权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Development of high precision evaluation system of fatigue damage by time-of-flight neutron method

飞行时间中子法高精度疲劳损伤评估系统研制

基本信息

批准号：
16360051
负责人：
AKINIWA Yoshiaki
金额：
$ 8.51万
依托单位：
Nagoya University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
2004
资助国家：
日本
起止时间：
2004 至 2006
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-16360051/
关键词：
Neutron Phase stress TOF Angle dispersive method Fatigue damage Profile broadening

项目摘要

(1) The diffraction elastic constants for calculating the stress from the strain were determined for several structural materials on the basis of the diffraction intensity. The accuracy of the stress measurement was clarified.(2) Stress measurement in the smooth specimens of aluminum alloy reinforced with SiC particles under monotonic axial loading was carried out. In the composites, the phase stress in the constituent phase was measured. The diffraction plane and diffraction intensity for stress measurement were determined on the basis of the confident limit. Fatigue damage could be determined from the change of the profile broadening.(3) Fatigue tests of an austenitic stainless steel SUS316NG were conducted under axial tension compression. The change of the profile broadening was measured during fatigue process. When the large compressive residual stress was induced by the machining, the compressive residual stress decreased in the early stage at the higher applied stress amplitude. On the other hand, for the lower stress amplitude, the change of the residual stress is small.(4) For the stress measurement of the welded components, the second kind of stress is important to determine the macro stress. In that case, the use of the small piece as a reference of the stress free lattice spacing is effective. The residual stress in the butt welded joint could be determined.(5) The line broadening in the ultrafine-grained Cu fabricated by ECAP method increased with the plastic strain. The value, however, decreased to the initial value during unloading. The change of the line broadening under fatigue loading is not so large.(6) Performance evaluation of the radial collimator to limit the gage volume of lmm was conducted. The measured profile was identical to the result of the simulation. The stress can be measured with enough accuracy.

(1)根据衍射强度确定了几种结构材料的衍射弹性常数，用于从应变计算应力。阐明了应力测量的准确性。(2)对SiC颗粒增强铝合金光滑试件在单调轴向载荷作用下的应力进行了测量。在复合材料中，测量了组成相中的相应力。根据置信限确定了应力测量的衍射面和衍射强度。疲劳损伤可以从轮廓展宽的变化来确定。(3)对奥氏体不锈钢SUS316NG进行了轴向拉压疲劳试验。测量了疲劳过程中轮廓展宽的变化。当切削加工产生较大的残余压应力时，在较高的施加应力幅下，残余压应力在加工初期有所降低。另一方面，对于较低的应力幅值，残余应力的变化较小。(4)在焊接构件的应力测量中，第二类应力是确定宏观应力的重要因素。在这种情况下，使用小片作为无应力网格间距的参考是有效的。利用该方法可以确定焊接接头的残余应力。(5)ECAP法制备的超细晶Cu中的谱线展宽随塑性应变的增加而增大。然而，该值在卸载期间降低到初始值。在疲劳载荷作用下，谱线展宽的变化不大。(6)对径向准直器进行了性能评价，以限制1mm的标距体积。测量的轮廓与模拟的结果相同。可以足够精确地测量应力。