To save a manufacturing expense of combining with a coating material surely and reducing a necessary material amount and improve an engine operation.
A metal engine block 10 is casted and a pollutant is removed from a cast cylinder bore wall 11 and a powder mixture containing a solid lubricant particles having a dry friction coefficient of 0.3% or less along with a plasma sprayed coating 12 are deposited on the surface and the coating is shaped concentrically around the true axis 14 of the cylinder bore wall and honed 16 up to the smoothness of final finishing. The exposure of a fresh metal surface is carried out by a grit (shot) blasting, electric discharge erosion, mechanical cutting of serration or plasma etching. Concentric shaping is carried out either by rough machining the cylinder bore wall and followed by deposition of the thinnest coating that requires only finish honing or by deposition of a thick coating followed by rough honing.
ROBAATO ARAN ROOZU
KARURO ARUBERUTO FUASHINARI
