Temperature Distribution in Metallic Powder Particles During Initial Stage of Field-Activated Sintering

The temperature distribution in copper and martensitic steel spheres has been investigated for the initial stage of field‐activated sintering (FAST)/spark plasma sintering (SPS) using capacitor discharges (CD) with applied voltages from one to 15 V as model experiments. At first, the evolution of th...

Full description

Saved in:
Bibliographic Details
Published in:Journal of the American Ceramic Society 2015-11, Vol.98 (11), p.3547-3552
Main Authors: Trapp, Johannes, Kieback, Bernd
Format: Article
Language:English
Subjects:
Coatings
Contact resistance
Copper
Electric currents
Electric potential
Melting
Plasma sintering
Sintering (powder metallurgy)
Spark plasma sintering
Temperature distribution
Voltage
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The temperature distribution in copper and martensitic steel spheres has been investigated for the initial stage of field‐activated sintering (FAST)/spark plasma sintering (SPS) using capacitor discharges (CD) with applied voltages from one to 15 V as model experiments. At first, the evolution of the contact resistance between the spheres has been studied. The results show the reduction in the contact resistance after discharge with increasing electrical load, yet no significant dependence on the length or number of the discharge pulses. Thereby the initial resistance is only decreased distinctly if at least a certain minimal voltage was applied. Subsequently, the melting of thin coatings of different metals on copper spheres has been studied and the occurrence of molten phase and its melting point were assigned to the corresponding discharge current. Extrapolation from the currents necessary to melt the coating layers in the CD experiments to lower values typical for FAST was used to estimate the contact overtemperature in the latter case. Resulting values for copper range from 0.05 K for normal heating with 100 K/min to 5 K for maximum current output.
ISSN:0002-7820
1551-2916
DOI:10.1111/jace.13757