Carburizing steel for oil nozzle valve body and preparation method of carburizing steel

Abstract

The invention provides carburizing steel for an oil nozzle valve body and a preparation method of the carburizing steel. The carburizing steel mainly comprises carbon, manganese, copper, chromium, nickel, sulphur, aluminum, nitrogen and niobium. The preparation method of the carburizing steel comprises the following steps of conducting preliminary smelting; conducting steel ladle refining; conducting continuous pouring; rolling a bar material or a wire material; and drawing the bar material or the wire material till the surface is glossy. The carburizing steel and the preparation method thereof have the beneficial effects that after annealing is conducted on the steel for the oil nozzle valve body, a nodulizing pearlitic structure is obtained; hardness carbide particles are fine and uniform in size, and the hardness ranges from 185 HBW to 210 HBW; cutting and trepanning machining of the oil nozzle valve body can be conducted conveniently; and meanwhile, a prepared structure is providedfor subsequent carburization and quenching heat treatment.

Description

technical field [0001] The invention relates to the technical field of manufacturing and processing of ferrous metal materials, in particular to a carburized steel used for a fuel injection nozzle valve body and a preparation method thereof. Background technique [0002] In 1892, Diesel invented the diesel engine. After more than a century and several generations of hard work, the diesel engine has developed rapidly. The "heart" of the diesel engine is the fuel injection nozzle of the fuel injection system. working conditions. Under the action of oil pressure ≥ 160Mpa, the needle valve in the valve body jumps up and down thousands of times per minute to achieve the purpose of supplying evenly atomized fuel. At the same time, it is affected by the working temperature of the cylinder. The head temperature of the body can reach 250 ~ 360 ℃, so the injector valve body should have high surface hardness, high wear resistance, good tempering resistance, excellent dimensional stab...

AI Technical Summary

Problems solved by technology

Its disadvantages are: the high content of chromium and nickel makes the material expensive, and at the same time, the machinability is poor and the processing efficiency is low. In order to reduce the amount of retained austenite, a complex heat treatment process needs to be implemented, the dimensional stability is poor, and the stability against tempering is unstable. Generally only tempered at about 200°C

Therefore, still can't adapt to internal combustion engine to high-speed supercharging, the needs of high-horsepower direction development

Images