Tribological behavior of ultra-high molecular weight polyethylene in a hip joint simulator

Abstract

In this paper effects of various injection molding parameters on tribological properties of ultra-high molecular weight polyethylene (UHMWPE) were investigated. The tribological properties like coefficient of friction and wear rate were obtained from the experimental results of hip simulator which was designed and fabricated in the laboratory. Bovine serum was used as a lubricant in this study. In addition, the hardness of the specimen was also investigated as well. The injection molding parameters that varied for this study are melt temperature, injection velocity and compaction time. The results show that contact loads and melt temperature were mostly influenced the tribological behavior of UHMWPE. A wear mechanism map was developed to study the dominant wear mechanism that influences the wear behavior of UHMWPE. SEM was employed to study the worn out morphologies of UHMWPE. The dominant wear mechanisms that are dominated through our study are ironing, scratching, ploughing, plastic deformation, and fatigue wear.

Keywords

UHMWPE / injection molding parameter / wear / tribological property / hip simulator

References

[1] BomBac D, Brojan M, Fajfar P, . Review of materials in medical applications. Materials and Geoenvironment , 2007, 54: 471-499
[2] Croop Brian, Lobo H. Mechanical and visco-elastic properties of UHMWPE for in-vivo applications. SPE European Conference on Medical Polymers , 2010
[3] Rezaei M, Ebrahimi N G, Shirzad A. Study on mechanical properties of UHMWPE/PET composites using robust design. Iranian Polymer Journal , 2006, 15(1): 3-12
[4] Fouad H, Mourad A H I, Barton D C. Effect of pre-heat treatment on the static and dynamic thermo-mechanical properties of ultra-high molecular weight polyethylene. Polymer Testing , 2005, 24(5): 549-556
[5] Schwartz C J, Bahadur S, Mallapragada S K. Effect of crosslinking and Pt-Zr quasicrystal ?llers on the mechanical properties and wear resistance of UHMWPE for use in arti?cial joints. Wear , 2007, 263(7-12): 1072-1080
[6] Wang S, Ge S. The mechanical property and tribological behavior of UHMWPE. Effect of molding pressure. Wear , 2007, 263(7-12): 949-956
[7] Kuo H-C, Jeng M-C. Effects of part geometry and injection molding conditions on the tensile properties of ultra-high molecular weight polyethylene polymer. Materials & Design , 2010, 31(2): 884-893
[8] Kuo H-C, Jeng M-C. The influence of injection molding on tribological characteristics of ultra-high molecular weight polyethylene under dry sliding. Wear , 2010, 268(5-6): 803-810
[9] Ge S, Wang S, Huang X. Increasing the wear resistance of UHMWPE acetabular cups by adding natural biocompatible particles. Wear , 2009, 267(5-8): 770-776
[10] Tretinnikov O N, Ogata S, Ikada Y. Surface cross-linking of polyethylene by electron beam irradiation in air. Polymer , 1998, 39(24): 6115-6120
[11] Xue Y, Wu W, Jacobs O, . Tribological behaviour of UHMWPE/HDPE blends reinforced with multi-wall carbon nanotubes. Polymer Testing , 2006, 25(2): 221-229
[12] Unal H, Mimaroglu A. Friction and wear behavior of un?lled engineering thermoplastics. Materials & Design , 2003, 24(3): 183-187
[13] Jeng M C, Fung C P, Li T C. The study on the tribological properties of ?ber-reinforced PBT composites for various injection molding process parameters. Wear , 2002, 252(11-12): 934-945
[14] Chand N, Dwivedi U K, Sharma M K. Development and tribological behaviour of UHMWPE ?lled epoxy gradient composites. Wear , 2007, 262(1-2): 184-190
[15] Williams J A. Wear modelling: analytical, computational and mapping: a continuum mechanics approach. Wear , 1999, 225-229: 1-17
[16] Srinivasan V, Karthikeyan R, Ganesan G, . Comparative study on the wear behavior of long and short glass fiber reinforced plastics. Metals and Materials International , 2010, 16(2): 205-212
[17] Ge S, Wang S, Gitis N, . Wear behavior and wear debris distribution of UHMWPE against Si₃N₄ ball in bidirectional sliding. Wear , 2008, 264(7-8): 571-578