- Volume 24 Issue 4
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WO3 Fabrication and Thermal Spray Coating of WC-Co using Recycled Ammonium Paratungstate (APT)
재활용 APT를 이용한 WO3 제조와 WC-Co 의 용사코팅
Chung, J. K.;Kim, S. J.;On, J. H.;Moon, H. S.;Pee, J. H.;Ha, T. K.;Park, S. Y.
- Received : 2015.04.04
- Accepted : 2015.06.02
- Published : 2015.08.01
The possibility of chemical precipitation for recycled ammonium paratungstate (APT) was studied. WO3 particles were synthesized by chemical precipitation method using a 1:2 weight ratio of APT:DI-water. At the 500℃ sintering temperature, the X-ray diffraction results showed that APT completely decomposed to WO3. For the granulated powder WC-Co, vacuum heat treatment at proper temperatures increases tap density and flow-ability. Hardness of the WC-Co thermal spray coating layer was measured in the range HV 831~1266. Spray conditions for the best characteristic values were an oxygen flow rate=1500 scfh, a fuel flow rate = 5.25gph and a gun distance = 320mm.
WO3;APT;Chemical Precipitation;Hard metal;Thermal Spray Coating
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