Versteylen C D, Sluiter M H F, van Dijk N H
1Fundamental Aspects of Materials and Energy, Faculty of Applied Sciences, Delft University of Technology, Mekelweg 15, 2629 JB Delft, The Netherlands.
2Virtual Materials and Mechanics, Department of Materials Science and Engineering, Delft University of Technology, Mekelweg 2, 2628 CD Delft, The Netherlands.
J Mater Sci. 2018;53(20):14758-14773. doi: 10.1007/s10853-018-2666-9. Epub 2018 Jul 17.
A self-consistent model is applied to predict the creep cavity growth and strain rates in metals from the perspective of self-healing. In this model, the creep cavity growth rate is intricately linked to the strain rate. The self-healing process causes precipitates to grow inside creep cavities. Due to the Kirkendall effect, a diffusional flux of vacancies is induced in the direction away from the creep cavity during this selective self-healing precipitation. This process impedes the creep cavity growth. The critical stress for self-healing can be derived, and an analysis is made of the efficiency of self-healing elements in binary Fe-Cu, Fe-Au, Fe-Mo, and Fe-W alloys. Fe-Au is found to be the most efficient self-healing alloy. Fe-Mo and Fe-W alloys provide good alternatives that have the potential to be employed at high temperatures.
应用一个自洽模型从自愈合的角度预测金属中的蠕变空洞生长和应变率。在该模型中，蠕变空洞生长率与应变率紧密相关。自愈合过程使析出物在蠕变空洞内生长。由于柯肯达尔效应，在这种选择性自愈合析出过程中，空位的扩散通量在远离蠕变空洞的方向上被诱导产生。这个过程阻碍了蠕变空洞的生长。可以推导出自愈合的临界应力，并对二元Fe-Cu、Fe-Au、Fe-Mo和Fe-W合金中自愈合元素的效率进行了分析。发现Fe-Au是最有效的自愈合合金。Fe-Mo和Fe-W合金是很好的替代品，有可能在高温下使用。
