Abstract
Modularity at the head-neck junction of hip implants may result in fretting wear and implant failure. Most previous studies have applied major simplifications to simulate this phenomenon at the taper junction (e.g. negligence of mismatch angle, simulation in dry condition).
In this study, a 3D model of a Co-28Cr-6Mo head-neck junction with a proximal mismatch angle was analysed under a walking gait loading, and the most critical section at the interface was identified (Fig. 1) and a 2D model was generated. The 2D model was then subjected to a cyclic gait loading for four million cycles to investigate fretting wear and quantify the amount of lost material. An ABAQUS user subroutine (UMESHMOTION) code was developed to apply the Archard wear model to contacting nodes through the adaptive meshing constraint framework (Fig. 2). This fretting wear model was verified by [1] (a pinon-disc fretting wear process). The model was developed to simulate the fretting wear in both air and a phosphate buffered saline (PBS) withe their relevant friction and wear coefficients. As shown in Fig. 3, rate of wear in air was significantly greater than the PBS (almost 10 times greater) indicating the significance of environment. Variations in contact pressure, contact length, and displacement of the neck were also investigated over the process. This model can be further used for different materials, geometries and loadings.
In this study, a 3D model of a Co-28Cr-6Mo head-neck junction with a proximal mismatch angle was analysed under a walking gait loading, and the most critical section at the interface was identified (Fig. 1) and a 2D model was generated. The 2D model was then subjected to a cyclic gait loading for four million cycles to investigate fretting wear and quantify the amount of lost material. An ABAQUS user subroutine (UMESHMOTION) code was developed to apply the Archard wear model to contacting nodes through the adaptive meshing constraint framework (Fig. 2). This fretting wear model was verified by [1] (a pinon-disc fretting wear process). The model was developed to simulate the fretting wear in both air and a phosphate buffered saline (PBS) withe their relevant friction and wear coefficients. As shown in Fig. 3, rate of wear in air was significantly greater than the PBS (almost 10 times greater) indicating the significance of environment. Variations in contact pressure, contact length, and displacement of the neck were also investigated over the process. This model can be further used for different materials, geometries and loadings.
| Original language | English |
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| Publication status | Published - 2016 |
| Event | 3rd International Conference on BioTribology - Imperial College London, London, United Kingdom Duration: 11 Sep 2016 → 14 Sep 2016 Conference number: 2016 |
Conference
| Conference | 3rd International Conference on BioTribology |
|---|---|
| Abbreviated title | ICoBT |
| Country/Territory | United Kingdom |
| City | London |
| Period | 11/09/16 → 14/09/16 |
| Other | Biotribology plays an important role in many aspects of our everyday life from artificial joint implants and “mouth-feel” of food texture to hair conditioners and contact lens comfort. It is a multidisciplinary field which includes aspects of biology, surface physics, materials, chemistry, biomechanics and mechanical engineering. The aim of the ICoBT meetings therefore is to bring together researchers from across the scientific and engineering spectrum, to promote communication across the different disciplines and to provide a platform for the presentation of new work in one meeting focussed solely on Biotribology. |