Erosion is a very complex phenomenon, in which not only the properties of the construction material but also those of the eroding particles are significant, e.g. hardness, temperature, velocity, and angle of impact.
Generally, an adherent, tough, and ductile oxide layer is required for good erosion resistance.  In addition, it should be prone to quick and repeated "spontaneous rehealing".  Laboratory tests and service experience have shown that the MA alloys have a very good erosion resistance, outperforming similar and even higher alloyed grades.