Synthesis And Characterization Of Bulk Metal Matrix Nanocomposites Prepared By Pulsed Co-Electrodeposition And Mechanical.: -Thermal Synthesis..Nanostructured Nickel Matrix Composites Reinforced With Nanosized, Undoped, Tetragonal Zirconia Has Been Synthesized By Cathodic Pulsed Electrodeposition. The Reinforcement Is Synthesized By The Aqueous Combustion Synthesis Route With Glycine As The Fuel And Zirconyl Nitrate As The Oxidizer. The Powders Are Prepared By Using Different Glycine To Zirconium Nitrate Molar Ratios (G/N). The Powders With The Best Properties Are Used For Co-Deposition. The Ni-Zro2 Nanocomposites Are Produced From Ni Watt’s Bath With Varying Concentrations Of Zro2 Dispersed In The Solution. The Reinforcement And Composite Have Been Characterized By The Xrd, Tem And Sem Coupled With The Eds. The Microhardness And Thermal Stability Of The Composite Are Evaluated. These Values Are Compared With Those Of Pure Nickel Deposited Under The Same Condition. The Results Show That The Microhardness Of The Nickel Matrix Is Enhanced By The Presence Of The Reinforcement From 450 To 675 Vhn. Thermal Stability Of Ni-Zro2 Nanocomposite Is Investigated By Differential Scanning Calorimetry (Dsc). Grain Growth Kinetics For Nanostructured Nickel Matrix Is Studied By Means Of Isochronal Annealing. The Activation Energy For The Grain Growth Of The Ni Matrix Is Found To Be 118-147 Kj/Mol From The Modified Kissinger Analysis, Which Is Comparable To The Activation Energy For The Grain Boundary Diffusion In Nickel. The Corresponding Change In Microstructure Has Been Monitored In The Temperature Range Between 50 And 600 Oc Using Techniques Of High Temperature Xrd And Electron Microscopy. Results Show That Zro2 Co-Deposited With Nickel Lead To The Reduction In The Nanocrystalline Nickel Grain Size. These Defects Reduce The Recrystallization Temperature Of Nickel Matrix. However, The Co-Deposited Zro2 Effectively Inhibits The Growth Of The Recrystallized Nickel Grains. Aluminum Based Metal Matrix Composites Reinforced With In-Situ Aluminides And Al2o3 Hybrid Reinforcements Are Prepared By The Mechanical-Thermal Synthesis (Mts). The Composites Are Fabricated From The Powder Blends Consisting Of Thermite (Al + Mo) Mixture In Aluminum Matrix. The Onset Temperature For The Thermite/In-Situ Reaction Is Brought Down Below The Melting Temperature By Nano-Structuring Of The Thermite Mixture With Excess Aluminum By The High Energy Ball Milling (Hebm