Enhanced sintering of an Fe-Ni-P coated composite powder prepared by electroless nickel plating

Abstract

An Fe-8.2 % Ni-6.0 % P powder was prepared by electroless nickel plating on a carbonyl iron powder, where phosphorous appeared as a contaminant of the plating process. Because of the high phosphorous concentration, persistent liquid phase sintering was effective at temperatures higher than 1000 ~ The sintered microstructure was dramatically different from the conventional approaches, where a low concentration of phosphorous was added in the form of Fe3P. Sintering the alloy at a temperature as low as 1050 ~ for 30 min yielded a sintered density of 98.6% theoretical and rounded grains having an average grain size of 53 ttm. The rounded grains were surrounded by a large volume fraction of intergranular (Fe,Ni)3P phase, arising from the high phosphorous concentration, which slightly deteriorated the magnetic saturation but significantly increased the electrical resistivity of the alloy. Generally speaking, the magnetic saturation of the sintered alloy was improved with respect to the iron-phosphorus, iron-nickel, or iron-silicon alloys fabricated by powder processing.

Low-Temperature Induced Martensitic Transformation Enhancing Mechanical Properties of Metastable Fe-Ni-P Alloy

“…Therefore, there is an increase in strain hardening rates of alloy S-RT and alloy S-CT1. In fact, the precipitation of phosphide is a dynamic process that is dependent on sintering time and temperature, and the conventional sintering process can provide favorable conditions for its formation [19,20]. However, in this Fe-Ni-P alloy prepared by SPS process, a higher heating rate and a lower sintering temperature make the semi-liquid Ni-P phase to exist temporarily during the sintering process.…”

Characterisation of electroless nickel plated titanium powder

“…Deposition of nickel on the iron powder has been applied with goal of fabricating intricate parts possessing good soft magnetic properties and enhancement oxidation behaviour. [15][16][17][18][19] Also, this method has been used for a creation nickel layer on aluminium, 20,21 titanium, 22,23 tungsten [24][25][26] and some ceramic powders. [27][28][29][30][31][32][33] The nickel coated metallic/ceramic powders can be used to produce components with an improved microstructure as well as enhanced properties via the powder metallurgy process.…”