| 摘要 |
A sintered body of titanium-based carbonitride alloy according to the invention comprises carbonitride hard constituents in 5-25% binder phase where the hard constituents contain, in addition to Ti, one or more of the metals Zr, Hf, V, Nb, Ta, Cr, Mo and/or W and the binder phase is based on cobalt and/or nickel. The sintered body has at least one outer surface with a <50 mu m thick surface layer of a titanium-rich cubic carbonitride. Below this layer there is a <100 mu m thick binder phase enrichment zone. The binder phase content can be >1.2 of that in the inner part of the body D. Under the binder phase enrichment zone, there is a <250 mu m thick binder phase depleted zone C. The binder phase content in this zone has a lowest level <0.9 of the binder phase content in the inner part of the body D. Such sintered bodies are manufactured by heat treatment in an atmosphere of N2 and/or NH3 possibly in combination with at least one of CH4, CO and CO2 at 1100 DEG -1350 DEG C. for 1-25 hours at atmospheric pressure or higher.
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