Micromechanical Properties of UHMWPE’S with Different Molecular Weights

Abstract:

Ultrahigh molecular weight polyethylene (UHMWPE) is used as a key component of total joint replacements (TJR) and its mechanical performance is one of the factors influencing TJR lifetime. Micromechanical properties of three model UHMWPE samples with different molecular weights were evaluated from both non-instrumented and instrumented microindentation hardness testing. The properties were correlated with molecular and supermolecular structure of the samples. We have demonstrated that molecular weight influenced the final micromechanical properties mostly indirectly – it changed the overall crystallinity, which strongly correlated with microhardness, indentation modulus, and also with the elastic part of the indentation work. Only microcreep was influenced predominantly by amorphous phase, in which the higher molecular weight resulted in higher amount of entanglements and slightly higher creep resistance.

• Periodical: Key Engineering Materials (Volume 784)
• Pages: 33-37
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.784.33
• Online since: October 2018
• Authors: Miroslav Slouf*, Sabina Krejcikova, Jirina Hromadkova, Helena Vlkova
• Keywords: Microindentation Hardness Testing, Semicrystalline Polymers, Vickers Microhardness

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