3results about How to "Uniform and dense microstructure" patented technology

The invention provides a laser vibration cladding device and a method thereof.The device comprises an annular heating cover and an infrared focal plane detector which are arranged in a working cabin with a laser cladding head, and a plurality of independently-controlled infrared heating units evenly distributed in the circumferential direction of the annular heating cover are arranged on the annular heating cover; a workpiece clamping position is arranged below the circle center of the annular heating cover, and the infrared heating units all point to the workpiece clamping position. A multi-channel coaxial powder feeder is further arranged in the working cabin, a plurality of independently-controlled powder bins are integrated in the multi-channel coaxial powder feeder, a powder feeding pipe of the multi-channel coaxial powder feeder is integrated with the laser cladding head, and powder in all channels is converged before entering the powder feeding pipe and conveyed to the laser cladding head through inert gas flow; and an ultrasonic generator, a piezoelectric transducer and a vibration transmission rod are also arranged in the working cabin.

The application provides a kind of anti-freezing high-performance concrete for building 3D printing and a preparation method thereof, the concrete contains cement 80-100 parts by mass, fly ash 80-100 parts, slag powder 220-270 parts, silica fume 15-30 parts, fine aggregate 1200-1500 parts, and polycarboxylic acid high-performance water reducing agent, thickening agent, polypropylene fiber and / or modified cellulose ether, water-binder ratio 0.55~0.67, fine aggregate is natural sand, granite waste sand or mixture thereof, replacement rate 0%~100%. During preparation, accurate measurement, dry mixing, solution preparation, wet mixing fluidization, high-speed slurry, printing forming and moisture curing are carried out. The application adopts microstructure self-optimization active anti-freezing design, without coarse aggregate, which greatly reduces carbon emission, the anti-freezing grade of concrete reaches F125-F150, with excellent printability and mechanical properties, without printing head blockage problem, the preparation process is controllable, and is suitable for building 3D printing engineering in cold and seasonal freeze-thaw areas.

The application discloses a kind of high stability alkali erosion resistant low-grade bauxite-coal gangue based corundum-mullite system of preparation application technology of complex refractory material.Electrofusion magnesia is innovatively introduced into low-grade bauxite-based corundum-mullite system in the application, effectively improving the overall structural stability of the composite material, and a high-performance erosion-resistant composite material with a compressive strength of 89.88 MPa and a bulk density of 3.16 g / cm³ is obtained. And through the modification of zirconium silicate and yttrium oxide, the alkali erosion resistance of the composite material can be greatly improved, so that the material can adapt to the strong alkali working environment of sodium ion battery positive electrode material synthesis, and has excellent comprehensive performance. The application realizes the efficient utilization of low-grade bauxite and coal gangue resources, and the prepared composite material has structural stability and alkali erosion resistance, and can be widely used in high-performance kiln car, furnace lining, crucible and furnace lining, etc. Refractory scene, has good practical value and industrial application prospect.