Development of the peening processes micropeening and ultrasonic wet peening to work hardening

开发微喷丸和超声波湿喷丸加工硬化喷丸工艺

基本信息

批准号：
240450756
负责人：
Professor Dr.-Ing. Volker Schulze
金额：
--
依托单位：
Institut für Angewandte Materialien - Werkstoffkunde (IAM-WK)
依托单位国家：
德国
项目类别：
Research Grants
财政年份：
2013
资助国家：
德国
起止时间：
2012-12-31 至 2018-12-31
项目状态：
已结题

来源：
https://gepris.dfg.de/gepris/projekt/240450756?language=en
关键词：
Development peening processes micropeening ultrasonic

项目摘要

The processes micro-peening and ultrasonic wet peening offer the possibility of mechanical surface treatment to significantly increase fatigue strength of steels, with several advantages over established methods such as shot peening. This includes not only a high surface quality with little effect of blasting media impacts on the roughness but also a very low peening intensity, which allows for the processing of thin-walled components. Another notable effect is the occurrence of nanocrystalline regions on the surface, which affect the mechanical properties of the boundary layer. In the first phase of the grant Armco iron was used as the model material to separate the factors influencing the fatigue strength and are based on developed and validated a material model of grain refinement and consolidation of a modified concept of local endurance. In the second phase of the project this understanding of the mechanisms will now be transferred to the quenched and tempered steel 42CrMo4 V450. This bears the difficulty that a parameter separation by heat treatment as in the Armco iron, is not possible. Furthermore, the individual states of the boundary layer cannot be clearly separated in this heat treatment condition. In addition, the heavily modified deformation behavior, which also affects the surface layer state, must be considered in the modelling approach. The concept to be developed on the basis of previous FEM simulations will also be validated with an experimental characterization of the microstructure and the fatigue behavior. This is to be finally applied to a sequential mechanical surface treatment of conventional shot peening followed by micro-peening or ultrasonic wet peening. This should achieve an optimized combination of high penetration with optimized near-surface properties so that a significant increase in lifetime results for thick-walled components.

微螺旋和超声波湿式的过程提供了机械表面处理的可能性，可以显着提高钢的疲劳强度，而与已建立的方法（如射击式”等方法具有多种优势。这不仅包括高表面质量，几乎没有爆炸介质对粗糙度的影响，而且还包括非常低的镀锡强度，从而可以处理薄壁的组件。另一个值得注意的效果是表面上的纳米晶区域的发生，这会影响边界层的机械性能。在赠款的第一阶段，ARMCO铁被用作模型材料，以分离影响疲劳强度的因素，并基于开发和验证的晶粒细化的材料模型以及对局部耐力的修改概念的合并。在项目的第二阶段中，对机制的理解现在将转移到淬火和回火的42CRMO4 V450中。这是一个难以通过热处理与ARMCO铁进行的参数分离的困难。此外，在这种热处理条件下，边界层的各个状态无法明确分离。另外，在建模方法中必须考虑经过重大修改的变形行为，这也影响了表面层状态。基于先前的FEM模拟的概念也将通过微观结构和疲劳行为的实验表征来验证。这将最终应用于传统射击式固定的连续机械表面处理，然后是微螺旋或超声湿式镀锡。这应该将高渗透率与优化的近表面特性实现优化的组合，从而使厚壁组件的寿命结果显着增加。