对超高强钢螺桩的大批量断裂事故进行了断日分析,确认是水介质或БФ—2~(**)胶中的应力腐蚀断裂。测量了几种高强钢在不同热处理条件下的K_(ISCC)和da/dt(平台值)。应用断裂力学对带裂纹螺桩断裂的可能性进行了定量分析, 测量了缺口形成应力腐蚀裂纹的临界应力场强度因子K_(ISCC)。利用不同曲率的缺口试样详细研究了缺口形成应力腐蚀裂纹的规律。由此也可估算无预裂纹的螺桩产生应力腐蚀断裂的力学条件。
The accidental failures of fastening bolt(M33) made of Ultra-high strength steel 3OCrMnSiNi2 were investigated by fraetography. The result showed that it was stress corrosion fracture in water or БФ-2gum. The K_(ISCC) and da/dt of 3OCrMnsiNi2 steel in water and БФ-2 gum were measured by the constant load and constant displacement specimen of L-C and R-C direction. For three low alloy steels, the influence of heat treatment on the K_(ISCC) and da/dt were investigated. The threshold value of stress corrosion cracking of the notch specimen K_(ISCC)(ρ)was measured by modified WOL type notched specimens of various tip radius ρ. The result was as follows where A and B are constants for the speejfje materials. For 3OCrMnSiNi2 (T. S.=158OMPa), the parameters A, B and ρ are 21.7 MPa m~(1/2), 4180 MPa and 0.027 mm respectively. The accidental failures of the fastening bolt with pre-crack or no crack are quantitatively analyzed by linear elastic fracture mechanics. According to these results. preventive measures to avoid failure of the fastening bolt have been suggested.
参考文献
| [1] | |
| [2] | |
| [3] | |
| [4] | |
| [5] | |
| [6] | |
| [7] | |
| [8] |
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