64results about How to "Good thermal fatigue resistance" patented technology

The invention discloses a high-hardness flux-cored welding wire for overlaying repair of a continuous casting roller, and belongs to the technical field of welding in material processing engineering. An H08A cold-rolled steel strip is adopted as an outer cover, a flux core comprises the following components in percentage by weight: 20-40% of TiO2, 5-15% of high-carbon ferrochrome, 12-30% of low-carbon ferrochrome, 0.5-5% of Mn-Si alloy, 0.5-5% of Al-Mg alloy, 5-15% of Ni, 0.5-2.5% of fluoride, 5-15% of Mo, 0.5-2.5% of V, 2-10% of Cr, 0.5-5% of Al2O3 and the balance of iron powder. The filling rate of the traditional Chinese medicine core of the flux-cored welding wire is 20-35%. The welding wire has the advantages that the flux-cored welding wire adopts a self-protecting overlaying manner, and shielding gas and welding flux are not needed in the overlaying repair process of the continuous casting roller, so that the repair cost can be greatly reduced, the manual labor intensity is lowered, and the production efficiency is improved; the welding wire has good arc stability, excellent abrasion-proof property and excellent thermal fatigue resistant property, and the service life of the continuous casting roller is effectively prolonged.

The invention discloses a grate bar and a preparation method thereof, which belongs to the technical field of heat-resisting materials. The grate bar comprises the following chemical components in percentage by mass: 1.2 to 1.6 percent of C, 15.0 to 20.0 percent of Cr, 2.3 to 2.8 percent of Al, 4.5 to 5.0 percent of Si, 0.05 to 0.15 percent of Ti, 0.05 to 0.15 percent of Nb, 0.08 to 0.20 percent of RE, 0.06 to 0.15 percent of Mg, less than 0.6 percent of Mn, less than 0.04 percent of S, less than 0.05 percent of P and the balance of Fe, wherein the total mass of the Ti and the Nb is more than or equal to 0.20 percent and less than or equal to 0.28 percent. The grate bar of the invention can be produced by electric furnace and is formed by lost foam casting; the grate bar has high strength, high toughness, high inoxidizability and high thermal fatigue resistance, and can be used on large sintering machine trolley for more than 2 years; and when the grate bar is used, the labor intensity of workers can be relieved, the production efficiency of the sintering machine can be improved, and great social and economic benefit can be created.

The invention discloses a high-hardness stainless steel pump valve casting resistant to high-temperature oxidization. The stainless steel casting is balanced in mechanical property, high in hardness, good in toughness, good in heat fatigue resistance, easy to machine and form, good in oxidization resistance in a high-temperature environment and longer in service life. Due to the fact that nano Ca-RE intermediate phase alloy powder carried by honeycomb ceramic powder and composite graphene refining agents are added in molten liquid, the heat stability is good, the material dispersion is more uniform in molten steel, the impurity removal efficiency and the slag melting efficiency are higher, and the purity degree of the molten steel can be effectively improved, so that alloy structure grains are fine and uniform, and the capacity resistant outside negative factors is high ; the casting subjected to heat treatment for multiple times is stable, and the energy-saving and efficient production effect is achieved.

In order to provide a large steel ring that is lighter and thereby contributes to improved fuel consumption, that has lower tensile strength, and has excellent wear resistance and scuffing resistance, and in order to also provide a raw material therefor and a production method for both, a large steel ring having reduced ring width (h1) and radial direction thickness (a1), and having a nominal diameter (d1) of at least 200 mm but less than 1,100 mm is obtained from a hot-forged cylindrical steel material by combining: steel including as compulsory alloy elements C, Si, Mn, and Cr, including as optional alloy elements Ni, V, and Mo, and having the thermal conductivity and/or resistance to thermal degradation thereof adjusted; and hot forging that includes a ring rolling step.

Provided is a ferritic stainless steel excellent in terms of thermal fatigue resistance, high-temperature fatigue resistance and oxidation resistance without adding Mo or W, which is an expensive chemical element and with controlling Nb content to be as small as possible. The chemical composition contains, by mass %, C: 0.020% or less, Si: 3.0% or less, Mn: 3.0% or less, P: 0.040% or less, S: 0.030% or less, Cr: 10% to 25%, N: 0.020% or less, Nb: 0.005% to 0.15%, Al: 0.20% to 3.0%, Ti: 5×(C %+N %) to 0.5%, Mo: 0.1% or less, W: 0.1% or less, Cu: 0.55% to 2.0%, B: 0.0002% to 0.0050%, Ni: 0.05% to 1.0%, and the balance being Fe and inevitable impurities, where C % and N % in the expression 5×(C %+N %) respectively represent the contents (mass %) of the chemical elements C and N.

