Patent ID: 6699526
Filing Date: 2004-03-02
Classification: B22F,C22C,C23C,Y10T

Abstract:
A method of making a cutting insert comprising a cemented carbide body having a binder phase, with a binder phase enriched surface zone, and a binder phase depleted cutting edge, and a coating, comprising the steps of:forming a powder mixture containing WC, 2-10 wt. % Co, 4-12 wt. % of cubic carbides of metals from groups 4, 5 or 6 of the periodic table, the binder phase having a CW-ratio of 0.75-0.90; adding N in an amount of between 0.9 and 1.7% of the weight of the elements from groups 4 and 5; mixing said powder with a pressing agent; milling and spray drying the mixture to a powder material; compacting and sintering the powder material at a temperature of 1300-1500Â° C., in a controlled atmosphere of sintering gas at 40-60 mbar followed by cooling; applying post-sintering treatment; and applying a hard, wear resistant coating by CVD- or MT-CVD-technique.