Relationship between hardness and fracture toughness in WC–FeAl composites fabricated by pulse current sintering technique

Effect of η-phase and FeAl composition on the mechanical properties of WC–FeAl composites

“…Control of oxygen content is an important aspect in the powder processing technique for making ceramic-metal composites since mechanical properties of metallic materials are sensitive to oxygen. FeAl has good oxidation resistance as a bulk material but oxygen is easily trapped in the FeAl powder subjected to wet milling [11]. The oxygen content of the milled powder is apparently larger than that of the raw powder, indicating that the amount of oxygen adsorbed on the powder surface increases because of the increase in the specific surface area of the powder subjected to wet milling.…”

Effect of Oxygen Content in WC-FeAl Powders on Microstructure and Mechanical Properties of Sintered Composites Fabricated by Pulse Current Sintering Technique

“…These results are consistent with the trade-off relationship between the hardness and the fracture toughness. 14) The increases of 6% in the hardness and the decrease of 8% in the fracture toughness is accomplished by reducing 6% of the O.C., which is very slight variation. On the other hand, the TRS improves up to 2.0 GPa from the composite of the D-R powder having the lowest O.C.…”

“…The authors have developed tungsten carbide iron aluminide (WC-FeAl) composite as an alternative material which does not contain toxic material such as cobalt. 14) It was found that mechanical properties of the WC-FeAl were improved by developing powder preparation and/or sintering techniques. 510) For example, WC-FeAl composites having homogeneous microstructure were successfully obtained by changing powder mixing process from dry type to wet one.…”

Changes in constituents and FeAl composition with oxygen content in WC–FeAl composites

“…However, WC-FeAl composites obtained from a conventional vacuum sintering technique had lower mechanical properties such as fracture toughness or fracture strength than WC-Co hard materials due to several microstructural reasons [4]. This disadvantage has been partially compensated by using pulse current sintering technique, which prevents WC grain growth and formation of huge FeAl phases [5,6]. However, this technique is sometimes inapplicable to fabricating long products such as drills or end mills.…”