PURPOSE: To manufacture a sintered body excellent in the plasticity, the strength, the workability, etc., by precipitating carbon in the ferrous metal in the sintered body where the carbide or the like of the transition metals in the 4a, 5a and 6a groups, Al2O3 or the like, and fine diamond particles are blended at the prescribed ratio.

CONSTITUTION: A sintered body has the composition consisting of, by volume, 15-75% carbide, nitride, or boride of either of the transition metals of the 4a, 5a and 6a groups in the periodic table, or the mixture thereof or the solid solution thereof, 20-30% ferrous metals, 5-20% one or two or more kinds of Al2O3, Y2O3, MgO and ZrO2, and 10-50% fine diamond particles of 1-40μm in grain size, and the sintered body is manufactured where carbon is precipitated in the ferrous metals constituting this sintered body or on the surface thereof. This constitution provide the sintered body for tools excellent in the hardness, the high temperature oxidation resistance, and the wear resistance.