Patent ID: 7617805
Filing Date: 2009-11-17
Classification: B22D,F02F,Y10T

Abstract:
1. A cast iron cylinder liner for receipt in an internal combustion engine cylinder block having a water cooling jacket surrounding a portion of the cylinder liner to facilitate regulating the temperature of the cylinder liner, said cylinder liner, comprising: a cylinder liner wall having an inner surface providing a cylinder bore extending along a central axis for reciprocation of a piston against an axial portion of said inner surface and an outer surface opposite said axial portion, said outer surface having a hardened outer layer of purely martensitic microstructure for direct exposure to the water cooling jacket, wherein said inner surface and said outer surface define a wall thickness of said cylinder liner wall, said hardened outer layer having a hardened depth equal to 10 percent or less of said wall thickness, said hardened depth being greater than zero.