Though very important, hardness is only one factor to be
evaluated when comparing the wear resistance of Fe-based
hardfacing welding alloys. For pure abrasion either synthetic
materials using tungsten carbides or complex alloys providing
both hard phases, and a hard and tough nanostructured
matrix at the same time are performing best and very similar.
Under erosive wear or high impact loads, the tungsten
carbide-containing hardfacing alloy underperforms significantly
compared to this new complex type of Fe-based alloy. State of
the art hypereutectic FeCrCNb alloys provide reasonably good
behaviour under all test conditions but never being the leading
edge.
Hypoeutectic FeCrC alloys give considerable hardness, but
have a correspondingly low wear rate only under erosive wear,where they are an economical alternative to higher alloyed materials.
For high impact applications, martensitic materials behave
best, whereas alloying elements as Nb which solidify primarily
are a possible solution to obtain better performance under 3-body
abrasion.