Hollow nickel shapes by vapor deposition
A method and apparatus for producing a nickel shape or shell employs nickel vapor deposition onto the inside surface of a closed, multi-part mandrel. The closed multi-part mandrel eliminates the need for a separate deposition chamber and the nickel vapor deposition creates a nickel shell in the shape of the complete or multi-part partial mandrel internal surface resulting in a hollow or partially hollow nickel product.
1. A method of producing a nickel article by nickel vapor deposition, comprising the steps of: providing a hollow multi-part mandrel having interior wall portions defining at least a portion of the exterior surface of a nickel article to be produced; purging the hollow multi-part mandrel of oxygen; heating said multi-part mandrel interior wall portions to a temperature sufficient to deposit nickel thereon in the presence of nickel carbonyl vapor; passing nickel carbonyl vapor through the heated hollow multi-part mandrel to produce said nickel article; purging the interior of the nickel article and the multi-part mandrel of nickel carbonyl vapor; and removing the nickel article from the mandrel.
2. A method as claimed in claim 1 wherein the multi-part mandrel interior wall portions are heated to at least 165° C. in areas where it is desired to deposit nickel.
3. A method as claimed in claim 1 wherein the multi-part mandrel interior wall portions are not heated above 130° C. in areas where nickel is not desired to be deposited.
4. A method as claimed in claim 1 wherein portions of the multi-part mandrel interior wall portions are heated to different temperatures to obtain different wall thicknesses of deposited nickel in different areas of the nickel article.
5. A method as claimed in claim 1 and further comprising the step of mounting an additional component on the interior wall portions to be encapsulated in nickel during the deposition process.
6. A method as claimed in claim 1 wherein the nickel carbonyl gas is passed through the heated hollow multipart mandrel until the deposited nickel is at least 0.05 mm (0.002 inches) in thickness.
7. A method as claimed in claim 1 wherein the nickel carbonyl vapor is mixed with carbon monoxide to vary the hardness of the nickel deposited.
8. A method as claimed in claim 1 wherein the nickel carbonyl vapor is mixed with carbon monoxide to vary the deposition rate of the nickel deposited.
9. A method as claimed in claim 7 wherein the amount of carbon monoxide mixed with the nickel carbonyl vapor is varied during the deposition process.
10. A method as claimed in claim 1 wherein the temperature of the multi-part mandrel interior wall portions is set to produce a nickel deposition rate of about 025 mm (0.01 inches) per hour.
11. A method as claimed in claim 1 wherein the temperature of the multi-part mandrel interior wall portions is varied during the deposition process to vary the rate of deposition of nickel.
12. A method as claimed in claim 2 wherein portions of the multi-part mandrel interior wall portions are heated to different temperatures to obtain different wall thicknesses of deposited nickel in different areas of the nickel article.
13. A method as claimed in claim 8 wherein the amount of carbon monoxide mixed with the nickel carbonyl vapor is varied during the deposition process.