The present document describes a composite material adapted to resist degradation by an erosive agent. The composite material comprises a steel base and crystals embedded in the steel base. At least 50% of the crystals have an elongated portion. Optionally, the composite material comprises an external surface for exposure to the erosive agent. At least 50% of the elongated portions are transverse to the external surface. A filler material is also described for forming the composite material on a ferrous surface by welding. The filler material comprises iron, carbon, boron, molybdenum and silicon. Methods are also described form forming the composite material.