1 Introduction
2 Grain Refinement of Copper
2.1 Previous Work on Grain Refinement of Copper
2.2 Factors Controlling Secondary Dendrite Arm Spacing and Grain Size: Cooling Rate, Casting Temperature, Casting Atmosphere, Solute Type, and Solute Content
2.3 The Growth Restriction Factor (Q)
3 Experimental
3.1 Materials
3.1.1 High-purity copper cathode (Cu-CATH-1)
3.1.2 DHP-Cu
3.1.3 Alloying additions
3.2 Castings
3.3 Characterization Techniques
3.3.1 Macroscopic examination
3.3.2 Optical microscopy
3.3.3 ICP analysis
3.3.4 SEM
4 Results and Discussion
4.1 Q Factor
m
|
k
|
m (k − 1)
| Invariant reactions and characteristics at the Cu-rich region | Tl [K (°C)] at 0.1 pct | Ts [K (°C)] at 0.1 pct | ΔT (K) at 0.1 pct | Superheat (K) at 0.1 pct 1433 K (1160 °C) | |
---|---|---|---|---|---|---|---|---|
Nb | 25.70 | 4.218 | 82.69 | peritectic | 1360.31 (1087.16) | 1358.38 (1085.23) | 1.93 | 73 |
B | −56.23 | 0.098 | 50.74 | eutectic | 1351.77 (1078.62) | 1287.73 (1014.58) | 64.04 | 81 |
O[42] | −41.86 | 0.017 | 41.13 | eutectic / monotectic | 1351.81 (1078.66) | 1338.00 (1064.85) | 13.81 | 81 |
Mg | −30.90 | 0.075 | 28.58 | eutectic | 1354.79 (1081.64) | 1322.67 (1049.52) | 32.12 | 78 |
−23.83 | 0.016 | 23.44 | eutectic | 1355.60 (1082.45) | 1340.00 (1066.85) | 15.60 | 78 | |
P | −23.73 | 0.092 | 21.55 | eutectic, congruent | 1355.09 (1081.94) | 1336.17 (1063.02) | 18.92 | 78 |
Ca | −20.38 | 0 | 20.38 | eutectic | 1356.43 (1083.28) | 1182.82 (909.67) | 173.61 | 77 |
Tl | −16.76 | 0.045 | 16.00 | monotectic | 1357.53 (1084.38) | 1348.07 (1074.92) | 9.46 | 76 |
Si | −19.80 | 0.376 | 12.35 | peritectic | 1356.24 (1083.09) | 1353.19 (1080.04) | 3.05 | 77 |
Se[24] | −9.94 | 0 | 9.94 | monotectic | 1357.06 (1083.91) | 1336.15 (1063.00) | 20.91 | 76 |
Y | −9.13 | 0 | 9.13 | eutectic | 1356.85 (1083.70) | 1153.41 (880.26) | 203.44 | 76 |
Zr | −8.70 | 0 | 8.70 | eutectic | 1356.85 (1083.70) | 1284.77 (1011.62) | 72.08 | 76 |
Ti | −11.70 | 0.264 | 8.61 | intermediate solid solution phases / compounds | 1356.57 (1083.42) | 1353.07 (1079.92) | 3.50 | 77 |
Sr | −8.23 | 0 | 8.23 | intermediate compounds | 1356.95 (1083.80) | 1118.35 (845.20) | 238.6 | 77 |
Sn | −6.20 | 0.064 | 5.80 | peritectic | 1357.13 (1083.98) | 1348.63 (1075.48) | 8.50 | 76 |
Ge | −8.00 | 0.310 | 5.52 | intermediate solid solution phases | 1357.04 (1083.89) | 1355.39 (1082.24) | 1.65 | 76 |
Mn | −8.68 | 0.397 | 5.23 | miscibility gap in the solid state | 1356.90 (1083.75) | 1355.55 (1082.40) | 1.35 | 76 |
Sb | −5.56 | 0.141 | 4.78 | eutectic, congruent | 1357.20 (1084.05) | 1353.98 (1080.83) | 3.22 | 76 |
