2results about How to "Uniform temperature gradient" patented technology

The invention relates to the technical field of precious metal metallurgy, and discloses a high-density iridium ingot sedimentation type smelting process which comprises the following steps: preparing a water-cooled copper crucible with a zirconium oxide inner wall coating; iridium powder and calcium oxide powder are mixed and put into a crucible; performing induction heating in a vacuum environment until the raw materials are molten; protective gas is inflated, periodic variable-pressure oscillation operation is applied under the condition that the temperature of the melt is kept, and slag crust on the surface of the melt is destroyed through pressure fluctuation and deep gas is promoted to be exhausted; after oscillation is stopped, the melt is left to stand, and a slag system floats upwards and is separated; and establishing a bottom-to-top temperature gradient to control directional solidification of the melt. According to the invention, oxide hard shells are destroyed through a variable-pressure oscillation mechanism, and efficient degassing and impurity removal are realized by cooperating with calcium oxide slagging; the zirconia coating effectively prevents the crucible material from being polluted; the directional solidification and hot isostatic pressing process eliminates internal shrinkage cavities and looseness. According to the process, the impurity content in the iridium ingot is remarkably reduced, and the purity and compactness of the material are improved.

This invention relates to the field of crystallizer technology and discloses a continuous scraper crystallizer with a single water-cooling path. It includes a crystallizer shell, inside which multiple cooling plates are fixed. Each cooling plate has a cooling water flow channel, and adjacent cooling plates are connected in series via connecting pipes. An air-cooled box is installed at the top of the crystallizer shell, and the top portion of the connecting pipe extends into the air-cooled box. A stirring shaft is rotatably mounted inside the crystallizer shell, driven by a rotary motor. A stirring and scraping crystallization mechanism is installed on the outside of the stirring shaft at a position corresponding to the cooling plate. This invention, due to its single cooling water path, provides a uniform temperature gradient, excellent crystallization effect, and high product purity and yield. The inner wall of the crystallizer shell is rigorously polished to ensure a roughness ≤0.1nm, virtually eliminating wall adhesion and facilitating smoother production.