Establishment of X-Ray Fractography as Failure Analysis Method

X射线断口分析失效分析方法的建立

• 批准号: 61302035
• 负责人: TANAKA Keisuke
• 金额: $ 4.03万
• 依托单位: Kyoto University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Co-operative Research (A)
• 财政年份: 1986
• 资助国家: 日本
• 起止时间: 1986 至 1987
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-61302035/
• 关键词: X-ray diffraction; Fracture surface analysis; Residual stress; Full width at half maximum; Brittle fracture; Fatigue; Stress corrosion cracking; 事故破面; 疲労; 高温破面

1. X-ray diffraction observation of fracture surfaces yields useful information to analyze the causes of failure accidents of engineering structures. This experimental technique has been maned X-ray fractography. The following four X-ray parameters have been confirmed useful for determing the mode and mechanical conditions of fracture: residual stress, full width at half maximum (FWHM), diffraction pattern, and transformed phase.2. Computer image processing of diffraction patterns was use to determined the reversed yeild zone within the maximum yield zone on the fatigue fracture surface of mild steel. The distribution of FWHM is also useful for this determination of two kinds of zone.3. Although the residual stresses measured on fracture surfaces were tension in most cases, the compressive residual stresses were detected on the fatigue fracture under a high compressive mean stress and on the shear fracture surface made under mixed mode loading.4. The X-ray fractographic methods established for fatigue fracture in air at room temperature were found to be applicable to corrosion fatigue and high temperature fatigue. Quantitative analysis of creep fracture surface is left for a future study.5. The measured distribution of residual stresses beneath the fracture surface of alumina was usable for determining the depth of the plastic zone.6. The depth of the plastic zone beneath fracture surfaces measurd by X-ray methods is expressed by a fracture mechanics equation of the stress intensity factor and the material yield strength.7. X-ray fractographic techniques were successfully applied to fracture accidents in service of shaft, pin, bearing and high temperature materials.

1. 断裂面x射线衍射观察为分析工程结构破坏事故的原因提供了有用的信息。这种实验技术被称为x射线断口学。以下四个x射线参数已被证实可用于确定断裂的模式和力学条件：残余应力，半最大全宽度（FWHM），衍射图和相变相。利用衍射图的计算机图像处理，确定了低碳钢疲劳断口最大屈服区内的反向屈服区。FWHM的分布对这两种带的确定也很有用。虽然在断口表面测得的残余应力大多为拉应力，但在高平均压应力下的疲劳断口和混合模式加载下的剪切断口上测得的残余应力为压应力。建立的室温空气疲劳断口x射线断口分析方法适用于腐蚀疲劳和高温疲劳。蠕变断口的定量分析有待进一步研究。测量的氧化铝断口下残余应力分布可用于确定塑性区的深度。用x射线法测得的断裂面下塑性区深度由应力强度因子与材料屈服强度的断裂力学方程表示。x射线断口技术已成功应用于轴、销、轴承和高温材料的断裂事故中。

项目成果

Keiji Ogura: "A Simplified X-Ray Analysis of Fractured Surface by Using Sub-Surface Information" Journal of the Society of Materials Science, Japan. 36. 799-804 (1987)

Keiji Ogura：“使用次表面信息对断裂表面进行简化的 X 射线分析”日本材料科学学会杂志。

Yasuo Yoshioka: "X-Ray Analysis on the Fatigue Fracture Surface of Stainless Steels" Hihakaikensa. 35. 524-531 (1986)

Yasuo Yoshioka：“不锈钢疲劳断裂表面的 X 射线分析”Hihakaikensa。

広瀬幸雄: 日本材料学会第23回X線材料強度に関する討論会講演論文集. 23. 76-81 (1986)

Yukio Hirose：日本材料学会第 23 届 X 射线材料强度研讨会论文集，23. 76-81 (1986)。

林真琴: 日本材料学会第23回X線材料強度に関する討論会講演論文集. 23. 91-100 (1986)

Makoto Hayashi：日本材料学会第 23 届 X 射线材料强度研讨会论文集，23. 91-100 (1986)。

Keisuke tanaka: Role of Fracture Mechanics in Modern Technology. 735-746 (1987)

Keisuke tanaka：断裂力学在现代技术中的作用。