摘要 |
The invention relates to an arc melted silica crucible having a polygonal opening, in particular square or rectangular, and its method of fabrication, which comprises preforming the silica powder in a hollow mold having a polygonal opening, said mold being provided with a multiplicity of channels passing through its bottom and its walls, said channels being distributed over its whole internal surface, to constitute a preform, then melting the silica by an electric arc inside the preform, sucking the gases through the mold and the preform, generating a gas speed of at least 0.15 m/second at every point of the inner surface of the preform at the onset of the melting. |