HIGH-CHROMIUM NICKEL ALLOY WITH EXCELLENT RESISTANCES TO WEAR AND LEAD CORROSION AND ENGINE VALVE

摘要

A high-Cr nickel alloy having excellent resistances to wear and lead corrosion and containing 0.01-0.5 wt.% C, 0.01-1.0 wt.% Si, 0.01-10.0 wt.% Mn, 35.0-60.0 wt.% Cr, 5.0-25.0 wt.% Fe, 8.0-15.0 wt.% Nb, and the balance consisting of Ni, and inevitable impurities. As the addition of Nb causes fine rigid particles of Nb-Ni and/or Nb-Fe intermetallic compounds to be dispersed and deposited reticularly in a matrix, a sufficient wear resistance can be attained and the attack to the mating materials can be inhibited. When toughness is of primary concern, it is preferably to add 0.01 to 1.0 wt.% Mn, because the toughness is particularly high and defectives due to cracking in surfacing are reduced in this range. When, however, lead corrosion resistance is of primary concern, it is preferable to add over 1.0 to 10.0 wt.% Mn, because the lead corrosion resistance in a reducing atmosphere such as an actual engine combustion gas is particularly high in this range.