| 摘要 |
Cemented carbides contg. TiC and/or TaC are sintered above the liquidus temp. and cooled to <=1000≦̸C at >=30≦̸C/min by N or Ar circulated and cooled outside the furnace by a heat exchanger. Oxidn. is avoided. Thus, a mixt. of WC 81.5, TiC 5.5, TaC 3, and Co 10% was compacted to a cutting tool tip, heated at ˜200≦̸C to remove the binder, sintered at 1400≦̸C, and cooled 34≦̸C/min˜1000≦̸C by using N. The transverse rupture strength was 220kg/mm2, and flank wear in a cutting test on SCM3 steel was 0.19mm. Comparable values were 190 and 0.31mm for the tool cooled at 10≦̸C/min.
|
