Effect of V and Si on the Microstructure of Deposits Welded Using Tubular Coated Electrodes with High Mn Content (Hadfield)

Abstract:

Fe-Mn-C (Hadfield) alloys for surfacing weld deposits have demonstrated excellent wear resistance under high dynamic loads. In recent years, numerous studies have been conducted to improve their wear resistance and performance through the introduction of others alloying elements. In the present work, microstructure and hardness of high Mn surfacing welds with 1.2% V and 2.4% Si additions were investigated. The surfacing welds were deposited using experimental tubular coated electrodes. Phases and micro constituents in the resulting deposits were identified using optical microscopy (OM), scanning electron microscopy (SEM), X-ray diffraction (XRD), hardness and micro hardness. Based on the obtained results, V additions to the alloy led to the formation of austenite as predominant phase. Besides, contributed to the formation of vanadium carbides (VC), without the presence of complex carbides. Otherwise, Si addition favored the formation of an interdendritical ferrite network. The addition of these elements favored the increase in the properties of the weld deposits, potentializing their use in applications that require high wear resistance under high loads.

>Key-words: Hadfield; Microestructure; Surfacing; Vanadium; Silicon