Cylinder liner with its inner peropheral surface formed with surface treatment layer, and method for machining to the surface treatment layer

摘要

A cylinder liner for use in an internal combustion engine has an inner peripheral surface at which a surface treatment layer is formed upon water vapor treatment. The surface treatment layer has a surface configuration capable of providing excellent lubrication oil retaining function and initial break-in property as well as capable of being machined easily. The treatment surface of the cylinder liner has a plateau configuration providing a surface roughness Rz of 0.8 to 5.9 mum, and the plateau configuration is defined under DIN4776 by a reduced peak height Rpk of not more than 0.64 mum, a core roughness depth Rk of 0.05 to 1.8 mum, and a reduced valley depth Rvk of 0.15 to 3.3 mum. For grinding to the surface, a honing machine employs a grindstone containing metal bonded diamond grains at high density. Diamond grain size is not less than 4000.