10results about How to "Prevent decarbonization" patented technology

The invention provides salt-spray-resistant steel, a preparation method and application of the salt-spray-resistant steel. The salt-spray-resistant steel sequentially comprises an alloy matrix, a permeable layer and an anti-corrosion coating from inside to outside. The alloy matrix comprises an Fe element; the permeable layer comprises Fe, N and O elements; the anticorrosive coating covers at least the surface of the permeable layer. The steel has the characteristics of high strength and salt spray resistance, the binding force of the coating and a matrix is good, the thickness of the anti-corrosion coating is greatly reduced under the condition that the anti-corrosion requirement of the CX grade is met, the machinable performance of a workpiece is effectively improved, and the adverse effects that the workpiece meshing force is poor, and the surface is not uniform due to the thick coating are avoided.

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 utility model discloses a three-pin type universal joint cold finishing die which comprises an upper die and a lower die which is coaxially installed and located below the upper die, and further comprises a discharging mechanism and a discharging mechanism which are installed on the lower die. After the upper die carries out the extrusion process on a forge piece placed in the lower die, the upper die unloads the forge piece arranged on the upper die in a sleeving mode through the unloading mechanism when returning and resetting are carried out on the upper die, the unloaded forge piece is sent out of the lower die through the discharging mechanism, and a universal joint obtained through machining of the die reduces metal deformation resistance, is high in precision and good in surface quality and has good machining performance. And the procedure of machining the cup-shaped part is omitted, so that the production efficiency is greatly improved.

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 processing technology for preventing decarburization of a bearing steel pipe, which can effectively prevent the decarburization behavior of the bearing steel pipe in a furnace heating process, can effectively reduce the thickness of a decarburized layer of the bearing steel pipe, and further improves the surface performance of the bearing steel pipe. An anti-decarburization coating is prepared on the surface of the blank, so that an isolation protection layer can be effectively formed on the surface of the blank, and the decarburization reaction of the blank in the furnace heating process is avoided; it can be guaranteed that the coating is non-toxic and does not pollute the environment in the heating application process; according to the coating design, the complete sealing performance of self protection of the coating in the whole heating process can be guaranteed, and the coating design does not affect the internal quality of grains, structures and the like of the bearing steel pipe; the design of the coating can ensure that the coating can be basically completely peeled off after being discharged from a heating furnace and subjected to water descaling, so that the surface quality of the bearing steel pipe billet is prevented from being influenced.

The invention discloses a material for a high-performance injection mold and a preparation method of the material. The material comprises the following components in percentage by mass: 0.30-0.40% of C; 0.20% to 0.40% of Si; mn: 1.2 to 1.5%; 1.5 to 2.0 percent of Cr; 1.5 to 2.0 percent of Mo; 0.8% to 1.2% of Ni; 0.2 to 0.4 percent of V and the balance of Fe. According to the material for the injection mold, alloy elements such as Ni, Mo and V are added on the basis of medium carbon steel during burdening, crystal grains are refined, the hardenability is improved, and meanwhile the strength, wear resistance and plasticity and toughness of the material are improved. Ni and Cr alloy elements are also beneficial to improving the corrosion resistance of the injection mold.

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.

The invention relates to the technical field of alloy materials, in particular to a preparation method of a long-service-life molybdenum alloy plug and the molybdenum alloy plug prepared through the preparation method. Rare earth oxide powder, titanium hydride powder, zirconium hydride powder, carbon powder and molybdenum powder are subjected to wet grinding and mixing, and after drying and sieving, needed alloy doped powder is obtained; and carrying out cold isostatic pressing and multi-section atmosphere sintering to obtain the molybdenum-alloy-doped plug. According to the preparation method, the carbon potential in the sintering furnace is controlled by adopting a segmented sintering process and controlling the sintering atmosphere, and the molybdenum alloy plug with excellent performance and long service life is prepared. The plug manufactured through the method has many carbide phases on the surface layer and high surface strength and hardness, and the method has the advantages of being easy and convenient to operate and low in cost.