CN104651856A - Carbonitriding heat treatment technology of bearing roller - Google Patents

Abstract

The invention relates to a carbonitriding heat treatment technology of a bearing roller. The technology comprises the steps of: a, loading a bearing outer ring, a bearing inner ring and a steel roller made of GCr15 into a salt bath furnace containing a nitrocarburizing agent, conducting nitrocarburizing treatment at 600-650 DEG C for 3-4 h and taking out; b, conducting air cooling and cleaning; c, placing the clean bearing outer ring, the bearing inner ring and steel roller in the salt bath furnace, heating to 840-860 DEG C, insulating for a period of time, taking out and cooling in an oil tank; d, after quenching, tempering the bearing outer ring, the bearing inner ring, and the steel roller into oil at 170-190 DEG C for 2 h; and e, finishing the bearing outer ring, the bearing inner ring, and the steel roller. GCr15 bearing steel subjected to low temperature carbonitriding quenching compound heat treatment can form a 900HV hardening layer on the surface of the workpiece, and the wear resistance is obviously superior to the hardness of the roller subjected to conventional heat treatment.

Description

A kind of thermal treatment process of bearing roller carbonitriding

Technical field

The invention belongs to technical field of heat treatment technology, be specially the thermal treatment process of a kind of GCr15 steel bearing roller carbonitriding.

Background technology

GCr15 bearing steel is the special steel manufacturing rolling bearing, uses extremely extensive in mechanical field.Bearing operationally, subjects high repeated stress, and between ball and lasso, contact area is very little simultaneously, and stress high concentration, not only has rotation during work, and the very big friction produced because of slip in addition.Therefore require that bearing steel must have uniform high rigidity and high-wearing feature, high elastic limit and contact fatigue strength, the hardening capacity of enough toughness, and have certain resistance to corrosion in air and lubricant.For a long time, GCr15 steel bearing adopts traditional quench hot and low-temperaturetempering technique always, thus makes can not be strengthened further and improve always the work-ing life of bearing.

Data is had to show, Germany of world Production of bearing power, Sweden and Japan, its brand bearing widespread use of producing sulfurizing technology, and at home, sulfurizing technology be also only applied to mould and require antistick to wear and tear component on, about the sulfurizing technology people being applied to bearing aspect also start to repay examination.Undoubtedly, utilize new sulfurizing technology will provide favourable condition for improving lay in work-ing life of bearing, but only unilaterally start with from sulfurizing technology and fundamentally can't solve the problem in work-ing life of bearing.

Summary of the invention

The object of the present invention is to provide a kind of thermal treatment process of bearing roller carbonitriding, be intended to solve short problem in bearing work-ing life.

To achieve these goals, the present invention takes following technical scheme to implement: a kind of thermal treatment process of bearing roller carbonitriding, and its processing step is as follows:

A, the inside and outside lasso of bearing be made up of GCr15 steel and steel ball rolling body are loaded in the salt bath furnace containing nitrocarburizing medium, through 600 ~ 650 DEG C and be incubated 3 ~ 4 hours ooze process altogether, then get;

Clean after b, air cooling;

C, by cleaning after the inside and outside lasso of bearing and steel ball rolling body insert in salt bath furnace, be heated to 840 ~ 860 DEG C, insulation for some time after takes out and put into oil sump cool;

D, the inside and outside lasso of bearing after quenching and steel ball rolling body to be inserted in the fluid of 170 ~ 190 DEG C tempering 2 hours;

E, again precision work is carried out to the inside and outside lasso of bearing and steel ball rolling body.

GCr15 bearing steel can make workpiece surface form the hardened layer of 0.5 ~ 1mm through low temperature carbonitriding quenching combined heat treatment by the present invention, the hardness of its hardened layer can reach more than 900HV, under identical tempering temperature, combined heat treatment hardness, apparently higher than conventional Heat Treatment hardness, improves the tempering resistance of hardened layer.Because martensite middle and high concentration nitrogen is to the solution strengthening effect of a phase, the rolling body hardness under making Carbonitriding quenching combined heat treatment wear resistance obviously be better than typical heat treat condition.

Embodiment

The present invention adopts following processing step:

A, the inside and outside lasso of bearing be made up of GCr15 steel and steel ball rolling body are loaded in the salt bath furnace containing nitrocarburizing medium, through 600 ~ 650 DEG C and be incubated 3 ~ 4 hours ooze process altogether, then get;

Clean after b, air cooling;

C, by cleaning after the inside and outside lasso of bearing and steel ball rolling body insert in salt bath furnace, be heated to 840 ~ 860 DEG C, insulation for some time after takes out and put into oil sump cool;

D, the inside and outside lasso of bearing after quenching and steel ball rolling body to be inserted in the fluid of 170 ~ 190 DEG C tempering 2 hours;

E, again precision work is carried out to the inside and outside lasso of bearing and steel ball rolling body.

GCr15 bearing steel can make workpiece surface form the hardened layer of 0.5 ~ 1mm through low temperature carbonitriding quenching combined heat treatment by the present invention, the hardness of its hardened layer can reach more than 900HV, under identical tempering temperature, combined heat treatment hardness, apparently higher than conventional Heat Treatment hardness, improves the tempering resistance of hardened layer.Because martensite middle and high concentration nitrogen is to the solution strengthening effect of a phase, the rolling body hardness under making Carbonitriding quenching combined heat treatment wear resistance obviously be better than typical heat treat condition.

Claims (1)

1. a thermal treatment process for bearing roller carbonitriding, its technology characteristics is as follows:

A, the inside and outside lasso of bearing be made up of GCr15 steel and steel ball rolling body are loaded in the salt bath furnace containing nitrocarburizing medium, through 600 ~ 650 DEG C and be incubated 3 ~ 4 hours ooze process altogether, then get;

Clean after b, air cooling;

C, by cleaning after the inside and outside lasso of bearing and steel ball rolling body insert in salt bath furnace, be heated to 840 ~ 860 DEG C, insulation for some time after takes out and put into oil sump cool;

D, the inside and outside lasso of bearing after quenching and steel ball rolling body to be inserted in the fluid of 170 ~ 190 DEG C tempering 2 hours;

E, again precision work is carried out to the inside and outside lasso of bearing and steel ball rolling body.