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The purpose of this paper is to present results of an evaluation of dual‐phase and galvanized steel reinforcements in corrosive environments.

Low carbon steels were intercritically annealed at 740°C followed by water quenching to obtain dual‐phase structures with 37 per cent volume fraction of martensite dispersed in ferrite matrix. Dual‐phase and galvanized steel rebars were embedded in concrete cubes and immersed in 5 per cent NaCl solution for up to 100 days. Corrosion rate, tensile and macro as well as microhardness tests were performed. The dual‐phase and galvanized zinc layers were observed under scanning electron microscopy (SEM).

From all of the tests carried out it was found that dual‐phase steels exhibited better corrosion resistant properties and superior strength compared to galvanized steels.

The results reported show that dual‐phase steel can be a good candidate for reinforcement in concrete especially in aggressive and corrosive environments.

The purpose of this paper is to examine the effect of substrate temperature on friction coefficient and surface roughness of titanium nitride (TiN) coatings deposited on high‐speed steel (HSS) using commercially available cathodic arc evaporation physical vapour deposition system.

The goal of this work is to determine the usefulness of TiN coatings in order to improve the friction coefficient and surface roughness of HSS verses substrate temperature, as vastly used in cutting tool industry and many others. A Pin‐on‐Disc test was carried out to study the coefficient of friction verses sliding distance. Surface roughness of deposited coatings was studied via surface roughness tester and atomic force microscope (AFM).

Friction coefficient increased at higher temperature as compared to the coating deposited at lower substrate temperature. Surface roughness measured via both instruments showed similar trend in recorded data and, i.e. increased by increasing substrate temperature. AFM study showed that bearing ratio (per cent) decreased, whereas, fractal dimension increased with an increase in substrate temperature.

It is implied that choosing a substrate temperature above 450°C in the existing coating system could damage some machine parts.

This scenario develops an approach to optimize the coating properties verses substrate temperature for specific application, such as cutting tools for automobiles and aircrafts.

The coating deposited at lower temperature showed better friction coefficient and surface roughness than the coating deposited at higher temperature and vice versa.