Thermally applied coating of mechanically alloyed powders for piston rings
AssigneeFederal-Mogul Burscheid GmbH
InventorChristian Herbst-Dederichs
Life of this patent
Estimating the term…
Abstract
The invention relates to a wear-resistant coating used for bearing surfaces and flanks of piston rings in internal combustion engines. The wear-resistant inventive coating is obtained by mechanically alloying powders which form a metallic matrix with hard material dispersoids and lubricant material dispersoids. The coating is then thermally applied to the workpieces, especially by means of high velocity oxygen fuel spraying (HVOF). The workpieces coated are bearing surfaces and parts of flanks pertaining to piston rings in internal combustion engines.
Claims13
A piston ring for internal combustion engines, said piston ring formed by the process of:
- providing a piston ring having at least one of a flank surface and a bearing surface,
- mechanically alloying a metallic matrix and a ceramic phase to provide a compound powder mixture for applying to said at least one of said flank surface and said bearing surface, wherein said metallic matrix is present in an amount of from 5 to 70% by volume and said ceramic phase is present in an amount of from 30 to 95% by volume, both relative to said total compound powder mixture,
- wherein said metallic matrix comprises at least one of nickel and iron and an alloying element selected from at least one of carbon, silicon, chromium, molybdenum, cobalt, nickel and iron, whereby said alloying elements do not exceed 70% by weight of said metallic matrix;
- and
- wherein said ceramic phase is selected from at least one of Al2O3, Cr2O3, TiO2, ZrO2, Fe3O4, TiC, SiC, CrC, WC, BC or diamond, and wherein said ceramic phase has a particle size of up to 10 μm, and
- thermal spraying said compound powder mixture to at least one of said flank surface and said bearing surface.
A wear-resistant coating for the bearing surfaces and flanks of piston rings comprising:
- a compound powder mixture comprising a metallic matrix and at least one ceramic phase mechanically alloyed with one another to form said compound powder mixture;
- said metallic matrix comprising at least one of nickel and iron and an alloying element selected from at least one of carbon, silicon, chromium, molybdenum, cobalt, iron, and nickel, whereby said alloying elements do not exceed 70% by weight of said metallic matrix;
- and
- said ceramic phase selected from Al2O3, Cr2O3, TiO2, ZrO2, Fe3O4, TiC, SiC, CrC, WC, BC or diamond and having a particle size of up to 10 μm;
- said alloying element present in an amount of from 5 to 70% by volume and said ceramic phase present in an amount of from 30 to 95% by volume, both relative to said total compound powder mixture;
- and
- wherein said compound powder mixture is applied by means of thermal spraying.
Dependencies are inferred from the claim text.