Iron-based powder metallurgy self-lubricating CNG engine valve seat ring high in tensile strength and manufacturing method thereof

Abstract

The invention discloses an iron-based powder metallurgy self-lubricating CNG engine valve seat ring high in tensile strength. The iron-based powder metallurgy self-lubricating CNG engine valve seat ring is prepared from, by weight, 6.3-6.5 parts of chrome, 4.3-4.5 parts of cobalt, 0.6-0.9 part of nickel, 1.6-1.9 parts of zirconium, 2.8-3.2 parts of vanadium, 15-18 parts of copper, 0.9-1.2 parts of nanometer molybdenum disulfide, 0.5-0.7 part of tungsten disulfide, 0.3-0.6 part of carbon nano tubes, 1-2 parts of silica fume, 0.1-0.3 part of sodium pyrosulfite, 1.6-1.8 parts of steel fibers, 3-4 parts of polyimide resin powder, 2-3 parts of micro wax powder and 66-69 parts of iron. According to the iron-based powder metallurgy self-lubricating CNG engine valve seat ring, a layer of copper film is laid on the surface of the modified nanometer molybdenum disulfide, the modified nanometer molybdenum disulfide coated with the copper film serves as a solid lubricating agent and is added into a base material, meanwhile, the tungsten disulfide, the zirconium, the vanadium and the like are added, the metal particle phase change is changed through sintering, cast infiltration and the hot treatment technique, and the obtained product is high in tensile strength and fatigue resistance, resistant to oxidation and low in cost.

Description

technical field [0001] The invention relates to the technical field of automobile engine accessories, in particular to an iron-based powder metallurgy self-lubricating CNG engine valve seat with high tensile strength and a manufacturing method thereof. Background technique [0002] Compressed natural gas (CNG), liquefied petroleum gas (LPG) and methanol as alternative fuels for internal combustion engines are effective ways to protect the environment and use energy rationally. my country is rich in natural gas resources, and its market prospect as a clean fuel for engines is huge. However, with the use of new energy sources, the operating conditions of auto parts, especially engine valve seat rings, will change, and new requirements are put forward for their materials. The intake and exhaust valve seat rings of CNG engines are important working parts to control gas intake and exhaust gas discharge. Under high temperature, they are subjected to the erosion of air flow and hi...

AI Technical Summary

Problems solved by technology

[0004] Because the valve seat ring has no oil lubrication in the working process, its weather resistance is poor, its service life is short, and its long-term wear resistance is poor. At present, there are few researches on the combination of adding hard particles, self-lubricating additives, etc. and adopting a new infiltration process.

In the literature, only the new process of infiltration is adopted, and the method is relatively single, and the obtained valve seat green body has poor toughness, poor cutting performance, low temperature resistance and short service life, etc.