Sprayforming bulk deposits of allotropic metal

摘要

Method of sprayforming bulk metal deposits that replicate a master pattern: (i) casting and solidifying ceramic about a master pattern to form a spraying pattern; (ii) after removing the spraying pattern from the master pattern, heating the ceramic spraying pattern to a sustained temperature to effect an isothermal diffusion dependent microstructural transformation; (iii) while in such heated condition, thermally spraying allotropic metal particles onto the heated spraying pattern to form a deposit having a bulk thickness, the particles impacting the spraying pattern, or previously deposited particles, at a temperature above the sustained temperature of the spraying pattern; (iv) holding the deposit on the heated spraying pattern sufficiently long enough to allow the particles of the deposit to undergo a diffusion reaction that relieves internal stresses due to deposition and solidification; and (v) thereafter gradually cooling the deposit to room temperature to produce a unitary article with essentially no distortion relative to the spraying pattern.