Abstract: Methods and systems are provided for filling surface pores of a cylinder inner surface coating with one or more fill materials to provide desired material and performance properties. In one example, a cylinder for an engine includes an inner surface including a coating having a plurality of surface pores, at least a portion of the plurality of surface pores filled with one or more fill materials, the one or more fill materials configured to decrease friction, increase tribofilm formation, adjust heat transfer, decrease material deposit, and/or decrease run-in duration.

Abstract: Methods and systems are provided for filling surface pores of a cylinder inner surface coating with one or more fill materials to provide desired material and performance properties. In one example, a cylinder for an engine includes an inner surface including a coating having a plurality of surface pores, at least a portion of the plurality of surface pores filled with one or more fill materials, the one or more fill materials configured to decrease friction, increase tribofilm formation, adjust heat transfer, decrease material deposit, and/or decrease run-in duration.

Abstract: 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.

Abstract: 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.

Abstract: 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 wells for lubricant.

Abstract: Methods of honing a surface are disclosed. The method may include spraying a coating having an initial average bulk porosity onto an engine bore wall and honing the coating to create an intermediate honed surface. The method may then include cleaning the intermediate honed surface and honing the intermediate honed surface with a cutting force of, for example, 110-130 kgf after the cleaning step. This may create a honed surface having an average porosity greater than the initial average bulk porosity. The methods may create a honed surface having a porosity that is more porous than the initially sprayed coating. The increased porosity of the honed surface may allow for increased oil retention in, for example, engine bores.

Abstract: A method includes spraying a coating on to an engine bore surface, honing the coated surface to create a honed surface region, and cleaning the honed surface region to remove material from the surface pores. The honed surface region includes a plurality of surface pores and upper, middle, and lower regions. Cleaning the honed surface region produces upper, middle, and lower region surface porosities, with the middle region porosity being greater than at least one of the upper and lower porosities.

Abstract: A method includes spraying a coating on to an engine bore surface, honing the coated surface to create a honed surface region, and cleaning the honed surface region to remove material from the surface pores. The honed surface region includes a plurality of surface pores and upper, middle, and lower regions. Cleaning the honed surface region produces upper, middle, and lower region surface porosities, with the middle region porosity being greater than at least one of the upper and lower porosities.

Abstract: Methods of honing a surface are disclosed. The method may include spraying a coating having an initial average bulk porosity onto an engine bore wall and honing the coating to create an intermediate honed surface. The method may then include cleaning the intermediate honed surface and honing the intermediate honed surface with a cutting force of, for example, 110-130 kgf after the cleaning step. This may create a honed surface having an average porosity greater than the initial average bulk porosity. The methods may create a honed surface having a porosity that is more porous than the initially sprayed coating. The increased porosity of the honed surface may allow for increased oil retention in, for example, engine bores.

Abstract: 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 wells for lubricant.