Entwicklung eines Lebensdauervorhersagekonzepts im VHCF-Bereich auf der Basis kovariater mikrostruktureller Merkmalsgrößen

基于协变量微观结构特征尺寸的 VHCF 领域寿命预测概念的开发

• 批准号: 239363299
• 负责人: Professor Dr.-Ing. Hans Jürgen Christ
• 金额: --
• 依托单位: Department Mathematik
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2013
• 资助国家: 德国
• 起止时间: 2012-12-31 至 2016-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/239363299?language=en
• 关键词: Entwicklung; eines; Lebensdauervorhersagekonzepts; im; VHCF

The aim of the desired project is the study of statistical models and methods for a fatigue lifeprediction concept with the utmost possible accuracy as well as its experimental validation in theVHCF range. Already available and additional fatigue results and microstructural analysesregarding the VHCF behavior for two structural materials, the Ni-base superalloy Nimonic 80A undthe austenitic steel 1.4301, serve as database. The proposed mathematical research work cangenerally be attributed to the field of extreme value theory under consideration of covariateinformation. The covariate information relates to failure-governing microstructural features (e.g.maximum inclusion size, misorientation of neighboring grains, surface roughness etc.). Using theextreme value theory the conditional distribution of a specimen fatigue life depending on theapplied stress amplitude as well as complex covariates should be simulated and fitted to the dataobtained. Hence, a basis for the development of well-grounded evidences for appropriate riskparameters such as stress and number of cycles to failure as basis for the well-known SN-curve iscreated. The close link between the statistical simulation and experimental investigations is acentral part of the project. The experimental results for two structural materials in the VHCF rangeshould immediately enter into the statistical modeling, and the obtained findings should be used forthe design of experiments.

所需项目的目的是研究统计模型和方法的疲劳寿命预测的概念，尽可能准确，以及其实验验证在theVHCF范围。作为数据库，已有的和额外的疲劳结果和微观结构分析关于两种结构材料的VHCF行为，镍基高温合金Nimonic 80A和奥氏体钢1.4301。所提出的数学研究工作一般可归于考虑协变量信息的极值理论领域。协变量信息与失效控制微观结构特征（例如，最大夹杂物尺寸、相邻晶粒的取向差、表面粗糙度等）有关。利用极值理论，可以模拟出试样疲劳寿命随应力幅值和复杂协变量的条件分布，并与所获得的数据进行拟合.因此，建立了一个基础，为适当的风险参数，如应力和失效循环次数，作为众所周知的SN曲线的基础，发展良好的证据。统计模拟和实验研究之间的密切联系是该项目的核心部分。两种结构材料在VHCF范围内的实验结果应立即进入统计建模，所得结果应用于实验设计。