**Abstract**

In recent years, emerging requisite for advanced materials gave a path for hybrid composites. Magnesium metal matrix composites are gaining more interest and a better substitute for heavier steel, aluminium, titanium and even for plastic based materials. At present the AZ91 magnesium alloy is most widely in transport vehicle industry. However, the application of AZ91 magnesium alloys are limited due to several negative effects such as poor creep resistance, wear resistance and inferior corrosion resistance when it is exposed to atmospheric conditions. Future to improve the strength, better corrosion resistance and wear resistance are important for their extend applications of exciting alloy AZ91. The main objective of the present investigation is to achieve above mentioned properties. The AZ91 alloy was reinforced with titanium dioxide/0.5% graphene and with titanium/0.5% graphene in varying weight percentage (1%, 2%) by stir casting technique. These combinations are called hybrid metal matrix composite of materials such as AZ91 + 1%Ti +0.5% Gr (A1), AZ91 + 2% Ti +0.5% Gr (A2), AZ91 + 1%TiO2 + 0.5% Gr (B1) and AZ91 + 2%TiO2 + 0.5% Gr (B2) alloys. The following experiments such as tensile, compressive, hardness and wear tests have been carried out to find all the properties from the newly developed hybrid metal matrix composite of materials and compared with AZ91. Wear tests have been carried out by pin on disc tribometer for both dry and wet sliding condition under 20 N,40 N,60 N, and 80 N. The results indicated the AZ91–1%TiO2–0.5%Gr having high wear resistance compared to other three combinations as well as AZ91. The present experimental investigations of hybrid metal matrix composite of materials have wear resistance in the order of B1 > A2 > A1 > B2 > AZ91 and AZ91–2%TiO2– 0.5% Gr showed good tensile strength and hardness. The enhanced these properties were discussed in this paper.

**Keywords:** hybrid composites, titanium dioxide, titanium, graphene and Wear
