(一) 断裂是一个复杂过程,大致可分为形成和发展两个阶段:在形成阶段包括晶格中质点位错的累积和一个或几个微裂面的开始;在发展阶段表现为物体中一个或几个裂面的伸展。断裂形成阶段该阶段也可以说是酝酿期,或应力累积期,由剪切引起滑移条带,相当于受应力后金属光面上的“吕德氏纹”(Lüder Bands),在单晶和粗粒多晶材料以及有 (A) Fracture is a complicated process that can be roughly divided into two stages of formation and development: the accumulation of particle dislocations in the lattice at the formation stage and the start of one or a few microcracks; in the stage of development, One or a few cracks in the extension. Fracture formation phase This phase can also be said to be gestation period or stress accumulation period, resulting in slip bands due to shearing, which is equivalent to the “Lüder Bands” on the polished metal surface under stress. And coarse-grained polycrystalline materials and there