| 摘要 |
A method of heat treating a green compact having an exposed surface. The method includes the steps of: providing a green compact comprised of a hard carbide and binder; placing a powder of grain refiner on at least one portion of the exposed surface of the green compact; and heat treating the green compact and grain refiner powder so as to diffuse the grain refiner toward the center of the green compact thereby forming a peripheral zone (80) inwardly from the exposed surface in which the grain refiner was placed, and forming an interior zone (84). The peripheral zone having a grain size that is smaller than the grain size of the bulk zone. |
