图 固溶强化 ⊙日日o⊙92 Be ⑨色o西为力 Oee①①0 066R59的 ǒo595o5 Q00R⊙99 Si 088P838 Sn 0⊙0●O⊙Q (a) 999⊙8Q8 099 A1 5©86 80 Cu+20%24 Ni Cu+10%2 Cu+7%Zn Zn 20 0⊙0⊙0⊙o Cu 0⊕⊕⊕⊙⊙Q ©⊙⊕④⊙e 0⊕⊙⊙①©® 10 0⊙9δ99p 10 20 30 :va0.02 合金元素含量（质量%） 图12？Cu-Zn单晶293K时-y曲线 材料科学与工程学院 16 School of Materials Science and Engineering
材料科学与工程学院 School of Materials Science and Engineering 固溶强化 16
③ 位错Dislocation dislocation line dislocation line Burgers vector,b b是 材料科学与工程学院 17 School of Materials Science and Engineering
材料科学与工程学院 School of Materials Science and Engineering 位错 Dislocation 17
塑性变形 If a material deforms plastically,it changes its shape. Correspondingly,the atoms of a crystal have to change their positions. (a) (b) 件件子习工程学院 18 School of Materials Science and Engineering
材料科学与工程学院 School of Materials Science and Engineering 18 If a material deforms plastically, it changes its shape. Correspondingly, the atoms of a crystal have to change their positions. 塑性变形
图 塑性变形 Debye-Scherrer diagrams of (a) (a)undeformed and(b)deformed copper (a) (b) (b) (c) Plastic deformation of a specimen under tensile stress by slip.(a)Before deformation;(b)after deformation;(c) stretched in single crystal. 材料科学与工程学院 19 School of Materials Science and Engineering
材料科学与工程学院 School of Materials Science and Engineering 塑性变形 19 Debye-Scherrer diagrams of (a) undeformed and (b) deformed copper Plastic deformation of a specimen under tensile stress by slip. (a) Before deformation; (b) after deformation; ( c) stretched in single crystal
图 塑性变形 “Theoretical shear strength”is much higher than observed strength values. Tmax=G/10 max Formation motion of dislocations was postulated to explain this. Dislocations can be much easier to move as applied stress just makes a few atoms move a small distance b) 材料科学与工程学院 20 School of Materials Science and Engineering
材料科学与工程学院 School of Materials Science and Engineering 塑性变形 20