| abstract |
The invention provides a fire-clay crucible (8) capable of reacting thermal stress and being suitable for melting alloy with high activity, which is provided with a surface coating part (16), a backing (22), and at least one retaining ring (30), wherein the retaining ring (30) is used for winding at least one part of the backing (22) of a crucible (8) and comprises the following components: conducting material, non-conducting material and the components selected from the combination of the two materials. |