Tunable stacking fault energies by tailoring local chemical order in CrCoNi medium-entropy alloys

High-entropy alloys (HEAs) are an intriguing new class of metallic materials due to their unique mechanical behavior. Achieving a detailed understanding of structure-property relationships in these materials has been challenged by the compositional disorder that underlies their unique mechanical behavior. Accordingly, in this work, we employ first-principles calculations to investigate the nature of local chemical order and establish its relationship to the intrinsic and extrinsic stacking fault energy (SFE) in CrCoNi medium-entropy solid-solution alloys, whose combination of strength, ductility and toughness properties approach the best on record. We find that the average intrinsic and extrinsic SFE are both highly tunable, with values ranging from -43 mJ.m-2 to 30 mJ.m-2 and from -28 mJ.m-2 to 66 mJ.m-2, respectively, as the degree of local chemical order increases. The state of local ordering also strongly correlates with the energy difference between the face-centered cubic (fcc) and hexagonal-close packed (hcp) phases, which affects the occurrence of transformation-induced plasticity. This theoretical study demonstrates that chemical short-range order is thermodynamically favored in HEAs and can be tuned to affect the mechanical behavior of these alloys. It thus addresses the pressing need to establish robust processing-structure-property relationships to guide the science-based design of new HEAs with targeted mechanical behavior.Comment: 23 pages, 5 figure

On the Application of Translation Quality Assessment Model in MTI Teaching

The 21st century is an era of globalization with rapid development of information technology and there are more and more close exchanges among countries. Under this background, the importance of translation is self-evident, and MTI (Master of Translation and Interpreting) teaching, which is closely related to it, has also attracted increasing attention. On the whole, after over ten years of development, translation teaching in China has begun to take shape. Both major foreign language colleges and foreign language departments of various comprehensive colleges have set up corresponding translation courses. But at present, the teaching effect of MTI is far from satisfaction. Based on the translation quality assessment model of Malcolm Williams, the necessity and possibility of the application of the translation quality assessment model in MTI teaching is explored, and the concept of the application of the translation quality assessment model in the classroom is put forward, aiming to establish an objective and effective evaluation system in MTI teaching so as to further promote the development of MTI teaching