Trinkle Dallas R, Woodward Christopher
Materials and Manufacturing Directorate, Air Force Research Laboratory, Wright Patterson Air Force Base, Dayton, OH 45433-7817, USA.
Science. 2005 Dec 9;310(5754):1665-7. doi: 10.1126/science.1118616.
Solutes have been added to strengthen elemental metals, generating usable materials for millennia; in the 1960s, solutes were found to also soften metals. Despite the empirical correlation between the "electron number" of the solute and the change in strength of the material to which it is added, the mechanism responsible for softening is poorly understood. Using state-of-the-art quantum-mechanical methods, we studied the direct interaction of transition-metal solutes with dislocations in molybdenum. The interaction increases dramatically with increasing electron number and strongly influences the mechanisms responsible for plasticity in these materials. Our quantitative model explains solution softening of metals by using changes in energy and stress scales of plasticity from solutes.
溶质被添加到金属中以强化金属元素，数千年来一直用于制造可用材料；20世纪60年代，人们发现溶质也会使金属软化。尽管溶质的“电子数”与添加溶质的材料强度变化之间存在经验关联，但导致软化的机制仍知之甚少。我们使用最先进的量子力学方法，研究了过渡金属溶质与钼中位错的直接相互作用。这种相互作用随着电子数的增加而急剧增强，并强烈影响这些材料中负责塑性的机制。我们的定量模型通过溶质引起的塑性能量和应力尺度变化来解释金属的固溶软化现象。
