TY - JOUR

T1 - Elimination of oxide films during Spark Plasma Sintering of metallic powders

T2 - A case study using partially oxidized nickel

AU - Dudina, Dina V.

AU - Bokhonov, Boris B.

PY - 2017/2/1

Y1 - 2017/2/1

N2 - We present a case study addressing the issue of surface cleaning of the particles of metallic powders from oxide films during Spark Plasma Sintering (SPS). Based on the results obtained using an intentionally oxidized powder of carbonyl nickel (O/Ni(at.) = 0.2), we show that when the powder is heated in the SPS chamber but is not in direct contact with graphite foil commonly used in the SPS practice, the reduction of the oxide is limited to the surface layers of the powder bed. Comparative sintering experiments with graphite and copper foils indicate that a direct contact with a source of carbon is critical for the elimination of the oxide from the sintered compact. Compacts/regions of the compacts, in which nickel oxide NiO was reduced, showed more pronounced inter-particle necking than the regions maintaining the initial oxide concentration.

AB - We present a case study addressing the issue of surface cleaning of the particles of metallic powders from oxide films during Spark Plasma Sintering (SPS). Based on the results obtained using an intentionally oxidized powder of carbonyl nickel (O/Ni(at.) = 0.2), we show that when the powder is heated in the SPS chamber but is not in direct contact with graphite foil commonly used in the SPS practice, the reduction of the oxide is limited to the surface layers of the powder bed. Comparative sintering experiments with graphite and copper foils indicate that a direct contact with a source of carbon is critical for the elimination of the oxide from the sintered compact. Compacts/regions of the compacts, in which nickel oxide NiO was reduced, showed more pronounced inter-particle necking than the regions maintaining the initial oxide concentration.

KW - Carbon

KW - Nickel oxide

KW - Reduction

KW - Sintering

KW - CU

KW - CARBON

KW - SPS

KW - MECHANICAL-PROPERTIES

KW - MICROSTRUCTURE

KW - CERAMICS

UR - http://www.scopus.com/inward/record.url?scp=85010807518&partnerID=8YFLogxK

U2 - 10.1016/j.apt.2016.12.001

DO - 10.1016/j.apt.2016.12.001

M3 - Article

AN - SCOPUS:85010807518

VL - 28

SP - 641

EP - 647

JO - Advanced Powder Technology

JF - Advanced Powder Technology

SN - 0921-8831

IS - 2

ER -