Liquid metal printing
Liquid metals or plastic are deposited into a reservoir of powder that supports the liquid metal or plastic as it cools.
1. A method of forming a metal object, the method comprising:
a) depositing a liquid metal into a reservoir of powder by using an apparatus for extruding liquid metal, the apparatus comprising:
i) a crucible having an upper chamber with a well for holding liquid metal;
ii) a first heating element that at least partially surrounds the crucible;
iii) an interior chamber below the crucible that connects the crucible to a nozzle;
iv) an exterior chamber, having positioned therein a second heating element that at least partially surrounds the interior chamber; and
v) a rod disposed between the nozzle and a solenoid resting above the crucible; and
b) allowing the metal to solidify.
2. The method of claim 1 , further comprising moving the nozzle in three dimensions.
3. The method of claim 1 , wherein a gantry or robotic arm moves the nozzle.
4. The method of claim 1 , wherein the powder is powdered salt.
5. The method of claim 1 , wherein the liquid metal is deposited at least 55 mm below a surface of the powder.
6. The method of claim 1 , further comprising forming a joint by moving the nozzle through previously-deposited liquid metal.
7. The method of claim 1 , further comprising forming a joint by depositing liquid metal adjacent to previously deposited, but solidified metal.
8. An apparatus for extruding liquid metal, the apparatus comprising:
a) a crucible having an upper chamber with a well for holding liquid metal;
b) a first heating element that at least partially surrounds the crucible;
c) an interior chamber below the crucible that connects the crucible to a nozzle;
d) an exterior chamber, having positioned therein a second heating element that at least partially surrounds the interior chamber; and
e) a rod disposed between the nozzle and a solenoid resting above the crucible.
9. The apparatus of claim 8 , further comprising a probe positioned within the crucible and supported above the crucible, whereby the probe is configured to generate a signal indicative of the presence of an electrical current.
10. The apparatus of claim 8 , further comprising an inlet into the upper chamber for an inert gas.
11. The apparatus of claim 8 , further comprising a clamp that connects the interior chamber to a bracket.
12. The apparatus of claim 8 , wherein the nozzle and interior chamber have mating threaded portions.
13. The apparatus of claim 8 , further comprising a motor that controls inlet of feedstock wire into the crucible.
14. The method of claim 1 , wherein the liquid metal is aluminum.