Sinterização Isostática

Pressure sinter and HIP on c e m e n t e d c a r b i d e s
The single largest u s e in e c o n o m i c t e r m s of c e m e n t e d carb i d e s is t h a t o f i n d e x a b l e inserts used for machining.
Major applications also exist in the field of m a k i n g components u s e d in m e t a l forming, as well as solid carbide tooling used for drills, end mills, and a broad v a r i e t y of w e a r a n d s p e c i a l applications. Bernard North,
W.R. Pfouts and M.S. Greenfield of K e n n a m e t a l Inc, Latrobe, Pennsylvania,
USA,
consider the interaction of processing and compositional and microstructural variables of ce~ E - - L . . .

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mented carbide with any changes in physical and m e c h anical properties which result f r o m t h e s e t r e a t m e n t s . The relevance of post-densification treatments, in particular grinding and~or coating, is discussed in terms of h o w surface condition m a y override or support internal microstructural changes due to pressure sinter or HIP. The authors also d r a w some general conclusions linking the use of pressure sinter or
HiP to carbide grade, process route, s u r f a c e condition a n d product application.
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FIGURE 1: Cemented carbide schematic compositional diagram.

FIGURE 2: Cemented carbide production route. "",
!; Liquid I

WC

&,r.,ght"

TiC, TaC,
NbC, Other

Carbide/Nitride

Metal

bWC
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owder i /f Other /
\Powders

Wet

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Mill

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Dry
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gas
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40 MPR December 1991

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0026-0657/91/$3.50 © , Elsevier Science Publishers Ltd

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emented carbides are composites of transition metal (primarily tungsten) carbides with a binder metal
(usually cobalt). Processing is by a