Seal formed out of a hard metal with a plating of soft metals

An improved seal for use in sealing a gas laser system which includes:

• a. an elongated cylindrical chamber which is formed from a ceramic material and which has an axis, a first open end and a flat circular peripheral edge adjacent to said first open end;
• b. a reflector mount which is a circular member having has a flat surface which is substantially coaxially aligned with said axis and which is disposed adjacent, but not contiguous, to said flat circular peripheral edge of said elongated cylindrical chamber;
• and
• c. coupling means for mechanically coupling said flat surface of said reflector mount to said first open end of said elongated cylindrical chamber wherein said improved seal is inserted between said flat surface of said circular member and said flat circular peripheral edge of said elongated cylindrical chamber and said coupling means applies a compressive force, said improved seal comprising:
• a. an annular member having an outer surface and being formed from titanium which is relatively non-deformable by said compressive force, said annular member having a substantially circular cross-section, said annular member also having a slot which is disposed orthogonally to said axis and adjacent to its outer peripheral edge;
• and
• b. a plating of gold which is mechanically coupled to said outer surface of said annular member wherein said plating of gold is deformable by said compressive force so that said plating of gold forms a seal between said flat surface of said circular member and said flat circular peripheral edge of said elongated cylindrical member whereby the coefficient of thermal expansion of titanium forming said annular member matches the coefficient of thermal expansion of the ceramic material forming said elongated cylindrical chamber.