Mo | −6.02 | 0.218 | 4.71 | peritectic | 1357.42 (1084.27) | 1357.38 (1084.23) | 0.04 | 76 |
In | −5.55 | 0.203 | 4.42 | peritectic | 1357.24 (1084.09) | 1355.14 (1081.99) | 2.10 | 76 |
Ni | 6.75 | 1.57 | 3.88 | isomorphous | 1358.70 (1085.55) | 1358.46 (1085.31) | 0.24 | 74 |
Te[43] | −3.88 | 0 | 3.88 | monotectic | 1357.61 (1084.46) | 1325.00 (1051.85) | 32.61 | 76 |
Bi | −3.85 | 0 | 3.85 | very low solubility of Bi in Cu | 1356.77 (1083.62) | 1272.18 (999.03) | 84.59 | 76 |
Ag | −4.95 | 0.261 | 3.66 | eutectic | 1357.28 (1084.13) | 1355.97 (1082.82) | 1.31 | 76 |
Cr | −6.54 | 0.489 | 3.34 | eutectic | 1357.09 (1083.94) | 1356.46 (1083.31) | 0.63 | 76 |
Pb | −3.07 | 0.133 | 2.66 | monotectic | 1357.71 (1084.56) | 1355.73 (1082.58) | 1.98 | 75 |
Fe | 5.15 | 1.447 | 2.30 | peritectic | 1358.55 (1085.40) | 1358.40 (1085.25) | 0.15 | 75 |
Au | −1.93 | 0.487 | 0.99 | miscibility gap in the solid state | 1357.58 (1084.43) | 1357.36 (1084.21) | 0.22 | 76 |
Zn | −3.35 | 0.722 | 0.93 | peritectic | 1357.69 (1084.54) | 1357.56 (1084.41) | 0.13 | 75 |
Pt | 1.83 | 1.500 | 0.92 | miscibility gap in the solid state | 1358.11 (1084.96) | 1357.95 (1084.80) | 0.16 | 75 |
V | 2.96 | 1.214 | 0.63 | peritectic | 1358.06 (1084.91) | 1358.01 (1084.86) | 0.05 | 75 |
Al | 0.81 | 1.138 | 0.11 | intermediate solid solution phases | 1358.21 (1085.06) | 1358.19 (1085.04) | 0.02 | 75 |
4.2 Melt Deoxidation
Cast | Casting T [K (°C)] | Nominal Compositions (Wt Pct) | Tl [K (°C)] | Ts [K (°C)] | ΔT (K) | Master alloys/materials (Wt Pct) | Macrostructure | |
---|---|---|---|---|---|---|---|---|
1 | B | 1402 (1129) | 0.4 | 1337.00 (1063.85) | 1287.34 (1014.19) | 49.66 | Cu-1.73B-0.04Si-0.01Fe-0.01Sn-0.005Pb | CET |
2 | O[16] | 1423 (1150) | (1590 wt ppm) copper cathode | 1349.34 (1076.19) | 1338.00 (1064.85) | 11.34 | CET | |
3 | Mg | 1411 (1138) | 0.4 | 1346.12 (1072.96) | 1248.64 (975.49) | 97.48 | Cu-20Mg | CET excessive equiaxed grain coarsening |
4 | 1398 (1125) | 0.8 | 1332.87 (1059.72) | 1179.28 (906.13) | 153.59 | CET | ||
5 | 1372 (1099) | 1.6 | 1306.28 (1033.13) | 1088.18 (815.03) | 218.10 | CET | ||
6 | P[17] | 1423 (1150) | 0.1 (886 wt ppm) | 1355.09 (1081.94) | 1336.171(1063.02) | 18.92 | Cu-15P | CET to a lesser extent |
7 | [17] | 1423 (1150) | 0.5 (4349 wt ppm) | 1346.11 (1072.96) | 1245.05 (971.90) | 101.06 | CET excessive equiaxed grain coarsening | |
8 | 1411 (1138) | 0.5 | 1346.11 (1072.96) | 1245.05 (971.90) | 101.06 | CET | ||
9 | Ca | 1415 (1142) | 0.4 | 1349.53 (1076.38) | 1182.81 (909.66) | 166.72 | Cu-6.87Ca-0.005Al-0.001Fe-0.001Mg | CET excessive equiaxed grain coarsening |
