Metal gasket and process for manufacturing the same

摘要

A metal gasket comprising a least one gasket sheet, wherein a hardness lowering region having a locally lowered hardness is formed in the gasket sheet in at least either a portion to be set to have a large elongation or a portion to be lowered in a spring constant. Also disclosed is a metal gasket manufacturing process comprising: the step of forming an opening of a desired size in registration with a cylinder bore in an elastic metal sheet as a material for making a gasket sheet composing a metal gasket; the step of annealing a portion, as corresponding to the first hardness lowering region in the gasket sheet, of the elastic metal sheet; and the step of forming a folded portion by folding back the vicinity of the opening.