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Weld cladding is a process of depositing a thick layer of anticorrosive metal on a corrosive substrate surface to impart better corrosion resistance properties. In weld cladding process, the difficulty generally encountered will be the problem of selecting optimum combination of input process parameters to achieve the desired dilution level. Until recently trial and error methods were employed to determine the optimum process parameters, which result in wastage of cost and time. This paper focuses on optimization of GMAW process parameters, which are used for deposition of austenitic stainless steel on low carbon structural steel plates. Experiments were conducted based on four-factor five-level central composite rotatable design with full replication technique. Mathematical models relating to gas metal arc welding process parameters to clad bead geometry were developed using multiple regression method. Developed mathematical models are helpful in predicting the clad bead geometry and in setting process parameters at optimum values to accomplish the desirable dilution level at relatively low cost with a high degree of reproducibility. The accuracy of the results was tested by conducting conformity tests using the same experimental set up. Moreover, Genetic Algorithm tool with GUI available in MATLAB 7.0 was used to optimize the process parameters to achieve optimum dilution.

Carbon nanotubes (CNTs) reinforced aluminum matrix composites were fabricated using powder metallurgy technique. The effect of nanotubes content on mechanical properties of the composites was investigated. Experimental results showed that nanotubes are homogeneously distributed in the composites. The corrosion of AA 4032 alloy based nanocomposite with CNTs was investigated by electrochemical polarization studies. CNTs-reinforced composites have shown a better corrosion resistance than parent alloy. The nanotubes content significantly affect mechanical and corrosion properties of composite.

In this work, multi-walled carbon nanotubes (MWNTs) were successfully reinforced in AA 4032 nanocrystalline matrix. The elemental powders of AA 4032 composites were mechanically alloyed in the high energy ball mill for 30 h to get nanocrystalline structure. The carbon nanotubes (CNTs) were added at the 29th hour of ball milling process. The morphological changes during milling were studied, using scanning electron microscope analysis and the distribution of the CNTs within the aluminum matrix was successfully revealed, using transmission electron microscope analysis. The results show that the CNTs are effectively distributed within the aluminum matrix without any structural damage. The variation in the melting point was studied using simultaneous thermal analyzer.