10 | 1406 (1133) | 0.8 | 1341.06 (1067.91) | 1182.12 (908.97) | 158.94 | CET excessive equiaxed grain coarsening | ||
11 | Zr | 1419 (1146) | 0.4 | 1354.16 (1081.01) | 1240.59 (967.44) | 113.57 | Cu-9.28Zr-0.11Sn-0.09Fe-0.002Pb | large columnar/some equiaxed grains |
12 | 1416 (1143) | 0.8 | 1350.41 (1077.26) | 1240.59 (967.44) | 109.82 | large columnar | ||
13 | Ti | 1418 (1145) | 0.4 | 1353.18 (1080.03) | 1339.08 (1065.93) | 14.10 | Cu-28.924Ti-0.045Fe-0.01max.Ni-0.002Pb | large columnar |
14 | 1413 (1140) | 0.8 | 1348.18 (1075.03) | 1322.09 (1048.94) | 26.09 | large columnar |
4.3 Phosphide Particles
Cast | Casting T** [K (°C)] | Nominal Compositions (wt pct) | ICP-OES Trace Analysis (wt ppm) | Macrostructure | |
---|---|---|---|---|---|
15 | B + P | 1402 (1129) | 0.4B, 0.15P | CET excessive equiaxed grain coarsening | |
16 | Mg + P | 1411 (1138) | 0.4Mg, 0.04P | CET excessive equiaxed grain coarsening | |
17 | Ca + P | 1415 (1142) | 0.4Ca, 0.04P | CET excessive equiaxed grain coarsening | |
11
|
Zr
*
|
1419 (1146)
|
0.4Zr
|
3420Zr, 6Pb, 69Fe, 51Sn
|
large columnar/some equiaxed grains
|
18***
| Zr + P | 1419 (1146) | 0.4Zr, 0.04P | 3881Zr, 370P, 70Fe, 5Sn | CET |
19 | Zr + P | 1419 (1146) | 0.4Zr, 0.15P | 2052Zr, 934P, 121Fe, 51Sn | columnar |
20 | Zr + Ag | 1419 (1146) | 0.4Zr, 0.015Ag | 3873Zr, 98Ag | large columnar |
21 | Zr + P + Ag | 1419 (1146) | 0.4Zr, 0.04P, 0.015Ag | CET | |
22 | Ti + P | 1418 (1145) | 0.4Ti, 0.04P | large columnar | |
23***
| Ag + P[17] | 1423 (1150) | 0.1Ag, 0.069P | 940Ag, 390P | CET |
24 | Ag + P[17] | 1423 (1150) | 0.4Ag, 0.03P | CET to a lesser extent | |
25 | Fe + P | 1425 (1152) | 0.4Fe, 0.04P | columnar |
4.4 Qualitative SEM-EDS Analysis of Particles in the B- and Zr-Treated Casts
4.4.1 B-treated casts 1 and 15
4.4.2 Zr-treated casts 11, 18-21
4.5 P and Ag Microalloying Additions
Cast | Casting T [K (°C)] | Nominal Compositions (Wt Pct) | ICP-OES Trace Analysis (Wt ppm) | Macrostructure | |
---|---|---|---|---|---|
26 | P[16] | 1423 (1150) | 0.039P | 300P | CET to a lesser extent |
27 | P[18] | 1403 (1130) | 0.039P | CET to a lesser extent | |
28 | P | 1373 (1100) | 0.039P | CET | |
29 | P + Ag[16] | 1423 (1150) | 0.069P, 0.015Ag | 396P, 143Ag | CET to a lesser extent |
30 | P + Ag[18] | 1403 (1130) | 0.039P, 0.015Ag | CET |
4.6 Microalloying Additions to DHP-Cu Microalloyed with Ag
Cast | Oxides | Density (kg/m3)[35] ×10−3
| Melting Point[35] [K (°C)] | Casting T [K (°C)] | Nominal Compositions (Wt Pct) | ICP-OES Trace Analysis (Wt ppm) | Master Alloys/Materials (Wt Pct) | Macrostructure | |
---|---|---|---|---|---|---|---|---|---|
31 | B + P[17] | B2O3