The invention discloses a high-strength, high-toughness and heat-resistant aluminum alloy material for an internal combustion engine. The aluminum alloy material is prepared from alloy elements in percentage by weight as follows: 9.0%-17.0% of Si, 2.0%-7.0% of Cu, 1.5%-5.5% of Ni, 0.6%-1.5% of Mg, 0.2%-1.1% of Fe, 0.2%-1.1% of Cr, 0.1%-0.3% of Ti, 0.15%-0.5% of B, 0.1%-0.3% of C, 0.08%-0.12% of P,0.4%-0.6% of RE (rare earth) elements, less than or equal to 0.3% of Zr, less than or equal to 0.3% of Sc and the balance Al. The invention further provides a preparation method of the aluminum alloymaterial, wherein briquettes containing B, Ti and Al mixed salt and briquettes containing Ti, Al and C mixed salt directly react in aluminum alloy melt to produce a micro-nano strengthening phase, and then the aluminum alloy material can be prepared.

The invention relates to a roller for a continuous induction type rapid quenching furnace and a manufacturing method of the roller, and belongs to the field of refractory metal powder metallurgy and deformation machining. The roller is made of pure molybdenum or REO doped molybdenum alloy materials, the outer diameter is 400-800 mm, the wall thickness is 15-60 mm, the relative density is not lower than 99.5%, and the tensile strength is not lower than 500 MPa. The manufacturing method comprises the following steps: by taking molybdenum and molybdenum alloy powder which are highly purified by a wet method or are uniformly doped with rare earth oxide by a liquid-liquid or solid-liquid method as raw materials, performing cold isostatic pressing to obtain a ring blank, performing hydrogen high-temperature sintering, performing rough turning, performing ring forging or closed die forging, performing hydrogen annealing treatment, and finally performing precision machining. The roller is uniform in component, high in density, good in strength and toughness and excellent in thermal fatigue resistance, serves as an important component of a large continuous induction type rapid quenching furnace as core equipment for rare earth bonded magnetic powder production, and can be extensively applied to development and production of iron-based soft magnetic amorphous alloy, thermoelectric materials and the like.

The invention provides high-silicon heat-resistant vermicular graphite cast iron with thermal fatigue resistance and high performance and a preparation method of thereof, and belongs to the technicalfield of alloy preparation. The vermicular graphite cast iron comprises the following components of, in percent by mass, 2.50%-3.50% of C, 4.50%-5.50% of Si, less than or equal to 0.30% of Mn, less than or equal to 0.050% of P, less than or equal to 0.020% of S, 0.60%-0.90% of Mo, 0.50%-0.9% of Ni, 0.40%-0.80% of Cr, 0.30%-0.60% of V, 0.20%-0.40% of Nb, less than or equal to 0.20% of Cu, 0.10%-0.20% of Ti, 0.010%-0.020% of Mg, less than or equal to 0.05% of RE, less than or equal to 0.05% of Al, and the balance iron. According to the high-silicon heat-resistant vermicular graphite cast iron with the thermal fatigue resistance and the high performance, various alloy elements are optimally compounded and matched for use, so that the vermicular graphite cast iron has excellent thermal fatigueresistance and high-temperature strength and has good dimensional stability and good heat-conducting capacity at high temperature, and the vermicular graphite cast iron can be used for a CNG vehicleengine turbocharger turbine shell and exhaust pipe. Meanwhile, the vermicular graphite cast iron meeting the requirement of being applied to the CNG vehicle engine is obtained through the preparationmethod of the vermicular graphite cast iron.

The invention relates to a microalloying gray cast iron clutch pressure plate material and a preparation method thereof. The microalloying gray cast iron clutch pressure plate material is composed of, by mass, 3.5%-3.9% of C, 2.2%-2.7% of Si, 0.4%-1.5% of Mn, 0-0.1% of P, 0.06%-0.10% of S, 0.2 %-0.4% of Cr, 0.4%-0.7% of Cu, 0.1%-0.4% of V and the balance Fe. The preparation method comprises the step of compound inoculation treatment of silicon barium and silicon iron. The microalloying gray cast iron clutch pressure plate material is high in toughness, good in heat resistance and excellent in casting performance, and a clutch pressure plate produced through gray cast iron which replaces universally adopted gray cast iron at present meet the development requirements of clutches and even engines in the direction of high efficiency, energy saving and emission reduction and has good application prospects.

