Multiphase nitride combined silicon carbide ceramic foam filter and preparation method thereof

Abstract

The invention relates to a multiphase nitride combined silicon carbide ceramic foam filter and a preparation method thereof, and belongs to the technical field of refractory materials. The preparation method is realized in a way as follows: preparing slurry from silicon, silicon carbide, silicon dioxide, ball clay, admixtures and water; soaking the slurry by using soft polyurethane foam as the carrier to prepare a blank; and drying, and sintering at 1400-1500 DEG C in the nitrogen atmosphere to obtain the multiphase nitride combined silicon carbide ceramic foam filter. The ceramic foam filter of the invention has favorable high temperature stability in ferric and copper solutions, does not pollute alloys, has the open-cell rate of 80-90%, has favorable filtration and adsorption capacities on oxide inclusions and flux inclusions, and has the advantages of high filter capacity, favorable filtration and purifying effect, small hot melt and high thermal shock stability; the compression strength at normal temperature is not lower than 2.3 MPa; the ceramic foam filter can be cooled by water at 1100-20 DEG C for more than 23 times, and does not need preheating in use; and the highest service temperature is 1550 DEG C.

Description

technical field

[0001] The invention relates to the purification of molten metals, in particular to foam ceramic filter technology, more specifically the invention relates to a multiphase nitride-bonded silicon carbide foam ceramic filter for cast iron and cast copper. Background technique

[0002] The slag inclusions in the metal melting process and the pores generated in the casting process account for a large proportion of casting defects. In casting production, the casting rejection rate caused by non-metallic inclusions is generally as high as 50% to 60% of the total number of rejects, and the use of foam ceramic filters to filter molten metal can reduce 60% to 80% of slag and impurities. Scrap, meanwhile, the mechanical properties and machinability of filtered castings have been significantly improved.

[0003] At present, in foreign countries, there are already some companies in developed countries engaged in the production of silicon carbide foam ceramic filters for...