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Nanocomposites of PMMA+MMT Brazilian clays were developed by mechanical mixing in co-rotational twinscrew extrusion and injection molding with varying weight fraction of MMT Brazilian clays. The clays were purchased in crude form and then washed and purified to extract the organic materials and contaminants. Dynamic friction and wear rate of these composites were studied as a function of concentration of the Brazilian clay. With an increase in the amount of MMT Brazilian clay, the dynamic friction of the nanocomposites increases, a clear but not large effect. It can be explained by sticky nature of clay; clay in the composite is also on the surface and sticks to the partner surface. The wear rate as a function of the clay concentration passes through a minimum at 1 wt% MMT; at this concentration the clay provides a reinforcement against abrasion. At higher clay concentrations we see a dramatic increase in wear – a consequence of clay agglomeration and increased brittleness. The conclusions are confirmed by microscopy results

D2 belongs to traditional steels, frequently used in metalworking industry. Shot peening and nitriding are known to improve the wear resistance of D2. In this work we focus on processes of slide burnishing and industrial low temperature gas nitriding. The D2 steel specimens were first subjected to heat treatments (HT) prescribed by the manufacturer, turning (T), then burnishing (B) and nitriding (N). The reason for turning was achieving appropriate surface roughness. Deformation induced in slide burnishing can be better controlled then in shot peening because of deterministic nature of this process.

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