Hafnium iodide refining process conditions shown in Table 1, the hafnium arc melting process conditions are shown in Table 2, the electron beam melting hafnium parameters in Table 3.
Table 1 iodine refining process conditions 
Hot wire material | W or Hf |
Rough temperature / °C | 600 |
Hot wire temperature / °C | 1400~1600 |
Twin rod purity /% | Hf>99.9, C=0.20, O=0.01-0.04, N=0.001-0.004, Fe=0.003～0.08 |
Hardness HB | 170 |
Dissociation reaction |
|
Table 2 Process conditions of arc melting
Smelting method | Non-consumable electrode | Consumable electrode arc melting | Double arc melting | |
Non-consumable electrode 1 | Consumable electrode | |||
Electrode head | Tungsten or tungsten coated with 1% to 2% ThO2 has a diameter of 1.27 to 1.91 cm and a length of 1.91 to 3.81 cm embedded in a water-cooled copper electrode. | Hf | W | Hf |
crucible | An inner diameter of 10.16 ~ 12.7cm, water-cooled copper crucible disposed in advance some of the feedstock to a very small amount of magnesium | Inner diameter 10.16 ~ 12.7cm, water-cooled copper crucible | The inner diameter of 6.35cm is first plugged with the tip of the crucible at the bottom of the copper crucible. | The inner diameter is 10.16~12. 7cm |
Vacuum before filling with inert gas /kPa | 1.33×10 - 3 | (1.33~2)×10 - 3 | (1.33~2)×10 - 3 | (1.33~2)×10 - 3 |
atmosphere | 5He+1Ar | 1He+1Ar | 2He+1Ar | 1He+1Ar |
Total pressure / kPa | 101.3 | 16.88 | 101.3 | 16.88 |
Melting voltage / V | 48~50 | 30~35 | 38~42 | 30~35 |
Smelting current / kA | 1.0 to 1.1 | 2.8~2.9 | 1.2 to 1.8 | 2.3 to 2.5 |
Smelting speed /kg·h - 1 | 4.54 | 27.22 | 81.65 | |
Recovery rate/% | 97 | |||
铪 ingot hardness HB | 184 | 171 | ||
Table 3 铪 electron beam melting parameters
Material size / cm | 8.4 | |
铪 ingot diameter / cm | 8.4 | 11 |
Smelting times | 1 | 2 |
Melting vacuum / kPa | 1.33×10 - 5 | 1.07×10 - 5 |
Smelting power / kW | 46~48 | 58～60 |
铪 smelting speed / kg · h - 1 | 12~14 | 20~24 |
Cooling time / h | 2.5 | 3.5 |
1kg 铪 power consumption / kW · h | 3.4 to 4.0 | 2.5 to 3 |
Ingot rate /% | 92～94 | 96 |
The conditions for 铪 electron beam melting given by Thomas Thomas are:
Furnace power: 225 kW (with two oil diffusion pumps with a displacement of 34 m 3 /s).
铪 ingot diameter: 7.62 ~ 15.24cm
Melting degree of vacuum: ≥1.33×10 - 5 kPa
Melting voltage: 4000～12000V
Electron gun bombardment current: 0 ~ 15A
Monthly production capacity: 1814kg
The first stage of smelting: 4h, rapid melting of the slightly pressed sponge into a bismuth ingot, diameter 7.62cm, length 10.16cm;
The second stage of smelting: 6h, the re-melting of the bismuth ingot, to ensure a certain degree of superheat, the diameter is still 7.62cm;
The third stage of smelting: 1h, and then smelted into a bismuth ingot, the diameter of 10.16cm, length 5.08cm;
The impurity content of the electron beam melting crucible is shown in Table 4.
Table 4 Impurity content of electron beam melting crucible /10 - 6
element | raw material | Electron beam melting bismuth ingot | ||
top | bottom | top | bottom | |
Al | 60 | 75 | 25 | 25 |
B | 7 | 3 | 0.3 | 0.5 |
C | 30 | 30 | 30 | 30 |
Cd | 1 | 2 | 1 | 1 |
Co | 5 | 5 | 5 | 5 |
Cr | 40 | 50 | 20 | 20 |
Cu | 30 | 30 | 30 | 30 |
Fe | 110 | 140 | 50 | 50 |
Mg | 10 | 10 | 20 | 20 |
Mn | 10 | 10 | 10 | 10 |
Mo | 40 | 40 | 40 | 40 |
N | 35 | 63 | 28 | 35 |
O | 850 | 1100 | 298 | 266 |
Si | 200 | 200 | 70 | 70 |
Ti | 100 | 120 | 10 | 10 |
Zr | 2.2% | 2.1% | 1.8% | 1.4% |
Hardness HB | 188 | 171 | ||
WE Series Enclosures
WE Series Enclosures
wybox inc. , https://www.wybox-inc.com