The present investigation mainly concentrates on work done in order to explore physical, mechanical & tribological characteristics of Al6061 alloy reinforced with nano-sized zirconium dioxide particulates. Four casts of different percentages of reinforcement from 0 to 6 wt% in the steps of 2 are fabricated using liquid metallurgy technique (stir casting). The prepared composites later subjected to various physical, mechanical & wear tests and results were studied. The tests were carried out in accordance with the ASTM standards on the alloy and nano-composites. In the present investigation the physical and mechanical properties like density, hardness and tensile strength increased significantly with the increase in percentage of reinforcement in the matrix alloy, while the percentage elongation found to be decreased. The sliding wear tests were performed by using pin-on-disc the tribometer and results indicated that wear resistance of composites was higher. Off the four compositions, there were improved properties of composites with higher weight percent of reinforcement. Scanning Electron Microscope (SEM) micrographs was used after tensile testing to study fractured surfaces of specimens and wear morphology after wear testing. Overall the investigational outcomes are very interesting and motivates to do further more research.

The alkyl monoesters of fatty acids derived from vegetable oils or animal fats, known as bio diesel, are attracting considerable interest as an alternative fuel for diesel engines. Biodiesel-fueled engines produce less carbon monoxide, unburnt hydrocarbons, and particulate emissions than diesel-fueled engines. However, bio diesel has different chemical and physical properties than diesel fuel, including a larger bulk modulus and a higher cetane number. Some of these properties can be affected by oxidation of the fuel during storage. These changes can affect the timing of the combustion process and potentially increase the emissions of oxides of nitrogen. The objective of this study was to evaluate the effect of injection and combustion timing on bio diesel combustion and exhaust emissions. Bio diesel fuel is a clean burning fuel made from natural renewable sources such as rice bran vegetable oil. Bio diesel operates in compression ignition engines similar to diesel fuel. It can be burnt in any standard unmodified diesel engine blended with 20% to 30% bio diesel with diesel. Rice bran oil can be converted into bio diesel fuel as ethyl ester by transestirification. Experimental investigations have been carried out using bio diesel as an alternative fuel in single cylinder, compression ignition engine under varying operating conditions and by varying the injection timings with respect to TDC. In this work various parameters such as brake power, peak pressure rise, and emissions during combustion process under varying operating conditions with diesel, bio diesel, bio diesel blends were measured. The exhaust emissions from the engine were measured using exhaust gas analyzer.