The effect of carbon, Ti and Nb on the formation of hot band texture in ultra-low carbon steels was studied. The chemical compositions were selected so that two of the four steels were fully stabilized with respect to carbon and the other two were expected to have some carbon in solution under equilibrium conditions. The slab reheating temperature ranged from 1 200 to 1 280°C. The first deformation was applied with a 50 % reduction to simulate the roughing pass at 1 150°C. The samples were then deformed with another 50 % reduction at either 1 050 or 920°C. The crystallographic orientations of the resulting ferrite were presented in the form of so-called skeleton plots along the RD-, TD-and ND-fibers. The main texture found was the cube-on-corner, {111}͗110͘, component. The rotated cube component, {001}͗110͘, was also present but its intensity was always lower than the intensity of the cube-on-corner component. The presence of the cube-on-corner texture was explained by the large grain size in the starting as-cast ingots and by the heavy reductions per pass. The combination of low reheating temperature and low finishing temperature generated the highest ratio of {111}/{100}. Decreasing the carbon content from 35 to 17 ppm and adding 90 ppm Nb to a Ti-alloyed ULC steel further increased the {111}/{100} ratio.

Certain micro-devices require sliding contact between components; micro-engines, micro-motors, micro-gears, and near-contact or contact recording hard disk drives are some examples. In these devices tribological problems--namely friction, wear and stiction-determine device efficiency and lifetime. Newly developed carbon films show ultra low friction (lower than 0.05), low wear coefficient (lower than 10 -8 ), and high contact angle of water (higher than 85 degrees). This film has very low adherent property that results in ultra low friction and high contact angle. The hardness and elastic modulus are lower than H-DLC but the ratio of hardness to modulus is similar to values for H-DLC that results in low wear rate. Even though these carbon film has low hardness (2 to 10 GPa), it can be used as a protective layer in micro-devices because the X applied load is very light and contact area is large in micro-device applications. A new oscillating compliant beam method was used to measure friction and wear.

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