Cylindrical internal surface processing method

摘要

A cylindrical internal surface processing method comprises forming a cylinder bore, roughening an upper section of the bore, depositing coating onto the bore, and machining a lower section of the bore and the coating. The forming of the cylinder bore includes forming the upper and lower sections with the lower section being axially spaced from the upper section and having an axial length greater than zero. The roughening creates a roughened surface such that a radially innermost edge of the roughened surface has an internal diameter smaller than an internal diameter of the lower section. The coating is deposited to cover the upper section and at least a portion of the lower section. The machining forms a tapered portion and a cylindrical portion, a radially outermost edge of the cylindrical portion having an internal diameter larger than that of a radially outermost edge of the roughened surface.

主权项

1. A cylindrical internal surface processing method comprising:
forming a cylinder bore in a cylinder block with the cylinder bore having a cylindrical internal surface including an upper section and a lower section, the lower section being axially spaced from the upper section and having an axial length greater than zero with respect to a central axis of the cylinder bore; roughening the upper section of the cylindrical internal surface to create a roughened surface such that a radially innermost edge of the roughened surface with respect to the central axis has an internal diameter smaller than an internal diameter of the lower section; depositing a thermally sprayed coating onto the cylindrical internal surface to cover the upper section and at least a portion of an axial length of the lower section after the roughening of the upper section; and machining the lower section and the thermally sprayed coating along the lower section to form a tapered portion and a cylindrical portion such that
the tapered portion extends from the cylindrical portion toward the upper section, anda radially outermost edge of the cylindrical portion has an internal diameter that is larger than an internal diameter of a radially outermost edge of the roughened surface with respect to the central axis.