Enhancement of Bio corrosion Resistance of Magnesium Alloy by Hydroxyapatite based Coating

Abstract

Magnesium alloys are considered as potential biomaterial for replacement of damaged bones and other hard tissues inside the body, because of unique combination of biocompatibility alongside physical characteristics. However, corrosion is an issue associated with magnesium alloys which not only affects structural integrity and mechanical properties but also hinders their extensive application. Processing and properties enhancement of magnesium alloy is an emerging field of research. Therefore, this doctoral work is motivated to focus on the cutting-edge research pertaining to semisolid processing of AZ91 magnesium alloy. newlineThe present work has strongly involved in the studies related to solidification, microstructure and mechanical properties of cooling slope semisolid casted magnesium alloy. However, more specifically, the purpose of present research is to enhance corrosion resistance of semisolid casted and heat treated AZ91 Mg alloy by hydroxyapatite coating.Explicitly, slurry at 5 distinct delivery rates (0.015, 0.020, 0.025, 0.030, 0.035 kg/s) alongside 5 distinct delivery heights from cooling slope outlet (50, 100, 150, 200, and 250 mm) are delivered inside metal mould. Modest delivery rate 0.025 kg/s alongside height 150mm provides medium solidification besides better characteristics. Slight changed coolant delivery rate/height would reason shearing that causes inferior structural characteristics. Ultimately, favoured microstructure was realized at 0.025 kg/s delivery rate and 150mm delivery height. Correspondingly, improved mechanical behaviours realized for 0.025 kg/s delivery rate and 150mm delivery height. newlinePresent study comprehensively describes about the influence of water flow beneath slope on structural characteristics of casted AZ91 Mg alloy. Additionally, the influence of water temperature too was studied. Here, over the cooling slope, hot melt flows from top to bottom. Additionally, under the cooling slope, coolant water flows from bottom to top.