Gradient Characteristic of Functionally Graded Cemented Carbide
The invention of functionally graded structure cemented carbide is a significant revolution. In this paper, graded structure cemented carbide with cubic carbide free layer (CCFL) was prepared. Using scanning electron microscope (SEM), metallographical microscope, electroprobe microanalyzer and microindentation, the gradient characteristics were investigated. The variation in elemental compositions from surface to inner is gradient, the concentrations of nitrogen and titanium are very low in surface layer, only element of tungsten, cobalt and carbon exist. A cobalt concentration peak occurs, which is higher than the average composition in bulk. Wherein binder phase piles up, its volume fraction is much higher than nominal value, resulting in a decrease in hardness and forming a tough layer.
Zhengyi Jiang and Chunliang Zhang
P. Feng et al., "Gradient Characteristic of Functionally Graded Cemented Carbide", Advanced Materials Research, Vols. 97-101, pp. 1332-1335, 2010