Study ot the stress corrosion cracking in the weld seam of low alloyed steels with particular regard to the steel T24

低合金钢焊缝应力腐蚀开裂研究，特别是T24钢

• 批准号: 257480435
• 负责人: Professor Dr.-Ing. Wolfgang Tillmann
• 金额: --
• 依托单位: Lehrstuhl für Werkstofftechnologie (LWT)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2014
• 资助国家: 德国
• 起止时间: 2013-12-31 至 2016-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/257480435?language=en
• 关键词: Study; ot; stress; corrosion; cracking

Under certain operational conditions (combination of mechanical and corrosive loading at temperatures in the range from 120 to 250°C), an unwanted stress corrosion cracking (SCC) in the region of the weld seams is observed in the steel 7CrMoVTiB10-10 (T24). Within the frame of this project, the mechanisms of this crack initiation and crack propagation process and the possibility to influence using pretreatments [welding, thermal treatment, preoxidation) and the loading conditions (strain rate at monotonic deformation, parameters of superimposed cyclic loading, temperature, O2 content and pH value of the aqueous medium) are studied thoroughly. The aim of the project is the identification of microstructural, environmental and loading factors and criteria that effect the susceptibility to SCC of the material in the region of the weld seam, significantly. After the evaluation of the results, the proposers will determine suitable measures to improve the resistance of the material to SCC. Various commercial measuring as well as analytical procedures will be used for these studies (SEM, SEM-EDX analysis, nanoindentation, optical profile analysis with an infinite focus microscope, residual stress measurements using X-rays and neutrons). Additionally, test methods developed by the proposers will be adapted to the requirements of this project and employd for the studies (slow strain rate tests in high temperature water with controlled water chemistry and a simultaneous analysis of surface strain fields and acoustic signals emitted form the volume). The expected contributions to the existing knowledge and understanding of the SCC phenomena in the weld seam of the steel T24 are also of significance for other ferritic and bainitic, low alloyed and heat-resistant steels.

在某些操作分区下，在钢接缝区域中的SION裂纹（SCC）在该项目的框架和裂纹过程过程中观察到钢接缝区域（T24）。 ，预氧化）（单调变形，叠加环的参数，温度，O2含量和水性培养基的pH值）彻底研究了该项目的目的。对焊缝中的材料的敏感性显着，提案者将确定改善SCC材料的措施。光学分析。用于使用X射线和中子的残留应力测量。同时发出的表面应变场和声学信号构成了体积的质量。 。