ch07_应变硬化与退火_E_2.ppt

* Figure 7.13 Shot peen the shaft 轴（表面）喷丸强化 * Section 7.5 Characteristics of Cold Working冷加工的特性 ?2003 Brooks/Cole, a division of Thomson Learning, Inc. Thomson Learning? is a trademark used herein under license. Figure 7.14 A comparison of strengthening copper by (a) cold working and (b) alloying with zinc. Note that cold working produces greater strengthening, yet has little effect on electrical conductivity.比较铜的强化效果(a)通过冷加工强化(b)与锌形成合金强化。注意冷加工导致更高的强度，但是对电导率的影响小。 屈服强度 * ?2003 Brooks/Cole, a division of Thomson Learning, Inc. Thomson Learning? is a trademark used herein under license. Figure 7.15 The wire-drawing process. The force Fd acts on both the original and final diameters. Thus, the stress produced in the final wire is greater than that in the original. If the wire did not strain harden during drawing, the final wire would break before the original wire was drawn through the die. 金属丝-拉拔加工。拉力Fd同时作用于前后两种直径的丝上，因此，作用在最终的丝上的应力要高于作用在初始丝上的应力，如果在拉拔加工过程中没有出现应变硬化，在初始丝被拉出模具之前，最终的丝就将会断裂。 * Section 7.6 The Three Stages of Annealing 退火的三个阶段 Recovery - A low-temperature annealing heat treatment designed to eliminate residual stresses introduced during deformation without reducing the strength of the cold-worked material. 回复 – 退火热处理低温阶段，作用是消除变形过程中产生的残余应力，被冷加工的材料强度不降低。 Recrystallization - A medium-temperature annealing heat treatment designed to eliminate all of the effects of the strain hardening produced during cold working. 再结晶 - 退火热处理中温阶段，作用是消除冷加工过程中应变硬化效果。 Grain growth - Movement of grain boundaries by diffusion in order to reduce the amount of grain boundary area. 晶粒长大 – 因扩散导致晶粒边界移动以减少晶粒边界的面积。 * Figure 7.16 Photomicrographs showing the effect of annealing temperature on grain size in brass. Twin boundaries can also be observed in the structures. (a) Annealed at 400oC, (b) annealed at 650oC, and (c) annealed at 800oC (75). 退火处理温度对黄铜中晶粒尺寸的影响(a)400oC退火，(b)650oC退火，(c)800oC退火。 * ?2003 Brooks/Cole, a division of Thomson Learning, Inc. Thomson Learning? i