3results about How to "Avoid oxidation burn" patented technology

The present application relates to the field of energy-saving and environment-friendly production technology, in particular to a calcination method and system for flow-suspension roasting of petroleum coke. The method comprises: feeding petroleum coke raw materials into a multi-stage preheating system for countercurrent preheating; after preheating, the materials enter a flow-suspension roasting furnace to form a suspension state in a high-temperature airflow for rapid roasting; after roasting, the materials are separated from the flue gas, the separated flue gas containing volatile components is combusted in a combustion furnace and then subjected to purification treatment, and the heat is partially recycled; the separated high-temperature calcined coke is cooled through an air cooling and water cooling system and the heat is recovered, and the hot air generated by air cooling is recycled to the roasting furnace. The present application uses fluidization technology to shorten the roasting time to seconds, significantly improving the production efficiency; through multi-stage countercurrent heat exchange, flue gas combustion and heat recycling, the present application realizes heat cascade utilization and precise atmosphere control, greatly reduces energy consumption and oxidation loss, and stably controls the volatile component of the product below 1%, with high yield and uniform quality.

The application provides a rare earth-titanium-boron composite vacuum seal welding high-density cored wire and a preparation method thereof, and belongs to the technical field of metallurgical auxiliary materials. The preparation method comprises the following steps: weighing lanthanum-cerium rare earth alloy powder, titanium powder and boron powder for batching, and then uniformly mixing under a protective atmosphere to obtain mixed powder; filling the mixed powder into a low-carbon steel cylinder after pretreatment under a protective atmosphere, and then preliminarily sealing to obtain a composite blank; performing a reduction reaction on the composite blank in hydrogen, and then performing seal welding under a vacuum condition to obtain a composite blank after vacuum seal welding; heating the composite blank after vacuum seal welding, and then performing hot drawing to obtain the cored wire. The cored wire provided by the application realizes stable composite addition of rare earth, titanium and boron with high recovery rate, and significantly improves the structure and performance of 20Mn2 steel and the like, and solves the problems of cold heading cracking, insufficient toughness and aging embrittlement.

The application relates to the technical field of alloy materials, in particular to a 4341E high-speed steel and a preparation method thereof. The high-speed steel is characterized in that Ti, B and N elements are introduced for ternary micro-alloying and synergistic modification on the basis of a W-Mo-V-Co component system, nanoscale particles generated in-situ by Ti-N are used as heterogeneous cores to significantly refine grains, the grain boundary is strengthened by the grain boundary segregation effect of boron elements, and the reticular carbide is effectively broken. The obtained steel material realizes perfect matching of high hardness, excellent red hardness and excellent impact toughness, solves the problem that the strength and toughness of traditional high-speed steel are difficult to be compatible, and is particularly suitable for manufacturing high-performance cutting tools, cold and hot precision dies and high-temperature wear-resistant parts.