Experimental investigations on red ochre for application in welding consumable development

This paper investigates the thermophysical, physicochemical, and surface properties of mineral waste red ochre, assessing suitability for application in welding consumable development. Red ochre is an anhydrous iron oxide derived from tailings of iron ore haematite. High iron and silica concentration makes it suitable for various engineering applications. Iron in the electrode coatings is known to increase arc stability, bead smoothness, and also it enhances slag detachability along with smoothening bead profile. The red ochre has been characterized for the properties of weight loss, density, specific heat, enthalpy, thermal conductivity, and diffusivity. Structural analysis of red ochre powder has been done using Fourier transformed infrared spectroscopy and X-ray diffraction. BET (Brunauer, Emmett, and Teller) surface area analysis has been done to estimate the surface properties, which include pore radius and specific surface area. The shielded metal arc welding electrodes have been developed by adding red ochre in a fixed proportion, and produced welds have been examined for visual defects, microstructure, and microhardness.