Cylinder bore having variable coating

• Main Authors: Maki, Clifford E, Beyer, Timothy George, Elie, Larry Dean, Gangopadhyay, Arup Kumar, Boileau, James Maurice, Ghaednia, Hamed
• Format: Patent
• Language: English
• Published: 18.08.2020
• Subjects: APPLYING LIQUIDS OR OTHER FLUENT MATERIALS TO SURFACES, IN GENERAL; ARRANGEMENTS OF SEALINGS IN COMBUSTION ENGINES; BLASTING; CHEMICAL SURFACE TREATMENT; CHEMISTRY; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATIONOR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY IONIMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; COATING MATERIAL WITH METALLIC MATERIAL; COATING METALLIC MATERIAL; COMBUSTION ENGINES; CYLINDERS, PISTONS OR CASINGS, FOR COMBUSTION ENGINES; DIFFUSION TREATMENT OF METALLIC MATERIAL; HEATING; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION INGENERAL; LIGHTING; MECHANICAL ENGINEERING; METALLURGY; PERFORMING OPERATIONS; PROCESSES FOR APPLYING LIQUIDS OR OTHER FLUENT MATERIALS TOSURFACES, IN GENERAL; SPRAYING OR ATOMISING IN GENERAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THESURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; TRANSPORTING; WEAPONS

Engine blocks and methods of forming the same are disclosed. The engine block may comprise a body including at least one cylindrical engine bore wall having a longitudinal axis and including a coating extending along the longitudinal axis and having a coating thickness. The coating may have a middle region and first and second end regions, and a plurality of pores may be dispersed within the coating thickness. The middle region may have a different average porosity than one or both of the end regions. The method may include spraying a first porosity coating in a middle longitudinal region of the bore and spraying a second porosity coating in one or more end regions of the bore. The first porosity may be greater than the second porosity and the first and second porosities may be formed during the spraying steps. The pores may act as wells for lubricant.