4 results about "Post oxidation" patented technology

The application discloses a sintered neodymium-iron-boron composite coating with high bonding force and high hydrogen resistance and a preparation method thereof. The method comprises the following steps: (a) substrate pretreatment, wherein surface oxides are removed by energy gradient plasma sputtering cleaning; (b) sputtering an Al layer under an Ar atmosphere and oxidizing under O2 plasma assistance, thereby generating an intermetallic compound anchoring layer of FeAl3 / NdAl2 with a thickness of 1.0-1.5 nm in situ; (c) sequentially depositing 6 layers of Al2O3 layers to form an alternating stack with a total thickness of 20-30 nm, wherein the first, third and fifth layers are prepared by directly sputtering an Al2O3 ceramic target, and the second, fourth and sixth layers are prepared by first sputtering an Al layer and then completely converting by O2 oxidation; (d) low-temperature annealing to fully form Al-O-Fe bonds at the interface; and (e) cooling to room temperature. The application adopts a multi-dimensional in-situ closed-loop monitoring system to realize accurate process control, and is suitable for surface protection of sintered neodymium-iron-boron permanent magnets in hydrogen energy equipment.

The application provides a method for improving the white spot defect of a crystalline silicon wafer in a post-oxidation process, which comprises the following steps: (1) wafer loading; (2) first ozone purification; (3) temperature rising; (4) first vacuum pumping; (5) second ozone purification; (6) post-oxidation; (7) second vacuum pumping; (8) pressure recovery; (9) temperature falling; and (10) wafer unloading. The method utilizes ozone with strong oxidizing property to purify the air in a furnace tube, improves the cleanliness of the environment atmosphere in the post-oxidation process, reduces the proportion of pollutants in the furnace tube, and further effectively reduces the proportion of the white spot defect of the crystalline silicon wafer. The method is simple in operation, low in requirement for equipment, low in processing cost, and has a large-scale application prospect.

The application provides a Nb micro-alloyed oriented silicon steel decarburization annealing oxidation layer structure regulation method, and relates to the technical field of oriented silicon steel decarburization annealing. The Nb micro-alloyed oriented silicon steel decarburization annealing oxidation layer structure regulation method comprises the following steps: S1, selecting oriented silicon steel with a Si element mass fraction of 3.0% as a base material, adding Nb element to the base material for micro-alloying treatment, and preparing Nb micro-alloyed oriented silicon steel; S3, placing the Nb micro-alloyed oriented silicon steel prepared in S1 in the decarburization annealing atmosphere prepared in S2 for decarburization annealing treatment, and precisely regulating the thickness of the oxidation layer and the content ratio of spherical oxides to strip-shaped oxides in the oxidation layer after decarburization annealing of the oriented silicon steel by regulating the Nb element addition amount, the decarburization annealing temperature and the holding time. The regulation law of Nb and process parameters on the oxidation layer is clear, the oxidation layer structure is precisely controllable, and the process standardization is supported.

This invention discloses the preparation and application of a highly stable underwater superoleophobic silicon carbide ceramic membrane. The preparation involves first placing an unoxidized silicon carbide ceramic membrane in a muffle furnace and sintering it at 500–900°C for 25–45 minutes to obtain a post-oxidized silicon carbide ceramic membrane. Then, the post-oxidized silicon carbide ceramic membrane is placed in a plasma cleaner and subjected to plasma modification at a vacuum of 300–800 mT for 5–120 minutes. Experiments have shown that the method of this invention produces a silicon carbide ceramic membrane that not only possesses excellent underwater superoleophobic properties but also retains these properties for a long time with high stability, showing great promise for application in oil-water separation. Furthermore, the preparation method of this invention is simple, uses mild conditions, is low-cost, and easily scalable.