Al-WC nano-composite powder produced by mechanical milling

In this study, a conventional nano-grained tungsten carbide (WC) powder was mixed with 50 %wt. of a submicron aluminum (Al) powder in a ball mill for varying milling time periods, producing a homogeneous powder mixture which can be used to prepare FGM using centrifuge casting processes. Parameters of the dry milling process were adapted in order to maximize the mixing effect on the one hand, and to avoid particle growth during the milling process on the other. X-ray diffraction (XRD) investigation indicated a decrease of the crystallite size of WC in combination with an increase in defect density, as well as a strong increase in stacking faults in the Al. The main action of the milling mechanism is the fracturing of the WC particles. Al is distributed consistently around the WC particles. The preparation method used is a useful technique to prepare homogeneous powder mixtures of WC–Al with particle sizes below 30 nm on a laboratory scale.

Keywords:

Mechanical Milling , Nano-Composite , Al-WC