Carbonitriding heat treatment process method

Abstract

The invention belongs to the field of process technology and provides a carbonitriding heat treatment process method. The carbonitriding heat treatment process method comprises the steps that parts are cleaned for degreasing, and the parts are tied after being cleaned and then are hung on a special fixture; the parts are heated up to be 50 DEG C higher than the carbonitriding temperature before being put into a furnace, a mixed solution with the ratio of methylbenzene to ethyl alcohol being 3:1 is dripped into the furnace at the temperature of being 50 DEG C higher than the carbonitriding temperature, and the dripping speed is 80 drips / min-100 drips / min; the pressure in the furnace is maintained to be between 5 mm water column and 15 mm water column, the furnace temperature is gradually reduced to the carbonitriding temperature, and the time is no less than one hour; the parts are fed into the furnace, timing is started when the furnace temperature is returned to the carbonitriding temperature of 800 DEG C+ / -5 DEG C, heat preservation lasts for 35 min-45 min, the dripping speed of a formamide permeating agent is 100 drips / min-130 drips / min, and the pressure in the furnace is maintained to be 10 mm water column-30 mm water column; the parts are taken out from the furnace and subjected to quenching in a 10% saline solution; salt traces on the surfaces of the parts are cleaned away in hot water, and the parts are dried; and then the parts are subjected to tempering in a nitrate bath furnace within 4 hours.

Description

technical field [0001] The invention relates to a carbonitriding heat treatment process for steel parts, in particular to a carbonitriding heat treatment process for 15CrV material. Background technique [0002] Since the carbonitrided bushing parts are important parts of a certain type of aircraft control system, the parts are required to have high surface hardness, good wear resistance, and high impact resistance toughness, and the core of the parts must also have a certain degree of plasticity. Therefore, in order to meet the technical requirements of parts, the design adopts 15CrV material for processing. This material has good hardenability. The vanadium existing in the compound state in the material produces fine particles to form crystal nuclei of new phases, which can improve the tempering of steel. Stability and has its strong secondary hardening effect. Solid solution in ferrite has strong solid solution strengthening effect and grain refinement effect, so it can ...

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Problems solved by technology

Vanadium can also improve the creep and durable strength of steel through the dispersed distribution of fine carbide particles. High plasticity during cold deformation. However, due to the complicated heat treatment process of this material, there is no mature process specification in China.

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