2章金属の結晶構造 - cis.kit.ac.jp

1 1 2 (units) SI SI (the international standard of units) 1,245,000 Pa (atomic bonding) (atom) (nucleus) (electron) (closed shell) (ionic bond) NaCl Al2O3 (covalent bond) C Si (metallic bond) Fe Al Ti (crystalline structure) (crystal) ( ) (space lattice) (unit lattice) 1 (lattice constant) a,b,c (1) (BCC)(2) (FCC)(3) (HCP) (body centered cubic lattice, BCC) Cr -Fe Mo -Ti V 8 2 (=1/8 8+1)

2 68 % 2/3a =33124334aa (face centered cubic lattice, FCC) Al Cu -Fe Ni 12 4 (=1/8 8+1/2 6) 74 % 2/2a =33144234aa (hexagonal close-packed lattice, HCP) -Ti Zn 12 6 (=1/2 2+1/6 12+3) (c/a= ) 74 % ) () (4/3/22> <+acaacca = )2/33(16423423 2 (a).. FCC, (b).. (transformation) ( ) (transformation point) Fe (BCC) 912 C (FCC) 1394 C (BCC)Ti (HCP) 882 C (BCC) , , , .. (Miller index) 8x y z a/ a/ a/ h k l ( hkl ) x y z a/2 a/3 a ( 231 ) ( ) h k l [ hkl ] (a a a) [111] ( 110 ) 0 (=1/ ) ( 010 ) ( 100 ) ( 010 ) ( 100 ) { 100 } [ 100 ] [ 010 ] [ 100 ] < 100 > a1 a2 a3 c 4 9a1 a2 c a/ a/ c/ h k m l=-(h+k) 3 a a/ c h k m=1:0.

3 1 l=-(h+k) =-1 ( 1011 ) a1 a2 c ( ) h k m l=-(h+k) (lattice defect) (single crystal) (crystal orientation) (polycrystalline material) (crystal grain) (grain boundary) 1(1-1) 3 (1-2) 3 (1-3) .. 2 a (2-1) (2-2) { 110 } < 111 > ( 110 ) [ 111 ] (2-3) 3 (3-1) (3-2) { 0001 } < 1210 > ( 0001 ) [ 1210 ] (3-3) (c/a= ) 2 11 1(1-1) (1-2) (1-3) 2 (2-1) (2-2) (2-3) a 2 3 (3-1) (3-2) (3-3) a 6 2 232222aaaa=++%6812433433= =aaVf % )2/33(1623423= =aaaVf