Numerical Simulation Of Dual-Rotary Fretting Contact Based On ABAQUS

Fretting phenomena in actual engineering application are usually extremely complicated. The relative motion modes are not only simple tangential, radial, rotational or torsional fretting. The pattern that is combined with two or more basic modes is more likely to be happened. Up to the present, the studies have focused on the tangential mode. However, the composite mode has been little studied in previous researches. Dual rotary fretting is combined with torsional and rotary fretting, which is the direct reasons for some failures of many rotary components. Therefore, Study on the numerical simulation for dual rotary fretting is significantly important for basic theory and engineering applicationBased on the experimental studies, a three-dimensional ball (GCr15 steel)-on-flat (LZ50 steel) elastic-plastic contact finite element model has been established in ABAQUS software in this paper. The dual-rotary fretting mode in contact of ball-on-flat can be achieved by changing the tilt angle between the normal-direction of flat specimen and the rotary axis of the ball. The effect of tilt angles and angular displacement on many key parameters of fretting such as contact pressure, relative slip distance, dynamic curves, plastic accumulated strain and contact status is investigated in details. The numerical simulation results have been verified by experiment data, and the main conclusions are listed as follows:1. Under a status of gross slip, the angular displacement decreased with the increase of the tilt angle which accorded with the law of that the quadratic sum of normalized rotational and torsional components equals one.2. The stress distributions of contact interfaces were strongly dependent upon the tilt angle. To compare with the simple mode of torsional or rotational fretting, the damage of dual-fretting presented an asymmetrical distribution obviously3. With the increase of tilt angle, the plastic strain of one side was gradually vanished, and with the increase of the angular displacement, it appeared again. The Plastic accumulated strain increased slowly when both of the angular displacement and tilt angle were lower, if both of the angular displacement and tilt angle were higher, a reverse result can be obtained, and the plastic accumulated strain reached stable state quickly.4. Under reverse loading condition, the contact status presented a different evolution, the contact status in dual rotary fretting can be divided into two types:1) The First status:sticking zone shrank or enlarged around a certain point as the center.2) The second status:under reversed loading, the sticking zone appeared abruptly at the other side, and then it returned back to the original side with the increase of angular displacement, so repeated.