MSE 220 Fall 2018 - Quiz 2
October 4, 2018
Name: ________Solution__________________________
Discussion 101 102 103 104 105
Honor Pledge (write out):
______________________________________________________________________________
______________________________________________________________________________
Signature: ________________________________
1
, 1. (6 pts) List the three types of imperfections, or defects, we see in crystalline metals and
provide an example of each type.
Point - vacancy or substitutional or interstitial
Line - dislocation
Planar - grain boundary or surface
2. (5 pts) You are given an alloy containing 100 g of Fe and 2 g of C.
a. Determine the composition of the alloy in weight percent.
𝑤𝑤𝑤𝑤𝑤𝑤𝑤𝑤 100𝑔𝑔
𝑤𝑤𝑤𝑤%𝐹𝐹𝐹𝐹 = 𝑥𝑥100 = 𝑥𝑥100 = 98.04𝑤𝑤𝑤𝑤%𝐹𝐹𝐹𝐹
𝑤𝑤𝑤𝑤𝑤𝑤𝑤𝑤 + 𝑤𝑤𝑤𝑤𝑤𝑤 100𝑔𝑔 + 2𝑔𝑔
Or
𝑤𝑤𝑤𝑤𝑤𝑤 2𝑔𝑔
𝑤𝑤𝑤𝑤%𝐶𝐶 = 𝑥𝑥100 = 𝑥𝑥100 = 1.96𝑤𝑤𝑤𝑤%𝐶𝐶
𝑤𝑤𝑤𝑤𝑤𝑤𝑤𝑤 + 𝑤𝑤𝑤𝑤𝑤𝑤 100𝑔𝑔 + 2𝑔𝑔
b. Determine the composition of the alloy in atomic percent knowing the atomic mass of Fe is
55.85 g/mol and of C is 12.01 g/mol.
𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚 100𝑔𝑔
𝑁𝑁𝐹𝐹𝐹𝐹 𝐴𝐴𝐴𝐴𝐹𝐹𝐹𝐹 55.85𝑔𝑔/𝑚𝑚𝑚𝑚𝑚𝑚
𝑎𝑎𝑎𝑎%𝐹𝐹𝐹𝐹 = 𝑥𝑥100 = 𝑥𝑥100 = 𝑥𝑥100 = 91.49𝑎𝑎𝑎𝑎%𝐹𝐹𝐹𝐹
𝑁𝑁𝐹𝐹𝐹𝐹 + 𝑁𝑁𝐶𝐶 𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚 𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚 100𝑔𝑔 2𝑔𝑔
+ +
𝐴𝐴𝐴𝐴𝐹𝐹𝐹𝐹 𝐴𝐴𝐴𝐴𝐶𝐶 55.85𝑔𝑔/𝑚𝑚𝑚𝑚𝑚𝑚 12.01𝑔𝑔/𝑚𝑚𝑚𝑚𝑚𝑚
Or
𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚 2𝑔𝑔
𝑁𝑁𝐹𝐹𝐹𝐹 𝐴𝐴𝐴𝐴𝐶𝐶 12.01𝑔𝑔/𝑚𝑚𝑚𝑚𝑚𝑚
𝑎𝑎𝑎𝑎%𝐶𝐶 = 𝑥𝑥100 = 𝑥𝑥100 = 𝑥𝑥100 = 8.51𝑎𝑎𝑎𝑎%𝐶𝐶
𝑁𝑁𝐹𝐹𝐹𝐹 + 𝑁𝑁𝐶𝐶 𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚 𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚 100𝑔𝑔 2𝑔𝑔
+ +
𝐴𝐴𝐴𝐴𝐹𝐹𝐹𝐹 𝐴𝐴𝐴𝐴𝐶𝐶 55.85𝑔𝑔/𝑚𝑚𝑚𝑚𝑚𝑚 12.01𝑔𝑔/𝑚𝑚𝑚𝑚𝑚𝑚
3. (4 pts) We wish to diffusion bond Cu and Zn. If the heat treatment is carried out at 300°C,
what is the diffusion coefficient for Cu diffusing into Zn? What is the diffusion coefficient for Zn
diffusing into Cu?
Cu diffusing into Zn
𝑄𝑄 124000𝐽𝐽/𝑚𝑚𝑚𝑚𝑚𝑚
− −
𝐷𝐷 = 𝐷𝐷𝑜𝑜 𝑒𝑒 𝑅𝑅𝑅𝑅 = (2.1𝑥𝑥10−4 𝑚𝑚2 /𝑠𝑠)𝑒𝑒 8.314𝑗𝑗/𝑚𝑚𝑚𝑚𝑚𝑚∙𝐾𝐾(573𝐾𝐾) = 1.04𝑥𝑥10−15 𝑚𝑚2 /𝑠𝑠
Zn diffusing into Cu
𝑄𝑄 189000𝐽𝐽/𝑚𝑚𝑚𝑚𝑚𝑚
−
𝐷𝐷 = 𝐷𝐷𝑜𝑜 𝑒𝑒 −𝑅𝑅𝑅𝑅 = (2.4𝑥𝑥10−5 𝑚𝑚 2
/𝑠𝑠)𝑒𝑒 8.314𝑗𝑗/𝑚𝑚𝑚𝑚𝑚𝑚∙𝐾𝐾(573𝐾𝐾) = 1.41𝑥𝑥10−22 𝑚𝑚2 /𝑠𝑠
2
October 4, 2018
Name: ________Solution__________________________
Discussion 101 102 103 104 105
Honor Pledge (write out):
______________________________________________________________________________
______________________________________________________________________________
Signature: ________________________________
1
, 1. (6 pts) List the three types of imperfections, or defects, we see in crystalline metals and
provide an example of each type.
