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Chitosan is a naturally available biopolymer. It has been prepared by alkaline N-deacetylation process of shrimp (Crangon crangon) chitin and fish (Labeorohita) chitin. The physico-chemical properties such as the degree of deacetylation (DD), solubility, water binding capacity, fat binding capacity and chitosan yield have indicated that shrimp shell and fish scale waste are good sources of chitosan. The deacetylation value of shrimp shell chitosan, fish scales and commercial chitosan was found to be 76, 80 and 84%, respectively. The crystalline index (CrI) of fish and shrimp shell was 84 and 82%. Fat binding capacity of fish chitosan, shrimp chitosan and commercial chitosan was found to be 226, 246 and 446%, respectively. Fourier transforms infrared spectroscopy (FTIR) spectra presented a detailed structure of α-chitin with O-H, N-H and CO stretching movements. Structural differences between shrimp chitosan and fish chitosan were studied by using FTIR, thermo-gravimetric analysis (TGA), Xray powder diffraction (XRD) and scanning electron microscopy (SEM). FTIR spectra were used to determine the chitosan degree of deacetylation (DD). Characteristic properties of extracted chitosan were found to depend upon the source of origin and degree of deacetylation.

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TiC-Cu tool electrode prepared by the powder metallurgy route has been used to deposit TiC coating on AISI 1020 mild steel by the electro-discharge coating (EDC) process. Different ratios of TiC and Cu were considered to make a tool electrode that enables to produce acceptable quality coating. The effect of peak current and pulse duration during the EDC process was analyzed for the deposition rate and surface characteristics of the coating. The microhardness of the coated surface was measured by Vickers microindentation tester and microstructure of the deposited layers was studied by scanning electron microscopy (SEM). The elements present in the coating were analyzed through energy-dispersive spectroscopy (EDS), and the compounds formed during the coating process were identified by the XRD technique. The wear rate of the coated samples was measured through ball-ondisc-type sliding wear test against WC-Co ball. Analysis of the experimental results revealed that a higher peak current during the EDC process augmented the microhardness and wear resistance of the coating.