Abstract A process for the electrochemical removal of a metal cover wherein the electrically nonconductive underlying material to be exposed cannot withstand elevated temperatures produced by hot spots or arcs in the material being removed. The item to be processed is first masked, completely covering the area which is to be in contact with the etching solution. Segments of protective maskant are then removed in strips of prescribed width and at specified time intervals to expose additional material. The sequence produces graduated depths in the material being etched away and eventually results in the underlying material being exposed in incremental strips. Appropriate selection of timing and exposure width retains adequate unmasked covering material to avoid local areas of high current density, while insuring a smoothly expanding etched exposure of the underlying material.
A process for removing a metallic cover from an underlying nonconductive ignitible solid material comprising: a. coating the cover with a maskant; b. successively removing at regular intervals adjacent elemental areas of the maskant to incrementally expose the cover; and c. electrochemically removing a thickness of metal from the total exposed area of said cover during each interval that does not exceed a small fraction of the initial cover thickness.
Claim 2
Dependent Claim
70 words
A process for removing a metallic cover from an underlying nonconductive ignitible solid material comprising: a. coating the cover with a maskant; b. successively removing at regular intervals adjacent elemental areas of the maskant to incrementally expose the cover; and c. electrochemically removing a thickness of metal from the total exposed area of said cover during each interval that does not exceed a small fraction of the initial cover thickness.
Claim 3
Dependent Claim
36 words
The process of claim 1 in which said cover is the cylindrical case of a rocket motor, said material is the rocket propellant, and said elemental areas are strips around the circumference of the motor case.