Finite element analysis of the effects of additional load phase and amplitude on fretting wear

Author(s):  
Ling Li ◽  
Shiyun Ma ◽  
Zhiqiang Li ◽  
Xiaoguang Ruan

Fretting wear is a major form of fretting damage involving various factors, such as material properties, surface roughness, surface topography, lubrication conditions, environment temperature, type of loading, and loading phase difference. In this study, ABAQUS is used to establish three models to simulate the variation of wear depth with the amplitude of additional load. The influence of the phase difference between additional load and original load is considered. Four phase difference angles are involved, i.e. 0°, 90°, 180°, and 270°. Results indicate that the rule of the variation of wear depth with the additional load amplitude increasing varies under different phase differences. It is observed that for the 0° phase difference, the wear depth firstly decreases then increases with the increase of the additional load. However, the wear depth increases monotonously in the case of the 180° phase difference. The variation of wear depth with additional load amplitude for 90° phase difference is similar to that of the 270° phase difference. The depth of wear is firstly kept at a relatively low level and then increases sharply, with the increase of the additional load. It is found that the distribution of shear stress and relative slip at the contact interface is also affected by the phase difference.

Author(s):  
Ling Li ◽  
Ziming Wei ◽  
Dong Zhang ◽  
Jingjing Wang ◽  
Xiaohui Shi

Fretting fatigue is a major form of fretting damage affected by various factors. In this paper, the Ruiz parameter is used to predict the variation in the initiation location of the fretting fatigue crack with the amplitude of load, providing a reference for the study of the initiation characteristics of fretting fatigue cracks. The influence of the phase difference between loads is also considered. Three numerical models are established using ABAQUS for simulation experiments. Four phase difference angles are involved, i.e. 0°, 90°, 180° and 270°. Results indicate that for 0° phase difference, the maximum of initiation parameter K is always observed at the trailing edge of the contact zone (near the loading side of the strain load) with the increase of load amplitude, such that the fretting fatigue crack initiates at the trailing edge. However, for 90°, 180°, and 270° phase differences, the maximum of initiation parameter K shifts from one edge of the contact to the other with the increase of load amplitude. In addition, it is observed that the maximum and minimum initiation parameter K values are obtained for 0° and 180° phase differences, respectively, while the values of K for 90° and 270° phase differences are approximately equal and between those for 0° and 180°.


2020 ◽  
Vol 12 (5) ◽  
pp. 168781402091922
Author(s):  
Zhipeng Lyu ◽  
Fuyuan Wang ◽  
Sizhu Zhou ◽  
Si Liu

In order to study fretting wear damage law of planetary frame axle hole, the distribution of normal stress and relative sliding velocity at axle hole was obtained by finite element software, and a method of extracting fretting wear characteristic parameter data was put forward and verified. According to the modified model of fretting wear depth calculation, the wear depth of each step at axle hole was calculated, and the influence of interference on wear depth was analyzed. The results show that the stress distribution obtained by this method corresponds to the values of each node in the Workbench stress nephogram at that time and has the same distribution rule, which shows that the method is correct. The stress concentration near the inner part of the axle hole of the planetary frame is obvious. Along the circumferential and axial direction of the shaft hole, the relative slip velocity of both ends is larger, and the relative slip velocity of the middle part is smaller. Average wear in both axial and circumferential directions increases with the increase in interference, while wear in the axial direction plays a dominant role in the whole meshing process.


2018 ◽  
Vol 32 (19) ◽  
pp. 1840055 ◽  
Author(s):  
Jong Seok Kim ◽  
Yeong Min Park ◽  
Sang Yoon Kim ◽  
Mun Ki Bae ◽  
Dong Qi ◽  
...  

Fretting occurs at the contact area between two materials under load and in the presence of minute relative surface motion by vibration or external force. Bearings, clutches, riveted and bolted lap joints are subjected to fretting damage. Friction coefficient, materials of the specimen, contact surface pressure, relative slip amplitudes, temperatures and environment have an effect on the fretting. In this study, fretting wear test is conducted with SCM415 (Cr–Mo alloy steel) which are much used for making gears and shafts because of its excellent machinability, good mechanical properties and low cost, compared with those of the existing machine structural steels. In order to determine the fretting wear type, fretting wear fixture which can be attached to the servo hydraulic fatigue testing machine is made. And then, specimens and fretting pad with a constant curvature are made of SCM415 materials. Different normal forces and displacement amplitudes are applied to the fretting pad and diamond-like carbon (DLC) is coated on the fretting pad for fretting wear test.


2019 ◽  
Vol 2019 ◽  
pp. 1-6
Author(s):  
Davood Khodadad

We present a digital holographic method to increase height range measurement with a reduced phase ambiguity using a dual-directional illumination. Small changes in the angle of incident illumination introduce phase differences between the recorded complex fields. We decrease relative phase difference between the recorded complex fields 279 and 139 times by changing the angle of incident 0.5° and 1°, respectively. A two cent Euro coin edge groove is used to measure the shape. The groove depth is measured as ≈300  μm. Further, numerical refocusing and analysis of speckle displacements in two different planes are used to measure the depth without a use of phase unwrapping process.


