|
|
Effects of Si content on properties of Al-Si alloy powders produced by supersonic gas atomization |
FU Jun-hua1, ZHANG Shao-ming1, XU Jun1,2, ZHAO Xin-ming1,2 , SHENG Yan-wei1,2 |
1. National Engineering and Technological Research Center for Non-Ferrous Metals Composites, General Research Institute for Non-ferrous Metals, Beijing 100088, China 2. Beijing COMPO Advanced Technology Co., Ltd., Beijing 101400, China |
|
|
Abstract Fine droplets of Al-11Si, Al-22Si, Al-27Si and Al-50Si (mass percent) were produced using supersonic high-pressure gas atomization. The particle size of powders was carried out by using an ASTM standard sieve with a vibratory shaker. Scanning electron microscopy (SEM), optical microscopy (OM) and X-ray diffraction (XRD) were used to the hierarchy of different microstructure. The [D50] (particle size on average) of Al-Si alloy powder is 57 μm, and the geometric standard deviation [δ] is less than or equal to 1.38, which is much lower than conventional gas atomization powder. The morphology of Al-Si powder is spherical or ellipsoidal sphere. There are fine particles adhered to the larger particles. The smooth finish of particles becomes worse with increase of Si content. Dendrite Al, eutectic and primary Si have been observed in the powders. The primary Si content increases and changes from particle to slice with the increase of Si content. The powder particle size has an effect on phase content, and the eutectic phase content increases with the decrease of particle size when the Si content is more than 11wt%.
|
Received: 24 February 2014
Published: 16 October 2014
|
|
|
|
|
|
|