Abstract
The overlay of boride cermet was fabricated on low carbon steel by plasma transfered arc welding with the composite powders made from MoB, Ni and so on. Dispersed boride ceramics were hardly found in the overlay alloy, when using agglomerated powder was used. On the other hand, the micro-structure consisted of dispersed Mo2NiB2 particles and Ni matrics were formed successfully, when semi-sintered powder was used.
Weight loss for abrasion and corrosion resistance for molten aluminum of the Mo2NiB2-Ni cermet overlay were examined. Its weight loss in abrasion test was one fifth of Cc alloy (Stelite #12), and its corrosion resistance was superior to the nitrided alloy steel extremely. However, this boride cermet is not so suitable to overlay alloy, because it is too difficult to control its microstructure of overlay.
