On the other hand, Co binder gradient formed by liquid state carburizing is due to migration of W atoms driven by diffusion of carbon atoms, leading to coarser and closer WC grains in the surface and inward diffusion of Co atoms.

• 液相渗碳处理时钴相梯度结构形成主要是碳原子扩散驱动下的W原子迁移,导致表层碳化钨晶粒长大并相互靠近,从而使液态钴向合金内部迁移。