Microstructure and Wear Resistance of Novel TBM Cutter Ring Steel

TBM cutter ring is an alloy steel required a high level of strength, toughness and abrasion resistance. The comprehensive performances of H13 and DC53 cutter ring steels need improving. In this paper, a novel TBM cutter ring steel DB1 with better strength and toughness was developed by optimizing the concentration of alloying element. The microstructure and fracture morphology of DB1, H13 and DC53 steel were studied via scanning electron microscope. The wear properties of DB1, H13 and DC53 under different loads and different hardness of rock were studied via wear testing machine, and the wear surface morphology was studied by scanning electron microscope. The results showed that the size and content of primary carbides had important effects on the hardness and toughness of TBM cutter ring material. Proper amount of primary carbide was helpful to improve the hardness and wear resistance of cutter ring material. Excess primary carbide led to a sharp decrease in the toughness. There was a matching behavior between TBM cutter ring and rocks with different compressive strengths. DB1 steel had better wear resistance in cutting rock with moderate compressive strength.