Point - vacancy or substitutional or interstitial
Line - dislocation
Planar - grain boundary or surface
2. (5 pts) You are given an alloy containing 100 g of Fe and 2 g of C.
a. Determine the composition of the alloy in weight percent.
𝑤𝑤𝑤𝑤𝑤𝑤𝑤𝑤 100𝑔𝑔
𝑤𝑤𝑤𝑤%𝐹𝐹𝐹𝐹 = 𝑥𝑥100 = 𝑥𝑥100 = 98.04𝑤𝑤𝑤𝑤%𝐹𝐹𝐹𝐹
𝑤𝑤𝑤𝑤𝑤𝑤𝑤𝑤 + 𝑤𝑤𝑤𝑤𝑤𝑤 100𝑔𝑔 + 2𝑔𝑔
Or
𝑤𝑤𝑤𝑤𝑤𝑤 2𝑔𝑔
𝑤𝑤𝑤𝑤%𝐶𝐶 = 𝑥𝑥100 = 𝑥𝑥100 = 1.96𝑤𝑤𝑤𝑤%𝐶𝐶
𝑤𝑤𝑤𝑤𝑤𝑤𝑤𝑤 + 𝑤𝑤𝑤𝑤𝑤𝑤 100𝑔𝑔 + 2𝑔𝑔
b. Determine the composition of the alloy in atomic percent knowing the atomic mass of Fe is
55.85 g/mol and of C is 12.01 g/mol.
𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚 100𝑔𝑔
𝑁𝑁𝐹𝐹𝐹𝐹 𝐴𝐴𝐴𝐴𝐹𝐹𝐹𝐹 55.85𝑔𝑔/𝑚𝑚𝑚𝑚𝑚𝑚
𝑎𝑎𝑎𝑎%𝐹𝐹𝐹𝐹 = 𝑥𝑥100 = 𝑥𝑥100 = 𝑥𝑥100 = 91.49𝑎𝑎𝑎𝑎%𝐹𝐹𝐹𝐹
𝑁𝑁𝐹𝐹𝐹𝐹 + 𝑁𝑁𝐶𝐶 𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚 𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚 100𝑔𝑔 2𝑔𝑔
+ +
𝐴𝐴𝐴𝐴𝐹𝐹𝐹𝐹 𝐴𝐴𝐴𝐴𝐶𝐶 55.85𝑔𝑔/𝑚𝑚𝑚𝑚𝑚𝑚 12.01𝑔𝑔/𝑚𝑚𝑚𝑚𝑚𝑚
Or
𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚 2𝑔𝑔
𝑁𝑁𝐹𝐹𝐹𝐹 𝐴𝐴𝐴𝐴𝐶𝐶 12.01𝑔𝑔/𝑚𝑚𝑚𝑚𝑚𝑚
𝑎𝑎𝑎𝑎%𝐶𝐶 = 𝑥𝑥100 = 𝑥𝑥100 = 𝑥𝑥100 = 8.51𝑎𝑎𝑎𝑎%𝐶𝐶
𝑁𝑁𝐹𝐹𝐹𝐹 + 𝑁𝑁𝐶𝐶 𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚 𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚 100𝑔𝑔 2𝑔𝑔
+ +
𝐴𝐴𝐴𝐴𝐹𝐹𝐹𝐹 𝐴𝐴𝐴𝐴𝐶𝐶 55.85𝑔𝑔/𝑚𝑚𝑚𝑚𝑚𝑚 12.01𝑔𝑔/𝑚𝑚𝑚𝑚𝑚𝑚
3. (4 pts) We wish to diffusion bond Cu and Zn. If the heat treatment is carried out at 300°C,
what is the diffusion coefficient for Cu diffusing into Zn? What is the diffusion coefficient for Zn
diffusing into Cu?
Cu diffusing into Zn
𝑄𝑄 124000𝐽𝐽/𝑚𝑚𝑚𝑚𝑚𝑚
− −
𝐷𝐷 = 𝐷𝐷𝑜𝑜 𝑒𝑒 𝑅𝑅𝑅𝑅 = (2.1𝑥𝑥10−4 𝑚𝑚2 /𝑠𝑠)𝑒𝑒 8.314𝑗𝑗/𝑚𝑚𝑚𝑚𝑚𝑚∙𝐾𝐾(573𝐾𝐾) = 1.04𝑥𝑥10−15 𝑚𝑚2 /𝑠𝑠
Zn diffusing into Cu
𝑄𝑄 189000𝐽𝐽/𝑚𝑚𝑚𝑚𝑚𝑚
−
𝐷𝐷 = 𝐷𝐷𝑜𝑜 𝑒𝑒 −𝑅𝑅𝑅𝑅 = (2.4𝑥𝑥10−5 𝑚𝑚 2
/𝑠𝑠)𝑒𝑒 8.314𝑗𝑗/𝑚𝑚𝑚𝑚𝑚𝑚∙𝐾𝐾(573𝐾𝐾) = 1.41𝑥𝑥10−22 𝑚𝑚2 /𝑠𝑠
2