2000 ◽  
Vol 123 (4) ◽  
pp. 686-698 ◽  
Author(s):  
K. Iyer ◽  
C. A. Rubin ◽  
G. T. Hahn

Primary fretting fatigue variables such as contact pressure, slip amplitude and bulk cyclic stresses, at and near the contact interface between the rivet shank and panel hole in a single rivet-row, 7075-T6 aluminum alloy lap joint are presented. Three-dimensional finite element analysis is applied to evaluate these and the effects of interference and clamping stresses on the values of the primary variables and other overall measures of fretting damage. Two rivet geometries, non-countersunk and countersunk, are considered. Comparison with previous evaluations of the fretting conditions in similar but two-dimensional connections indicates that out-of-plane movements and attending effects can have a significant impact on the fatigue life of riveted connections. Variations of the cyclic stress range and other proponents of crack initiation are found to peak at distinct locations along the hole-shank interface, making it possible to predict crack initiation locations and design for extended life.


2016 ◽  
Vol 139 (3) ◽  
Author(s):  
S. Boedo ◽  
S. A. Coots

This paper investigates the wear characteristics of a novel squeeze-film hip implant design. Key features of the design are elastic elements attached to the cup which provide a mechanical means for ball separation during the swing phase of the gait loading cycle. An Archard-based wear formulation was implemented utilizing the ansys finite element analysis program which relates contact pressure and sliding distance to linear wear depth. It is found that low-modulus elastic elements with bonded high-modulus metal coatings offer significant predicted improvement in linear and volumetric wear rates when compared with conventional implant geometries for gait cycle loading and kinematic conditions found in practice.


Author(s):  
Pankaj Dhaka ◽  
Raghu V. Prakash

Abstract Understanding the effect of load sequence is important in the context of a blade-disc dovetail joint in an aero-engine and many other such applications where, the mating surfaces undergo fretting wear under variable slip amplitude loading conditions. In the present work, a two-dimensional finite element analysis is carried out for a cylinder-on-plate configuration. The cylinder is modeled as deformable whereas the plate is modelled as rigid. An incremental wear modelling algorithm is used to model the wear of cylindrical pad while the plate is assumed as un-worn. This simulates a practical scenario where, generally one of the mating surfaces is sufficiently hardened or an interfacial harder/sacrificial element is inserted to restrict the wear to only one of the surfaces. A Fortran-based ABAQUS® subroutine UMESHMOTION is used to simulate the wear profile for the cylinder. A constant extrapolation technique is used to simulate 18000 cycles of fretting. The finite element analysis results are validated with the analytical solutions and literature data. The fretting wear modelling is carried out for two different slip amplitudes viz., 25 μm and 150 μm, to simulate the low and high slip amplitude loading respectively. Two blocks of alternate low and high slip amplitudes are applied to understand the influence of load sequence. Important contact parameters viz., contact pressure, contact stresses and contact slip are extracted. A comparison is made between the low-high and high-low load sequence based on the contact tractions and worn out profiles.


2021 ◽  
pp. 1-49
Author(s):  
Li Xiao ◽  
Yingqiang Xu ◽  
Zhiyong Chen

Abstract In this paper, a multi-layer body model in which material properties and wear coefficient change with node coordinates is proposed, so that the wear profile is not restricted by the singularity of the interface of the coated contact pairs. The conversion rate of the adhered particles was obtained to describe the growth and expansion of the debris at the fretting interface based on experiments, and the wear model of coated contact pair considering the dynamic evolution of the debris layer was established. By comparing the previous experimental and computational results, the wear calculation method proposed in this paper is more reasonable to predict the wear profile of the coated contact pair. In addition, the influence of the debris layer on the wear depth, friction width, and contact pressure in the fretting process is analyzed, indicating that the existence of the debris layer can delay the wear process. Finally, the fretting wear life of the SCMV steel contact pair deposited with the W-DLC coating is estimated.


2018 ◽  
Vol 141 (3) ◽  
Author(s):  
Huaidong Yang ◽  
Itzhak Green

This work employs a three-dimensional (3D) finite element analysis (FEA) to investigate the fretting metallic contact between a deformable hemisphere and a deformable flat block. Fretting is governed by displacement-controlled action where the materials of the two contacting bodies are set to have identical properties; studied first is steel-on-steel and then copper-on-copper. At contact onset, a normal interference (indentation) is applied, which is then followed by transverse cyclic oscillations. A large range of coefficients of friction (COFs) is imposed at the interface. The results show that the maximum von Mises stress is confined under the contacting surface for small COFs; however, that maximum reaches the contacting surface when the COFs are sufficiently large. It is also shown that fretting under sufficiently large COFs forms large plastic strains in “ring” like patterns at the contacting surfaces. Junction growth is found where the contacting region is being stretched in the direction of the fretting motion. At large COFs, pileups show up at the edges of the contact. The fretting loops of the initial cycles are found along with the total work invested into the system. At certain interference, there exists a certain COF, which results in the largest work consumption. The magnitude of the COF is found to produce either partial slip (prone for fretting fatigue) or gross slip (prone for fretting wear). A scheme of normalization is proposed, and it is shown to be effective for the two said materials that have vastly different material properties. Hence, the normalized results may well characterize a range of contact scales (from micro to macro) of various ductile material pairs that behave in an elastic–plastic manner with strain hardening.


Sign in / Sign up

Export Citation Format

Share Document