Sultan, Taimur  <br/><br/>
Synthesis and Characterization of Hydroxyapatite-Alumina biocomposite fabricated by Powder Metallurgy / 
Taimur Sultan 
 - 92p.  Soft Copy  30cm 
<br/><br/> Hydroxyapatite (HAP) is a very promising bio-ceramic as it resembles the mineral composition<br/>of bones and has excellent capability of bonding to bone tissues. It offers high biocompatibility,<br/>nontoxicity and good osteoconductivity. Therefore, it is an excellent choice for use as a bone<br/>substitute and in orthopedic or dental implants etc. However, its use is limited in biomedical<br/>applications specifically load-bearing implants as HAP exhibits poor mechanical properties.<br/>Alumina, known for its excellent mechanical strength and chemical stability, is added in HAP<br/>to enhance the mechanical properties of the composite while maintaining biocompatibility. The<br/>objective of this research is to synthesize and characterize a modified bio-composite with<br/>enhanced mechanical properties and excellent biocompatibility. For this purpose, an AluminaHAP bio-composite is developed with varying weight percent (wt. %) of Alumina. Two<br/>different processing routes, planetary ball mill which is high energy ball milling (HEBM) and<br/>tumbler ball milling i.e. low energy ball milling (LEBM), are adopted to mix the powders, and<br/>their impact on the mechanical properties is studied. The samples were prepared by using<br/>powder metallurgy techniques such as cold compaction followed by high temperature vacuum<br/>sintering process. The microstructure analysis is carried out using characterization techniques<br/>such as XRD, SEM etc. Mechanical testing of the samples is performed to compare the<br/>mechanical properties including density, hardness and compression strength of the sintered<br/>samples. The experimental results indicate that mechanical alloying using high-energy ball<br/>milling technique has significantly improved mechanical properties. Moreover, the mechanical<br/>properties of the bio-composite enhance with addition of Alumina (Al2O3) with the best results<br/>found for composite consisting of 40%HAP-60%Alumina. Overall, this research contributes<br/>towards the understanding of bio-composite materials for biomedical applications and the<br/>potential of HAP-Alumina bio-composite developed via Powder Metallurgy as a promising<br/>material for orthopedic and dental applications. 
<br/><br/><label>Subjects--Topical Terms: </label><br/>MS Mechanical Engineering      
<br/><br/><label>Dewey Class. No.: </label>621