Crucible for reappearance of metal-carbon high-temperature eutectic point

Abstract

The invention relates to a crucible for reappearance of a metal-carbon high-temperature eutectic point and belongs to the field of high-temperature thermocouple verification or verification. The crucible is made from graphite and mainly comprises a crucible housing, a crucible lining, a crucible upper cover and a thermometer well. A flange is arranged at the bottom of the crucible lining, and the crucible lining can be directly sleeved with the crucible housing which is located above the flange, so that the mounting is convenient during use. The crucible housing prevents the phenomenon that the crucible lining cracks when the crucible is used at a high temperature so that a metal-carbon eutectic substance flows out, thereby playing a dual protection effect. Meanwhile, when the crucible lining deforms at a high temperature, the bottom of the crucible lining is not restrained by the crucible housing any more, thermal stress is reduced, and the reliability in use of the whole crucible is increased.

Description

technical field [0001] The invention relates to a crucible for reappearing a metal-carbon high-temperature eutectic point, which belongs to the field of high-temperature thermocouple verification or calibration. Background technique [0002] During the verification or calibration of high temperature thermocouples, the quality of the crucible structure design directly affects the final cycle times of the crucible, and indirectly affects the verification times of high temperature thermocouples, so special attention must be paid. [0003] At present, the mainstream crucible has the following two schemes in structural design: [0004] The first type adopts a bottle liner type double-layer shell structure, the inner shell is directly in contact with the metal and carbon (metal-carbon) eutectic, and the outer shell surrounds the inner shell to prevent the inner shell from The role of rupture eutectic leakage, such as Edler et al. in the literature "A cobalt–carbon eutectic fixed ...

AI Technical Summary

Problems solved by technology

The problem with this crucible structure is that there are too many geometric constraints between the inner shell and the outer shell, resulting in the bottom of the inner shell being constrained by the outer shell after thermal deformation at high temperature and prone to extrusion damage

Although this kind of crucible can reduce the risk of inner shell rupture, the graphite braid layer will gradually peel off and separate at high temperature, which will cause certain pollution to the eutectic

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