차량용재 스프링강의 경량화 및 고강도 제조공법 연구 = A Study on Light Weight and High Strength Manufacturing Methods Spring Steel for the Automobile Material

다국어 초록 (Multilingual Abstract)

The lightness of components required in automobile and machinery industry is requiring high strength of components. so this requirement is accomplished as the process of shot-peening method that the compressive residual stress is made on the metal surface. Special research is therefore needed about compressive residual stress on the metal surface in the process of shot-peening method. therefore, in this paper the effect of compressive residual stress of spring steel(JISG SUP-9) by shot-peening on fatigue crack growth characteristics in environment condition(temperature) and mechanical condition(shot velocity, stress ratio)was investigated with considering fracture mechanics. by using the methods mentioned above, the following conclusions have been draw.
(I) The fatigue crack growth rate(da/dN) of the Shot-peened material was lower than that of the Un-peened material. And in high temperature, fatigue crack growth rate decreases with increasing temperature. while fatigue crack growth rate increases by decreasing temperature in low temperature.
(2) Fatigue life shows more improvement in the Shot-peened material than in the Un-peened material. And compressive residual stress of surface on the Shot-peen processed operate resistance force of fatigue crack propagation.

목차 (Table of Contents)

• Abstract
• 1. 서론
• 2. 시험편 및 실험방법
• 3. 실험 결과 및 고찰
• 4. 결론
• 참고 문헌