Bonding mechanism of X10CrNi18-8 with Ni/Al₂O₃ composite ceramic by pressureless infiltration

Abstract

An alloy steel/alumina composite was successfully fabricated by pressureless infiltration of X10CrNi18-8 steel melt on 30% (mass fraction) Ni-containing alumina based composite ceramic (Ni/Al₂O₃) at 1 600 °C. The infiltration quality and interfacial bonding behavior were investigated by SEM, EDS, XRD and tensile tests. The results show that there is an obvious interfacial reaction layer between the alloying steel and the Ni/Al₂O₃ composite ceramic. The interfacial reactive products are (Fe_xAl_y)₃O₄ intermetallic phase and (Al_xCr_y)₂O₃ solid solution. The interfacial bonding strength is as high as about 67.5 MPa. The bonding mechanism of X10CrNi18-8 steel with the composite ceramic is that Ni inside the ceramic bodies dissolves into the alloy melt and transforms into liquid channels, consequently inducing the steel melt infiltrating and filling in the pores and the liquid channels. Moreover, the metallurgical bonding and interfacial reactive bonding also play a key role on the stability of the bonding interface.

Keywords

pressureless infiltration / steel/alumina composites / interface bonding / infiltration mechanism