High-temperature plastic flow behaviour in the binder of WC-Co cemented carbides

Abstract

Co-rich solid solution alloys regarded as the composition of binder phasesat elevated temperatures in WCCo cemented carbides were fabricated and the high-temperature deformation behaviour of the alloys was investigated. The logarithmic relationship between flow stress and strain rate is expressed by a single straight line with the slope of t).15 at a constant temperature in all strain rate range examined, unlike in cemented carbides showing the sigmoidal behaviour. The solid solution hardening due to the addition of Cr3Cz and VC is negligible in the Co-gWC-1Cr3C:-0.5VC alloy and the mutual relation in flow stress is different between the cemented carbides and their binder phases in region I. The plastic flow in region I in WC-Co cemented carbides cannot be explained by the flow stress or flow behaviour in the binder phase.

Phylogenetic analyses of nuclear rDNAITSsequences of Koreanalliuml. subgenusRhizirideum(Alliaceae)

“…Chung (1956Chung ( , 1965 illustrated 11 species, and Kitagawa (1979) recorded 13 species, one variety, and one forma in Korean Allium. Lee (1996) summerized Korean Allium as 17 species, three varities, and two formas including cultivars. Yu et al (1981) studied the taxonomy of the Korean Allium, and reported 12 species, two varieties, and one forma.…”