The effects of Mn and B on the cavitation erosion resistance of austenitic Fe-base hardfacing alloys

The effects of manganese and boron on the cavitation erosion behavior of austenitic Fe–Cr–C–Si–xMn–yB (x = 0, 10 wt%, y = 0, 0.3 wt%) hardfacing alloys were investigated by using a vibratory cavitation erosion tester. It was found that the cavitation erosion resistance increased with the addition of B. The increase of erosion resistance is thought to be due to the enhancement of a strain-induced α′ martensitic transformation caused by grain size refinement with the addition of B. It was also found that ɛ martensite, which was easily formed by addition of Mn, was more effective than α′ martensite at increasing cavitation erosion resistance. When both Mn and B were introduced, the cavitation erosion resistance improved further than was attributed to the enhancement of the strain-induced ɛ-martensite formation alone.