Si3N4 composite ceramic preparation with kerf loss silicon powder from photovoltaic industry by molten salt assisted nitriding method
Listed in
This article is not in any list yet, why not save it to one of your lists.Abstract
In this paper, Si 3 N 4 composite ceramic were synthesized with kerf loss silicon waste powder as the raw material by molten salt assisted nitridation method. Na 3 AlF 6 molten salt was introduced into the system and the effects of Si-salt ratio, nitridation temperature on the nitriding product were investigated. These results indicated that the addition of Na 3 AlF 6 promotes the conversion of waste silicon to Si 2 N 2 O, and 90.7% of Si 2 N 2 O phase was obtained with the Si-salt ratio of 1:1.5 at 1350℃. The increase in temperature causes the main phase of the product changes from Si 2 N 2 O to β-Si 3 N 4 , which is due to the decomposition of Si 2 N 2 O and the α→β phase transition of Si 3 N 4 . And the content of β-Si 3 N 4 phase reached 72.9% with the Si-salt ratio of 1:0.75 at 1450℃. The formation mechanism was analyzed combined with the in-situ nitriding process.
