Electrically conductive composite material PANI- Zr(IV) molybdophosphate (PZMP) was synthesized, via treatment of Zr(IV) molybdophosphate with PANI(polyaniline) gel. The membrane of this material is fabricated for detection of mercury in waste samples. By using 4-in-line-probe the conducting behaviour of the material was determined, and it was found that conductivity of the nanocomposite lies in the range of semiconductors. The composite showed In this study, base composition without alloying elements and three microalloyed steels containing 0.08% wt V, 0.06% wt Nb and 0.06% wt Nb-0.1% wt V in induction furnace, in controlled condition, were casted. Temperaging were carried out on all of specimens for precipitation strengthening. For studying the influence of temperaging time and temperature, specimens with different chemical compositions were temperaged at 400,500,600 and 700 ℃ for 1,3 and 5 h. All of specimens in as-cast condition were studied using optical microscope and hardness tester. Results showed that as-cast specimens having ferrito-pearlitic microstructures. Nb-bearing specimens shows acicular microstructures. The heat treated samples were studied using Electron Microscope Analysis and hardness tester. Studying of mechanical properties of heat treated specimens, showed that because of precipitation strengthening, hardness of samples increased. By increasing of temperaging temperature in a constant time, hardness has an optimum value.