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The Surface roughness and image texture features of milled surfaces are key parameters to study the surface characteristics of end milled AA 6061 alloy. A Machine vision system is employed to capture and store the images of the end milled workpieces.The stylus type instrument is used measure the surface roughness values of various milled workpieces for different cutting conditions such as speed, feed and depth of cut.The Grey Level Cooccurance Matrix [GLCM] is introduced to extract the image texture features of the end milled surfaces. Four Matrices about different sampling orientations are builtup to determine the various image texure features such as contrast, homogenity, correlation and energy. A regression analysis is performed between image texture features and surface roughness values of the machined surfaces. Finally, the relationship between surface roughness and image texture features has been established.

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The effect of polyurethane on the mechanical properties and Mode I and Mode II interlaminar fracture toughness of glass/epoxy composites were studied. Polyurethanes (PU) synthesized using polyols and toluene diisocyanate were employed as modifier for epoxy resin by forming interpenetrating polymer network. The PU/Epoxy IPN was used as matrix material for GFRP. PU modified epoxy composite laminates having varying PU contents were prepared. The effect of PU content on the mechanical properties like interlaminar fracture toughness (Mode I, G 1c and Mode II, G IIc ), tensile strength, flexural strength, and Izod impact strength were studied. The morphological studies were conducted on the fractured surface of the composite specimen by scanning electron microscopy (SEM). Tensile strength, flexural strength, and impact strength of PU-modified epoxy composite laminates were found to increase inline with interlaminar fracture toughness (G 1c and G IIc ) with increasing PU content to a certain limit and then it was found to decrease with increase in PU content. It was observed that toughening of epoxy with PU increases the Mode I and Mode II delamination toughness up to 17 and 120% higher than that of untoughened composite specimen, respectively. POLYM. COMPOS.

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