Steel piston composite hear insulation coating and spraying technology thereof

Abstract

The invention relates to a steel piston composite hear insulation coating and a spraying technology thereof, and belongs to the technical field of material surface engineering. The steel piston composite hear insulation coating is a solid-state compound coating and includes a high-temperature anti-oxidation layer, a low heat conductivity coefficient heat insulation layer, and a high-temperature anti-corrosion layer, wherein the high-temperature anti-oxidation layer is a nano ceramics coating, the heat insulation coating is a solid polymer coating doped with zirconia low thermal conductivity nano powder, and the high-temperature anti-corrosion layer is an anti-corrosion solid polymer coating. According to the steel piston composite hear insulation coating and the spraying technology thereof, the high-temperature anti-oxidation coating is prepared by magnetic control sputtering, the obtained steel piston composite heat insulation coating can effectively prevent combustion heat in a cylinder from outward diffusing from a piston to an engine, the hear loss is reduced remarkably, the overall heat efficiency of the engine is improved, and the service life of the piston is prolonged.

Description

technical field [0001] The invention belongs to the technical field of material surface engineering, and in particular relates to a steel piston composite heat-insulating coating and a spraying process thereof. Background technique [0002] Most of the existing steel piston top surface and combustion chamber surface adopt plasma thermal spraying process, and low thermal conductivity ceramic materials (such as zirconia) are sprayed to form a thermal insulation coating, which prevents the combustion heat in the cylinder from diffusing out of the engine through the piston. However, at present, the ceramic insulation material directly sprayed on the top surface of the steel piston and the inner surface of the combustion chamber has limited bonding strength with the steel piston body material, uneven coating thickness, insufficient high-temperature oxidation resistance, and high-temperature corrosion resistance. The coating is easy to oxidize and peel off, and at the same time, i...

AI Technical Summary

Problems solved by technology

However, at present, the ceramic insulation material directly sprayed on the top surface of the steel piston and the inner surface of the combustion chamber has limited bonding strength with the steel piston body material, uneven coating thickness, insufficient high-temperature oxidation resistance, and high-temperature corrosion resistance. The layer is easy to oxidize and peel off, and at the same time, incompletely burned fuel oil and up-flowing engine oil can easily lead to corrosion failure of the coating

Due to the limitations of the plasma thermal spraying process, the spray gun cannot directly act on the throat and bottom of the piston combustion chamber, resulting in uneven thickness of the thermal insulation coating in each area of ​​the combustion chamber, which greatly reduces the thermal insulation effect of the steel piston, and the thermal load distribution is uneven It is easy to cause fatigue failure of the piston material and reduce the service life of the engine