회:학술대회논문집
    • /
    • 한국해양공학회 2001년도 추계학술대회 논문집
    • /
    • pp.282-286
    • /
    • 2001
  • In this study, CT specimens were prepared from spring steel(SUP9) processed shot peening which was room temperature, low temperature and high temperature experiment. And we got the following characteristics from fatigue crack growth test carried out in the environment of room, low temperature and high temperature at $25^{\circ}C$,$-30^{\circ}C$,$-50^{\circ}C$,$-70^{\circ}C$ and $-100^{\circ}C$ in the range of stress ratio of 0.05 by means of opening mode displacement. The threshold stress intensity factor range $\Delta K_{th}$ in the early stage of fatigue crack growth (Region I ) and stress intensity factor range $\Delta K$ in the stable of fatigue crack growth (Region II) was decreased in proportion to descend temperature. It assumed that the fatigue resistance characteristics and fracture strength at low temperature and high temperature is considerable higher than that of room temperature in the early stage and stable of fatigue crack growth region.

  • PDF

쇼트피닝 가공을 통한 스프링강의 부식거동에 관한 연구 (A Study on Corrosive Behavior of Spring Steel by Shot-Peening Process)

  • 안재필;박경동
    • 대한기계학회:학술대회논문집
    • /
    • 대한기계학회 2004년도 추계학술대회
    • /
    • pp.325-330
    • /
    • 2004
  • Recently, the request for the high strength of material is more and more increased in the area of industrial environment and machinery. To accomplish the high strength of materials, carbonizing treatment, nitrifying treatment, shot-peening method are representatively applied, however, shot-peening method is generally used among the surface processes. Shot peening is a cold working process used to impact Compressive residual stressed in the exposed surface layers. Benefits due to shot peening are increase in resistance to fatigue, stress corrosion cracking, fretting, galling, erosion and closing of pores. In this study, the influence of shot peening on the corrosion was investigated on spring steel immersed in 3.5% NaCl. The immersion test as performed on the two kinds of specimens. Corrsion potential, polarization curve, residual stress and etc, were investigated from experiment results. From test result the effect of shot peening on the corrosion was evaluated. The important results of the experimental study on the effects of shot peened on the environment corrosion of spring steels are as follows; In case of corrosion potential, shot peened specimen shows more activated negative direction as compared with parent mental. Surface of specimen, which is treated with the shot peened is placed as more activated state against inner base metal. It can cause t도 anti-corrosion effect on the base metal.

  • PDF

JISG4081SUP7-DIN50CrV4강의 피로강도에 미치는 쇼트피이닝의 영향 (Effect of Shot Peening on Fatigue Strength of JISG4081SUP7-DIN50CrV4 Steel)

  • 박경동;정찬기
    • 한국해양공학회지
    • /
    • 제15권4호
    • /
    • pp.66-72
    • /
    • 2001
  • Recently the steel parts used at automobiles are required to be used under high stress more than ever before in need of the weight down. To achieve this requirement of a high strength steel, it must be necessary to decrease inclusion content and surface defect as like decarburization, surface roughness etc.. In this study, the surface conditions are measured to know the influence on fatigue properties by two cases of shot peening of two-stage shot peening and single-stage shot peening. And for this study, two kinds of spring steel (JISG4081SUP7, DIN 50CrV4) are used. This study shows the outstanding improvement of fatigue properties at the case of two-stage shot peening in the rotary bending fatigue test and this is assumed to be from on low stress condition, the 1st stage shot peening is not affected by nonmetallic inclusion under metal. it is possible that the 2nd stage shot peening increases the fatigue life and the high stress but that is affected by nonmetallic inclusion under metal. so far beeasily DIN50CrV4 have made high stress. But, results also show fatigue failures originated at inclusion near surface, and this inclusion type is turned out to be a alumina of high hardness.

  • PDF