Characterization of aluminides formed on superalloy 690 substrate

摘要

Ni-Cr-Fe based superalloy 690 substrate, pack aluminized at 1273 K, revealed formation of multilayer comprising (NiCr)Al + Cr5Al8, Ni2Al3 + Cr_5Al_8, NiAl and y phases. Knoop hardness number varied from 225 to 1142 along the cross-section. Wear and friction tests on aluminized specimen were performed in dry medium using reciprocating sliding wear and friction machine with tungsten carbide ball at 15 N load with frequencies at 10, 15 and 20 Hz.