Fundamentals of Materials Science and Engineering: An Integrated Approach, 3e

GTBL042-answers GTBL042-Callister-v3 October 11, 2007 13:37

Revised Pages

Answers to Selected Problems • 857

10.27For pointA,F= 2

10.28C′ 0 = 0 .69 wt% C

10.33Not possible

10.36HB (alloy)= 141

10.37 (a)T(eutectoid)= 700 ◦C (1290◦F);

(b)ferrite;

(c)Wα′= 0. 20 ,Wp= 0. 80

Chapter 11

11.2 (a)G∗= 1. 27 × 10 −^18 J

11.4rate= 2. 69 × 10 −^2 s−^1

11.6 (c)t∼=250 days

11.12 (b)100% spheroidite

(c)60% bainite and 40% martensite

11.17 (a)Austenitize at about 720◦C; cool to

room temperature at a rate between 0.02

and 0.006◦C/s

11.21 (b)87 HRB

11.23 (b)Rapidly cool to about 630◦C (1170◦F),

hold for about 25 s, then cool to room

temperature.

11.D5Heat for about 10 h at 149◦C

Chapter 12

12.3 (a)R= 6. 7 × 10 −^3 ;(b)I= 6 .0A;

(c)J= 3. 06 × 105 A/m^2 ;

(d)e= 8. 0 × 10 −^3 V/m

12.7 (a)ρ 0 = 1. 58 × 10 −^8 -m,

a= 6. 5 × 10 −^11 (-m)/◦C;

(b)A= 1. 18 × 10 −^6 -m;

(c)ρ= 5. 24 × 10 −^8 -m

12.10ni= 1. 95 × 1021 m−^3

12.12σ= 0 .028 (-m)−^1

12.15 (a)n= 1. 44 × 1016 m−^3 ;

(b)p-type extrinsic

12.17σ= 94 .4(-m)−^1

12.20σ=1040 (-m)−^1

12.21σ=128 (-m)−^1

12.26l= 3 .36 mm (0.135 in.)

12.28 pi= 1. 92 × 10 −^30 C-m

12.29 (a)V= 39 .7V;(b)V=139 V;

(e)P= 2. 20 × 10 −^7 C/m^2

12.D2Not possible

Chapter 13

13.2VGr= 8 .1 vol%

13.8 (a)T= 2220 ◦C (4030◦F)

13.9 (a)WL= 0. 73

Chapter 14

14.5 (a)At least 915◦C (1680◦F)

14.12 (b)Qvis=208,000 J/mol

14.D3Maximum diameter=50 mm (2 in.)

Chapter 15

15.3 (b)l=25 mm (1.0in.)

15.5 Ef=104 GPa (15× 106 psi);

Em= 2 .6 GPa (3. 77 × 105 psi)

15.7 (a)Ff/Fm= 44 .7;

(b)Ff=52,232 N (11,737 lbf),

Fm=1168 N (263 lbf);

(c)σf=242 MPa (34,520 psi);

σm= 4 .4 MPa (641 psi);

(d)= 1. 84 × 10 −^3

15.9 σcd∗=822 MPa (117,800 psi)

15.D1Carbon (PAN standard-modulus)

Chapter 16

16.2 (a)V= 0 .011 V;

(b)Sn^2 ++Pb→Sn+Pb^2 +

16.3 [Cu^2 +]= 0. 784 M

16.9 CPR=36.5 mpy

16.10 (a)r= 4. 56 × 10 −^12 mol/cm^2 -s;

(b)VC=− 0 .0167 V

16.15 Mg: P-B ratio=0.81; nonprotective

16.16 (a)Parabolic kinetics;

(b)W= 3 .70 mg/cm^2

Chapter 17

17.1 E(brass)= 2. 44 × 105 J

E(alumina)= 5. 04 × 105 J

17.5 αl= 15. 0 × 10 −^6 (◦C)−^1

17.7Tf= 222. 4 ◦C

17.8 (b)dQ/dt= 2. 88 × 109 J/h (2. 73 × 106 Btu/h)

17.14Tf= 41. 3 ◦C (106◦F)

17.15 d= 0 .0375 mm

17.D1Tf= 41. 8 ◦C (107. 3 ◦F)

17.D2Soda-lime glass:Tf= 111 ◦C

Chapter 18

18.1 (a)H=24,000 A-turns/m;

(b)B 0 = 3. 017 × 10 −^2 tesla;

(c)B∼= 3. 018 × 10 −^2 tesla;

(d)M= 7 .51 A/m

18.5 nB= 1 .14 Bohr magnetons/atom

18.7 2.86 Bohr magnetons/Sm^3 +ion