Busari, Yusuf O.Ahmed, Ismaila IdowuShuaib-Babata, Yusuf Lanre2021-05-072021-05-072017-11-29Busari, Y. O., Ahmed, I. I., & Shuaib-Babata, Y. L. (2017). Effect of Heat Input on the Mechanical and Corrosion Behaviour of Smaw Mild Steel Journal of Production Engineering, 20 (2), 59-64. doi: http://doi.org/10.24867/JPE-2017-02-059http://www.jpe.ftn.uns.ac.rs/papers/2017/no2/11-Busari_JPE_20_No2.pdfhttps://uilspace.unilorin.edu.ng/handle/20.500.12484/5179This study was carried out to assess the effect of heat input on the mechanical properties and corrosion behaviour of mild steel. The intrinsic nature of fusion welding has made it difficult to provide a complete understanding of corrosion behaviour in some systems. Optical metallography was used to determine grain size and HAZ zone, weldment and parent metal. Mechanical properties of the weldment were observed. Corrosion behaviour of mild steel were investigated in air, sea water, alkaline and acidic medium after welding with shielded metal Arc welding SMAW by varying the welding process parameter that leads to power input and monitoring its welding speed with a stop watch. The microstructural characterization of the welded sample carried out through a metallurgical microscope (x100) and the corrosion response rate by weight loss was observed in the different medium, the sample welded with 180A and low voltage displayed the highest Rockwell hardness and the same was observed for impact test. The effect of various heat inputs on the corrosion behaviour of shielded metal arc welded mild steel show thus the as-received sample have the greatest resistance to corrosion in all the medium, at 180 A, high voltage this is closely followed by sample welded with 180 A, low voltage. The sample welded with 90A, low voltage which has the least corrosion resistance in all medium during the exposure period studied. The low heat input welded samples underwent a long period of heating, low heat input could lead to a greater tendency of distortion which may produce a higher weld cracking in the aggressive corrosion medium. The higher the current, the higher the power input and the deeper the penetration. However, the use of too high weld current may cause problems such as excessive spatter, electrode overheating and cracking while too high weld voltage could cause the beads to be wider and flatter. The low arc voltage produces a stiffer arc that improves penetration. If the voltage is too low, a very narrow bead will result.enHeat inputcorrosion resistanceweldmentlow voltagehigh voltageArticle