SURFACE MODIFICATION ON THE STEM OF A TOTAL HIP JOINT REPLACEMENT
INTRODUCTION
Titanium and its alloys are used in various applications due to their desirable properties. One of the main sectors where titanium is highly used is in biomedical applications where both implants and tools for surgery make use of this element due to its biocompatibility, low modulus and excellent corrosion resistance. However titanium shows poor tribological properties and therefore it is generally alloyed and undergoes a surface modification to obtain the optimum requirements needed. Biomedical implants are subjected to high clinical requirements, hence before implantation in the human body, a surface modification process is carried out. The aim of carrying such modifications include; to sterilize the implant surface form contaminants before implantation, to increase the bioactivity, increase hardness and hence promotes the reduction in the implant wear rate and the introduction of a passive layer to minimize the ion release in the body.1
For this scope of this assignment a study in the surface modification of a titanium alloy stem, used in a hip joint implant is going to be studied. A total hip joint implant consists of an articulating bearing basically the femoral head and cup and the stem. The stem is made from titanium alloy - Ti- 6Al- 4V where titanium is alloyed with aluminium and vanadium. When titanium is alloyed with these materials excellent properties are achieved such as high strength-to-weight ratio and exceptional corrosion resistance.2 However, this alloy gives poor tribological properties and tends to seize when it is subjected to sliding motion due to its low hardness of 36HRC.3 Several surface modification techniques are done on ti...
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... The advanced technology of surface modification in the biomedical sector have the ability to offer not an improvement in the tribological properties only but also to improve the clinical requirements prior and post implantation. Such properties includes cell growth and antibacterial effect.
1-(pg4 doc.pdf)
2-http://www.arcam.com/wp-content/uploads/Arcam-Ti6Al4V-Titanium-Alloy.pdf
3- (reference ta lpdf twil)
4- http://www.news-medical.net/whitepaper/20130903/Hydroxyapatite-Coating-for-Titanium-Implants.aspx
Table 1 ghandek min http://www.azom.com/properties.aspx?ArticleID=1547 u l-pdf hi twil
5- http://emedicine.medscape.com/article/2085501-overview
6-http://www.intechopen.com/books/titanium-alloys-towards-achieving-enhanced-properties-for-diversified-applications/surface-modification-techniques-for-biomedical-grade-of-titanium-alloys-oxidation-carburization-and-
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