An investigation of abrasive wear and corrosion behavior of surface repair of gray cast iron by SMAW

In this work, improving the abrasion-corrosion behavior of gray cast iron used in centrifugal pumps was studied. These pumps are usually made of gray cast iron (BS:1452Gr220) and are repaired by Shielded Metal Arc Welding (SMAW). Three different typical welding electrodes including Ni electrode (DIN8563), Carbon Steel electrode (DIN1913), and Hardening electrode (DIN8555) were used to compare the weldability of the base metal. Microstructural differences for three types of electrodes were studied and forming of different phases was analyzed. Corrosion and abrasion tests were conducted and related to welding conditions. Experimental results showed that using Ni substrate electrode reduce the unwanted phases (martensitic and carbides). Furthermore, in comparison with the base metal, the abrasion behavior of all weldments was improved. It was also determined that the carbon steel electrode has a higher corrosion resistance in zero-resistance ammeter (ZRA) test compared to other electrodes.