Search

In this research, low carbon steel and Al-1200 series was used in the development of galvanneal steel; hot dip technique was adopted for the immersion at varied time ranging between 0 and 60 seconds. Muffle furnace was used for the annealing operation which precedes the corrosion experiment where weight loss technique was adopted. From the result, it was observed that the sample hot-dipped and held for 30 seconds gives better adhesive property between Al-Zn and Fe substrate thus indicating that it is feasible to develop galvanneal steel using low carbon steel. Aluminium (1200 series) and zinc was generally found to improve the corrosion resistance of the steel, thus galvanneal steel has better corrosion resistance in simulated sea water to represent the saline environment. [ABSTRACT FROM AUTHOR]

In this research work, the fracture mode of dual phase medium carbon low alloy steels which was subjected to uniaxial tensile testing, was studied. The dual phase microstructure was developed by adopting intercritical heat treatments at an isothermal temperature of 770°C for holding times of 15, 30 and 60 min. After characterising the tensile properties with the aid of a universal tensile testing machine, a scanning electron microscope (SEM-EDS) was further employed to analyse the microstructure of the developed DPS. From the results, it was observed that despite high strength being induced in the steel, the strain-to-fracture remains near 25%. The presence of dimple fractures and pull-outs, which led to the realisation of the existence of intermetallic compounds, was also obtained from the fractographs. In general, sample B-2 was soaked for 30 min and exhibits the best combination of mechanical properties. [ABSTRACT FROM AUTHOR]