| 摘要 |
<p>A cubic boron nitride (cBN) sintered compact for an end mill is disclosed which is obtained by sintering a mixed powder prepared by mixing about 35 to 50 percent by volume of cubic boron nitride powder having an average particle size smaller than about 2 .mu.m with about 50 to 65 percent by volume of a binder under cBN-stable superhigh pressure conditions. The binder contains about 20 to 30 percent by weight of Al and one or more Ti compounds selected from the group TiNz, Ti(C,N)z, TiCz, (Ti,M)Cz, (Ti,M)(C,N)z and (Ti,M)N (where M indicates a transition metal element of group IVa, Va or VIa of the periodic table other than Ti and z is within the range of about 0.7 < z < about 0.85). The atomic ratio of Ti contained in the binder to the total of the transition metal element M and Ti is from about 2/3 to 97/100. The total tungsten concentration of tungsten contained in the binder in the form of at least one tungsten carbide or the Ti compound described above is about 5 to 20 percent by weight.</p> |
