Stainless steel bearing material load under the action of the strain limit

Many structural materials under the action of load there is a strain limit, if more than the limit, after the discharge load can't completely returned to its original size. Bearing steel also has the characteristic in compression. Such that when the load bearing of the ball pressure on the ball path, again after discharge load, rolling path may leave an impression, the ball could be a 'platform' is both points. Deformation if the water long enough, will cause the vibration of the bearing is too large, also can cause considerable stress concentration. 9. 2 permanent deformation calculation, in fact, even in very light also produces tiny permanent deformation under load. In figure 9. 1 from literature [ 11, said the typical ball bearing in the roller contact surface along the rolling direction and lateral magnification figure 20. In figure 9. 2 is taken from literature [ 1] , shows a similar to honing and lapping surface characteristics of grinding groove on the surface of the isometric view. Worth pointing out that even very good finishing surface will appear 'convex peak' and 'four valley'. Obviously, the load distribution of rolling element and raceway 2 b - To the contact area, the average compressive stress is r = Q/A, but before that, the load distribution only in relatively small convex peak area, contact stress at this time to 2 め ク degrees than the big many. In this way, local area may be more than compress yield strength, how much will be two surface pressure in figure 9. 1 ball and raceway contact surface ( At high magnification) Gentle buffing. According to the conclusion of Palmgren2, due to the deformation is too small, so the phenomenon of pressing for a little effects on the operation of the bearing. Light reflected from the surface of the slight change can be aware of this change. Chinese style (in chapter 6 6 - 43) Has been given, two steel objects of point contact elastic approach for 8 = 2. 79×1080( 2 p) Describe curve, and on any load deformation is large ( See figure deformation gradually deviate from the type began to deviate from the corresponding is the volume of the compressive yield strength. For degrees for 63. 5 - 65. 5 HRC high-quality bearing steel, base on the experimental data, Palmer, put forward the following contacts water meter sexual pressure formula of deformation of long = 1. 3×10 pn +点) ( pn+pn) ( 9 elastic pressure increase D type, P1 is curvature of the objects in the plane 1 and so on. For the ball and play way contact, type ( 9. 1) 8 = 5. 25 x10 - Q1Y( 9. 2) In figure 9. 3 point contact relation of deformation and load, the operator is used for inner raceway contact, the operator is used to outer raceway contact below. For liquid and play way point, get the following formula 8. = 5. 25×10( 9. 3) DIITY/R type, R for roller radius of bus wheel lang, R for groove curvature radius. The above formula for steel in compression elastic limit ( Fold point) The water near the long deformation calculation. See example 9. 1. For line contact roller and raceway, under the condition of the same as the front of the elastic limit, can use the following formula for calculating the deformation of 6 water long. 03×10( 奥( 9. 4) 1) 1 y according to Lundberg2 and others research results, when the raceway length exceeds the roller effective length, by type ( 9. 4) Calculation of deformation in the end of contact online.