5results about How to "Prevent decarbonization" patented technology

This invention relates to a steel for automobile engine pistons and its manufacturing method. The chemical composition of the steel, by weight percentage, is: C: 0.41–0.47%, Si: 0.15–0.35%, Mn: 0.70–1.00%, Cr: 1.10–1.40%, P: ≤0.020%, S: 0.015–0.035%, Mo: 0.17–0.27%, Al: 0.010–0.030%, N: 0.0040–0.0060%, with the balance being Fe and unavoidable impurities. The microstructure consists of ferrite and pearlite, with uniform distribution of ferrite and pearlite structures. The geometric center distance between each ferrite and pearlite structure is 15–30 μm. The hot-rolled hardness of the steel is ≤230 HBW, and the banded structure in the steel is ≤1.5 grade. The product features a narrow range of carbon deviation in cross-section, shallow decarburized layer and microcrack depth on the steel surface, low hot-rolled hardness, good banded structure, and high tensile strength after quenching and tempering.

The application discloses a multi-furnace body series connection step-by-step continuous heating furnace, and relates to the technical field of heating furnaces.The heating furnace comprises a furnace loading base, a preheating base is fixedly installed at the rear bottom end of the furnace loading base through bolts, a heating base is fixedly installed at the rear side of the preheating base through bolts, and a furnace loading structure is arranged.The furnace loading structure comprises two fixed support rails which are fixedly installed at the top end of the furnace loading base through bolts.The application is provided with a plurality of furnace bodies, the preheating furnace body is separated from the heating furnace body, the high-temperature flue gas of the heating furnace body is used as the heat source of the preheating furnace body to preheat the steel billet, the flue gas temperature discharged from the preheating furnace body is the final flue gas temperature of the heating furnace body, a small amount of burners can be arranged in the preheating furnace body as auxiliary heating and adjusting burners, the flue gas temperature of the heating furnace can be accurately controlled, the flue gas temperature can be controlled at the lower limit of the anti-dew-point corrosion temperature, the energy consumption is reduced, and the chimney is not corroded.

The invention discloses a full-automatic tilting-type roller carbonitriding furnace, and particularly relates to the technical field of metal material heat treatment, the full-automatic tilting-type roller carbonitriding furnace comprises a processing table, the processing table is provided with a partition wall and a quenching tank, the quenching tank is filled with quenching oil or quenching liquid, the quenching tank is internally provided with a quenching roller mechanism, and the quenching roller mechanism is provided with a quenching roller. A co-permeation heating furnace is arranged at the top of one end of the quenching tank, and a feeding lifting mechanism is arranged between the bottom of the other end of the quenching tank and the partition wall. The roller design with the spiral blades is adopted in the co-permeation heating furnace and the quenching tank, so that the steel balls are in a dynamic rolling state in the heating co-permeation and quenching processes, soft spots generated by traditional static treatment are eliminated, the thickness of a permeation layer is uniform and consistent, the quenching structure is uniform, and the product quality is greatly improved; through the design of the tilting-type furnace body, a high-temperature workpiece can be directly and rapidly transferred into a quenching medium under the protective atmosphere, the workpiece is prevented from being exposed in air, oxidation and decarburization are prevented, and the smoothness and performance of the surface of the workpiece are guaranteed.

This invention discloses a high-wear-resistant high-manganese steel casting and its wear-resistant processing technology, belonging to the field of metal material casting technology. After the casting blank is prepared, the grain boundaries are activated by low-temperature plasma in an oxidation-free atmosphere. A core-shell structured composite nano-pinned phase is generated in situ using segmented temperature and nitrogen control. Then, temperature-controlled micro-deformation and pulsed electric field synergistic solid solution are used to break down and dissolve the network carbides at the grain boundaries. Combined with carbon potential stabilization, gradient cooling quenching, homogenization of the composite pinned phase, and low-temperature stress relief treatment, the microstructure of the casting is precisely controlled. This invention solves the technical contradiction of the difficulty in synergistically improving the hardness and toughness of traditional high-manganese steel, overcoming the technical problems of insufficient wear resistance, easy coarsening of the microstructure at high temperatures, and high internal residual stress. The resulting casting exhibits uniformly dispersed grain boundary strengthening phases, possessing high hardness, high wear resistance, high impact toughness, and excellent high-temperature stability.

This utility model discloses a roller hearth type protective atmosphere bright solution furnace that effectively isolates oxidizing atmospheres. The roller hearth type protective atmosphere bright solution furnace of this utility model includes, along the material flow direction, a gas exchange section, a heating section, a rapid cooling section, and a slow cooling section that are interconnected. The gas exchange section includes a sealing section and a preheating section connected in sequence. The preheating section is connected to the heating section. The top of the sealing section and / or the preheating section is equipped with several isolation boxes that isolate the oxidizing atmosphere by sealing the steel with sealant.