Preparation of FeB-Ni Hard Materials by Both Electroless Plating and Spark Sintering, and Their Mechanical Properties

Abstract

FeB-Ni hard materials were consolidated by both electroless plating and spark sintering processes for the development of ubiquitous hard materials. Uniform nickel layers were formed quantitatively on as-received FeB powder surfaces. The amorphous Ni layers transformed to poly-crystalline during spark sintering. Sintering curves of FeB-Ni compacts showed the similar behaviors regardless of Ni contents, although their apparent relative densities were increased with the increment of Ni contents. Moreover, the sintering mechanism of FeB-Ni and pure Ni compacts consisting of both the plastic deformation and power law creep deformation occurred during spark sintering. Their maximum points of Ḋ were shown in the D of approximately 0.78. The plastic and power law creep deformation were predominantly consolidation mechanisms before and after maximum Ḋ, respectively. Values in H R A of FeB-Ni compacts were decreased with increment of the Ni contents. The compressive stress of FeB-Ni compacts was decreased with the increment of the Ni contents in contrast to the compressive strain.

Consolidation Behaviors of FeB–25Ni Powders in Spark Sintering and Mechanical Properties of Their Compacts

“…FeB-10Fe showed improved sintering behavior as compared to FeB-0Ni, which corresponded to the promotion of densi cation by the deformation of Fe binders 29) as well as Ni binders. The FeB-10Ni 30) compact showed an apparent relative density of 0.8 at 1190 K, in the region of high temperatures above 1000 K. In contrast, the FeB-10Fe compact showed an apparent relative density of 0.8 at 1260 K. The addition of Ni therefore resulted in the improvement of sinter-ability achieving the same density level at a temperature 70 K lower. The results also show the homogeneous distribution of Ni by electroless plating.…”