| 2.55 | 723 (450) | 1423 (1150) | 0.170B, 0.0690P | 262B, 260P | CET excessive equiaxed grain coarsening | |
32 | B + P + Ag[18] | 1403 (1130) | 0.1B, 0.039P, 0.015Ag | Ag (99.9) | CET excessive equiaxed grain coarsening | ||||
33 | Mg + P[17] | MgO | 3.6 | 3098 (2825) | 1423 (1150) | 0.085Mg, 0.03P | 754Mg, 218P | large columnar | |
34 | Mg + P + Ag[18] | 1403 (1130) | 0.1Mg, 0.039P, 0.015Ag | CET excessive equiaxed grain coarsening | |||||
35 | Ca + P[17] | CaO | 3.34 | 3171 (2898) | 1423 (1150) | 0.085Ca, 0.03P | 448Ca, 264P | large columnar | |
36 | Ca + P + Ag[18] | 1403 (1130) | 0.1Ca, 0.039P, 0.015Ag | 547Ca, 390P, 145Ag | CET to a lesser extent | ||||
37 | Zr + P[17] | ZrO2
| 5.68 | 2982 (2709) | 1423 (1150) | 0.085Zr, 0.03P | 166Zr, 250P | large columnar | |
38 | Zr + P + Ag | 1403 (1130) | 0.15Zr, 0.04P, 0.015Ag | 1107Zr*, 360P, 96Ag | CET to a lesser extent | ||||
39 | Ti + P[17] | TiO2
| 4.95 | 2023 (1750) | 1423 (1150) | 0.085Ti, 0.039P | 16Ti, 305P | CET to a lesser extent | |
40 | Ti + P + Ag | 1423 (1150) | 0.116Ti, 0.04P, 0.0203Ag*
| 955Ti, 399P, 184Ag*
| CET to a lesser extent | ||||
41 | Sn + P + Ag | SnO, SnO3
| 6.45 6.85 | 1353 (1080), 1903 (1630) | 1423 (1150) | 0.1Sn, 0.039P, 0.015Ag | CET | ||
42 | Ge + P + Ag | GeO2
| 4.25 | 1388 (1115) | 1423 (1150) | 0.085Ge, 0.039P, 0.015Ag | 831Ge, 283P, 145Ag | Ge–[0.1-0.5] Ga (99.999 metal basis) | CET |
43 44 | Mn + P + Ag | MnO, Mn2O3
| 5.37 5.0 | 2112 (1839), 1353 (1080) | 1423 (1150) 1403 (1130) | 0.1Mn, 0.039P, 0.015Ag 0.1Mn, 0.039P, 0.015Ag | 308Mn, 350P, 143Ag | 99.7min.Mn-0.04max.C-0.05max.S- 0.005max.P-0.205max.Fe + Si + Se | large columnar CET to a lesser extent |
45 | In + P + Ag | In2O3
| 7.18 | 2185 (1912) | 1423 (1150) | 0.1In, 0.039P, 0.015Ag | In (99.99) | CET to a lesser extent | |
46 | 1403 (1130) | 0.1In, 0.039P, 0.015Ag | 953In, 309P, 123Ag | CET | |||||
47 | Ni + P | NiO | 6.72 | 2228 (1955) | 1423 (1150) | 0.092Ni, 0.03P | 773Ni, 274P, 41Fe, 20Mn | Cu-31Ni-1Mn-0.7Fe | columnar |
48 | Fe + P + Ag | Fe2O3, Fe3O4
| 5.25 5.17 | 1838 (1565), 1870 (1597) | 1423 (1150) | 0.721Fe, 0.039P, 0.015Ag | 643Fe, 300P, 138Ag | Cu-10.2Fe-0.08Pb-0.01Sn-0.02Mn-0.02Zn-0.005Al-0.005Si | CET to a lesser extent |
49 | 1403 (1130) | 0.1Fe, 0.039P, 0.015Ag | 0.02Mn-0.02Zn-0.005Al-0.005Si | CET to a lesser extent | |||||
50 | Zn + P + Ag | ZnO | 5.6 | 2247 (1974) | 1423 (1150) | 0.1Zn, 0.039P, 0.015Ag | Zn (99.9) | large columnar | |
51 | 1403 (1130) | 0.108Zn, 0.04P, 0.015Ag | 966Zn, 400P, 131Ag | CET to a lesser extent | |||||
52 | Al + P + Ag | Al2O3
| 3.97 | 2326 (2053) | 1423 (1150) | 0.1Al, 0.039P, 0.015Ag | 917Al, 390P, 112Ag | Al (99.99) | large columnar |