http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
미소원공을 갖는 SF50A재의 피로크랙전파거동에 관한 연구
정재강,김건호,방웅주 조선대학교 생산기술연구소 1994 生産技術硏究 Vol.16 No.2
In this paper, the fatigue crack propagation behaviors are investigated experimentally for the material SF50A forged steel with small circular defects. The summerized results are as follows; 1. The relation between ratio of life N/N_(f) and crack length 2a was straight line aproximately in plot, the material constant m was 0.90-1.66. 2. In the relation to d(2a)/dN and 2a, the unstable propagation region in crack propagation rate appeared at crack initial point. The inclination of these relations in stable region was 1 approximately. 3. The crack propagation rate predition used d(2a)/dN=△K proposed by Paris did not apply because reliability of stress at the more large defect and the high stress was the more large. 4. Mechanical variables proposed by Nisitani, d(2a)/dN = Aσ_(α)^(n)α^(p) was capable of applicaition as a formula to crack propagation rate pγedition because the reliability of stress disappeared.
단조강(SF45A)재의 표면피로크랙 성장 거동에 관한 고찰
金健鎬,정재강,최종로,방웅주 군산대학교 1993 群山水産專門大學 硏究報告 Vol.28 No.1
Fatigue life prediction of fatigue fracture is very important problem. This paper is observed on the surface small crack growth behaviour of smooth specimen. This results were as follows. Surface small crack are created small crack of high density in about 50% of fatigue life, retarded crack growth due to crack coalescence in about 60% and 85%, and when distributed small cracks are growing, it was growthed few large cracks. On the other hand, To analyze crack growth rate used stress intensity factor was difficult due to existed small crack stegnant range.