Comparative study of hardfacing applications on structural steel surfaces to improve ballistic properties

The aim of this study was to develop plates resistant to ballistic limits by welding on S355JR steel plate with Fe-Cr-C and austenitic electrodes. A total of four different weld coated materials were prepared for ballistic testing. For these four different coatings, E Z Fe 14 (Fe 14), E Fe 16 (Fe16) hardfacing electrodes and E 18 8 Mn R 3 2 (307) austenitic stainless steel electrode were selected, respectively. The coatings were made in the electric arc welding machine, with two different coatings on the surface for each material. These are Fe 14 - Fe 14, Fe 16 - Fe 16, 307-Fe 14 and 307-Fe 16, as the first layer and the second layer, respectively. In all coatings, the welding current was kept constant at 150 A and the welding voltage was kept constant at 27 V. The microstructure, hardness, and ballistic properties of the hardfacing surfaces were investigated using scanning electron micro-scopy (SEM) and X-ray diffraction analysis (XRD) to analyze the phases and components. The hardnesses of the hardfacing surfaces were determined by Vickers methods from the weld metal to the base metal. Ballistic tests were conducted according to NIJ Level III standards, firing 7.62 x 51 mm AP bullets from a distance of 10 m to calculate the effects of the bullets on the plates, the kinetic energy of the bullet, and the amount of energy absorbed by the plates. Welding for hard surface coating achieved with the combination of 307 -Fe 14 electrodes provides the highest ballistic limit velocity at 830 m/s, while the lowest limit is observed in the material welded with Fe16-Fe16 electrodes at 747 m/s. Fe-Cr-C electrodes were found to be effective as main or auxiliary components when designing armor plates. This study highlights the potential of hardfacing techniques to improve the ballistic properties of steel surfaces, with implications for the development of protective materials across various industries.