Use of gamma-magnetic test methods for the evaluation of the damage evolution in metallic materials subjected to cyclic loading

使用伽玛磁测试方法评估循环载荷下金属材料的损伤演变

• 批准号: 440056409
• 负责人: Professor Dr.-Ing. Peter Starke
• 金额: --
• 依托单位: Fachgebiet Werkstoffkunde und Werkstoffprüfung
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2020
• 资助国家: 德国
• 起止时间: 2019-12-31 至 2021-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/440056409?language=en
• 关键词: Use; gamma; magnetic; test; methods

In order to achieve the goal of a (residual) fatigue life calculation for metallic materials or structures, it is necessary that comprehensive information is determined and made available. This information describes the microstructure and the associated material mechanisms, whereby their non-destructive determination is an essential aspect, especially for components in service. In addition to external and internal loads and strains, it is the chemical composition and the material’s condition in particular that define and ultimately limit the residual service life. Using conventional analytical methods, these influencing factors can usually only be measured destructively. In principle, magnetic measuring methods are able to detect microstructural differences in metallic materials, which has been proven by numerous investigations in the past. However, so far this evaluation could only be carried out qualitatively, which inevitably requires further systematic investigations as calibration for a quantitative characterization. This is where the planned project comes in and is intended to make a further contribution to the improvement of magnetic measuring methods within the framework of (residual) fatigue life calculation as well as estimation methods for metallic materials. Within the investigations on the unalloyed and low-alloyed carbon steels C22R (SAE 1023) and 20MnCrS5 (SAE 5120), the magnetic property-stress-microstructure relationship is to be developed and made usable for the evaluation by means of magnetic measuring procedures. The two materials intended for the investigations have comparable chemical compositions which differ significantly only in manganese and chromium content. In addition, the influence of the condition of the material as a result of heat treatments as well as the load due to superimposed mean stresses will be investigated.These parameters to be developed will be integrated into the StressLife fatigue life calculation method and finally validated on the above-mentioned investigated materials. In addition to the characterization of fatigue behavior by means of stress-strain hysteresis measurement as well as thermometry and resistometry, the Barkhausen noise in particular will be used as a µmagnetic method and parameters describing the microstructure will be derived by means of a signal analysis. Prior investigations show that methods based on µmagnetics can in principle be used to characterize the fatigue behavior. For further quantification of the results in the context of a fatigue life calculation, however, systematic investigations of the measuring phenomena and the material mechanisms behind them are necessary.

为了实现金属材料或结构的（剩余）疲劳寿命计算的目标，有必要确定并提供全面的信息，这些信息描述了微观结构和相关的材料机制，因此它们的无损确定是必要的。一个重要的方面，特别是对于使用中的部件来说，除了外部和内部载荷和应变之外，化学成分和材料的状况尤其决定并最终限制剩余使用寿命。使用传统的分析方法，这些影响因素可以。通常只能进行破坏性测量。磁性原理测量方法能够检测金属材料的微观结构差异，这已被过去的大量研究所证明，但迄今为止这种评估只能进行定性，这不可避免地需要进一步的系统研究作为定量的校准。这就是计划项目的切入点，旨在为（残余）疲劳寿命计算框架内的磁性测量方法以及非合金材料的估计方法的改进做出进一步的贡献。和低合金碳对于钢 C22R (SAE 1023) 和 20MnCrS5 (SAE 5120)，将开发磁性-应力-微观结构关系，并可用于通过磁性测量程序进行评估。这两种材料具有相似的化学成分。仅锰和铬含量存在显着差异。此外，热处理造成的材料状况以及叠加平均应力造成的载荷也会产生影响。这些待开发的参数将被集成到 StressLife 疲劳寿命计算方法中，并最终在上述研究的材料上进行验证，此外还通过应力应变滞后测量以及温度测量和测量来表征疲劳行为。电阻测量法，特别是巴克豪森噪声将被用作微磁方法，并通过信号分析来描述微观结构的参数。先前的研究表明，基于微磁的方法原则上可用于表征。然而，为了在疲劳寿命计算中进一步量化结果，有必要对测量现象及其背后的材料机制进行系统研究。