Mu Yuan
Because most of metals are comprised of many grains, properties such as yield strength and ductility (i.e. elongation to fracture) are also highly dependent on the microstructure. Once again, the influence of both of these factors can be rationalized by considering the motion of dislocation. If dislocation motion is unhibited (i.e. motion is initiated easily and continues withiout hindrance), the strength will be low and relatively little work hardeing will occur. In contrast, the presence of obstacles, or barriers,within the microstructure slow dislocation motion, resulting in an increase in strength.
yield strength 屈服强度
ductility 塑性
microstructure 显微组织
dislocation 位错
work hardening加工硬化