Effect of reinforcements on graphite/titania/aluminium nanohybrid composites

Aluminium alloys and their composites are often used in aerospace, automobile and biomedical applications. However, mechanical and surface properties of those alloys have not reached up to the expectation. This investigation focused to improve the wear resistance properties along with mechanical and surface properties of aluminium matrix composites. Here, novel aluminium matrix nanohybrid composites were developed using titanium oxide and graphite as reinforced via powder metallurgical route. The sintered samples were analysed by different tests such as, hardness, surface roughness, wear tests and other structural analyses. The obtained results showed that some new compounds formed during sintering were responsible for improved mechanical and surface properties for different applications. The wear test showed that there was rapid worn out of graphite from the composites having aluminium content more than 50 wt% due to the higher content of graphite (10 and 20 wt%, respectively). In addition, due to the increase of porosity in the different hybrid composites, there was an increase in coefficient of friction observed in some materials. The aluminium nanohybrid composite having 40 wt% titania and 10 wt% graphite showed best results compared with others. Therefore, the optimized hybrid composites with proper sintering condition would significantly help to get suitable structural, mechanical as well as tribological properties for many advanced applications.

Studies on Wear Behaviour of Coated RHA-TIO2-LM24 Aluminium Alloy Composite

Liquid metallurgy method based aluminium matrix composites (AMCs) are extensively utilized in diverse engineering applications including shipbuilding, structural, non-structural, automotive, and aerospace owing to their superior strength, weightless, low density, excellent corrosion, and wear resistance. In the present research work, liquid state technique is employed to prepare the LM4/RHA/TiO2 composites containing four different mass proportion of RHA and TiO2. The weight proportion of reinforcements ie RHA-1,3&5 and TiO2 2,5&6 respectively.From the dry sliding wear studies, it is evident that the incorporation of RHA and TiO2 particles into the LM24 aluminium matrix alloy increases the wear resistance properties up to 45% as compared with the dry sliding behaviour of pure aluminium LM4 alloy. Dry sliding wear results revealed that the parameters like varying weight percentage, sliding speed, and applied load are the direct impact on the wear behaviour of the hybrid composites. A reduction of up to 34 % wear rate was observed by incorporation of 5% of RHA and 1% & 6 %of TiO2 particles as compared with the remaining percentage of reinforcements. The developed Coated RHA-TIO2 -LM24 aluminum alloy composite exhibits excellent mechanical properties, can be used in long-term applications in which saving weight is an important feature, such applications include and automotive engine parts and aerospace industry. In automotive industry, it can be used for making Brake disc, Turbo-compressors, Pump supporting parts, rear axle, differential housing.