The invention relates to the technical field of new material processing and discloses a method for improving the performance of alloy cast iron for an automobile mold. Through the research on the alloy cast iron mold steel structure and material service performance, the low fatigue resistance of the alloy cast iron is solved from internal factors. The comprehensive performance of the mold materialis improved. After the alloy cast iron is smelted into molten iron and poured into a ladle in which the modified silica ceramic powder is placed in advanced, spheroidizing and inoculating are performed. After the reaction is completed, the slag removal purification is performed, and then the pouring forming is performed. In the preparation process of the modified silica ceramic powder, europium oxide and zirconium acetate are used as raw materials, and a rod-shaped nano europium oxide/zirconium oxide composite material is prepared through the reaction; and the nanostructure can prevent intercrystal grain from aggregating and growing and prevent the crack propagation, the good adhesion is shown, and the fatigue of the alloy structure is improved by forming an oxide mass point on the surface of an alloy, so that the prepared mold material has excellent thermal fatigue resistance.

The invention discloses steel for an economical MPM continuous-rolled core rod. The steel comprises, by weight, 0.35%-0.45% of C, 0.8%-1.2% of Si, 0.8%-1% of Mn, 4.8%-5.5% of Cr, 0.3%-0.5% of Mo, 0.1%-0.2% of Ti, 0.02%-0.08% of Nb, 0.002-0.004% of B, 0-0.03% of P, 0-0.02% of S, and the balance Fe and impurities. A manufacturing method of the steel comprises the steps that an electrode rod is smelted; the electrode rod is subjected to electroslag remelting to obtain an electroslag ingot; and the electroslag ingot is heated and forged into a forged blank. According to the steel for the economical MPM continuous-rolled core rod and the manufacturing method thereof, the chemical component proportion of the steel is more economical and cheaper, the Mo content and the V content are decreased, and the alloy cost is greatly reduced; and meanwhile, the mechanical properties of the novel steel are reinforced and ensured by increasing the content of the element Mn and the content of the element Si and adding the microalloy elements of the Ti, the Nb and the B.

The invention discloses a high-temperature-resistant combined type sinking roll which comprises a roller, a roll shaft and two connecting shaft sleeves; the connecting shaft sleeves are of stepped structures; flange plates are arranged at the large ends of the connecting shaft sleeves; spigot holes in the two ends of the roller sleeve and are fixedly connected with the flange plates of the connecting shaft sleeves; external threads are formed in the external circumferences of the flange plates of the connecting shaft sleeves; the spigot holes in the two ends of the roller are internal threadedholes; the external threads in the external circumferences of the flange plates of the connecting shaft sleeves are in internal threaded hole connection with the spigot holes in the two ends of the roller; the roll shaft is of an integral structure axially penetrating through inner holes of the two connecting shaft sleeves, and is fixedly connected with the two connecting shaft sleeves; axial through holes communicating with an inner cavity of the roller are uniformly and circumferentially formed in the flange plates of the connecting shaft sleeves; and the axial through holes in the flange plates of the connecting shaft sleeves at the two ends are formed in the circumferential direction of the center axis of the roller in a staggered manner. As a further improvement, the surface of the roller is coated with a metal ceramic coating. The high-temperature-resistant combined type sinking roll is high in structural strength and rigidity, in the application, when zinc liquid flows throughthe inner cavity of the roller, an eddy flow can be formed uniformly, and the high-temperature-resistant combined type sinking roll is high-temperature-resistant and wear-resistant.

The invention discloses ceramic quenched and tempered steel and a preparation method thereof. The ceramic quenched and tempered steel comprises, by weight, 70-80% of scrap steel, 2-3% of kaolin, 3-5%of bauxite, 3-8% of quartz sand, 1-3% of mica, 1-2% of bentonite, 1-2% of kyanite, 1-2% of barite, 1-2% of calcite, 1-2% of graphite, 1-2% of fluorite, 1-2% of feldspar, 1-2% of mullite, 0.5-1.5% of SiC, 1-2% of zeolite, 1-3% of wollastonite, 1-2% of spinel, 1-2% of crystal, and 1-2% of aluminum magnesium ore. The ceramic high-strength structural steel is prepared by replacing Fe and C main systemmaterials in existing steel with Fe and Si main system nonmetal ceramic materials, and the ceramic high-strength structural steel has good toughness, excellent welding performance, cold forming performance, low cold brittle transition temperature and good corrosion resistance.