120results about How to "Guaranteed hardenability" patented technology

The invention discloses a disk-shaped roller cutter ring with high hardness, good toughness and excellent comprehensive performance. The disk-shaped roller cutter ring comprises the following ingredients of: 0.46-0.56% of C, 0.80-1.20% of Si, 0.20-0.65% of Mn, 5.00-5.80% of Cr, 1.15%-1.55% of Mo, 0.85-1.40% of V and the balance Fe and impurities, wherein the content of P is no more than 0.02%, and the content of S is no more than 0.01%; and the overall hardness of the cutter ring is HRC55-61 (Rockwell Hardness C55-61), or the hardness is of graded distribution, i.e. the hardness of a working edge area is HRC55-61, the hardness of a transition surface area is HRC50-57, and the hardness of a step assembly surface area and an inner ring is HRC44-51. A preparation method of the disk-shaped roller cutter ring comprises the following steps of: smelting the raw materials in an electric furnace; carrying out electroslag remelting; preforging; carrying out die forging; carrying out slow cooling; annealing; carrying out rough machining to obtain a disk-shaped roller cutter ring rough blank; carrying out high-temperature vacuum hardening and two-time high-temperature tempering on the cutter ring rough blank; carrying out low-temperature destressing treatment; carrying out fine finishing to obtain the cutter ring with the overall hardness of HRC55-61, wherein the cutter ring with the overall hardness of HRC55-61 is applicable to the tunneling of a hard rock formation by a shield tunneling machine; or carrying out medium-frequency induction tempering treatment prior to the low-temperature destressing treatment to obtain the cutter ring with graded-distribution hardness, wherein the cutter ring with the graded-distribution hardness is applicable to the tunneling of a rock formation with an upper soft part and a lower hard part.

The invention discloses an economical non-quenched and non-tempered micro-alloyed plastic die steel plate and a making method thereof. The economical non-quenched and non-tempered micro-alloyed plastic die steel plate comprises 0.32-0.40wt% of C, 0.20-0.50wt% of Si, 1.00-1.50wt% of Mn, 1.20-1.70wt% of Cr, 0.20wt% or less of Mo, 0.0025wt% or less of B, 0.03wt% or less of Ti, 0.03wt% or less of Nb, and the balance Fe. The making method comprises the following steps: carrying out converter smelting, LF+RH refining and continuous slab casting; heating the obtained slab at 1200-1230DEG C, carrying out precision rolling at 900-950DEG C, and carrying out finishing rolling at 870-920DEG C; carrying out controlled cooling after the steel plate rolling; and tempering the steel plate obtained after the controlled rolling and controlled cooling at 550-600DEG C to obtain the finished pre-hardened plastic die steel plate having a bainite structure. The yield strength, the normal temperature impact toughness and the cross section hardness of the steel plate are above 800MPa, above 20J and 310-350HB respectively. The making method is suitable for the production of pre-hardened plastic die steel plates with the specification of below 120mm from 320mm continuous casting blanks.

The present invention relates to one kind of cast steel for bearing parts in mechanical lifting system and its making process. The cast steel of Cr-Ni-Mo line consists of C 0.15-0.30 wt%, Mn 0.60-1.10 wt%, Si 0.3-0.8 wt%, Ni 0.4-1.1 wt%, Cr 0.4-1.1 wt%, Mo 0.15-0.40 wt%, S less than 0.025 wt%, P less than 0.025 wt%, and residual elements including Cu, W and V less than 0.60 wt%. The making process of the cast steel includes the following technological steps: making steel in MF furnace or electric arc furnace; casting in sand mold with equivalent circular kiel test rod; normalizing, quenching and tempering of both cast part and test rod in the same furnace; and non-destructive detection of the cast part.

The invention relates to steel for a low-carbon wear-resistant engineering machinery creeper tread and a manufacturing method thereof. The steel comprises the following chemical components in percentage by weight: 0.17-0.27 percent of C, 0.17-0.37 percent of Si, 0.85-1.20 percent of Mn, 0.10-0.30 percent of Cr, 0.010-0.060 percent of Al, 0.010-0.20 percent of Cu, 0.01-0.20 percent of Ni, 0.003-0.025 percent of P, 0.001-0.025 percent of S, 0.020-0.060 percent of Ti, 0.0005-0.0035 percent of B, 5-20*10<-6> percent of [O], 40-90*10<-6> percent of [N] and the balance of Fe and inevitable impurities. The manufacturing method adopts an electric furnace for smelting and making steel, an LF furnace for external refining and VD for vacuum degassing treatment. The steel and the manufacturing methodhave excellent technical effects.

The invention provides high-performance ocean platform steel and its production method. When the thickness of a steel plate is 8-40mm, the steel plate is composed of the following chemical components, by weight, 0.11-0.13% of C, 0.20-0.50% of Si, 1.45-1.55% of Mn, 0.012% or less of P, 0.003% or less of S, 0.035-0.045% of V, 0.025-0.030% of Nb, 0.050% or less of Ti, 0.020-0.050% of Al, and the balance Fe and inevitable impurities; and when thickness of a steel plate is 40-100mm, the steel plate is composed of the following chemical components, by weight, 0.10-0.12% of C, 0.20-0.50% of Si, 1.50-1.60% of Mn, 0.012% or less of P, 0.003% or less of S, 0.070-0.075% of V, 0.030-0.040% of Nb, 0.050% or less of Ti, 0.020-0.050% of Al, and the balance Fe and inevitable impurities. The production method of the steel plate of the invention comprises the steps of electric furnace smelting, LF furnace refining, VD vacuum treatment, continuous casting (or die casting), heating, control rolling, cooling, stacking, and normalizing to prepare the steel plate. Through a reasonable component design and process optimization, the steel plate of the invention has excellent mechanical performances, welding performances and processing performances, and has strong market competitiveness.

The invention relates to a kind of cold-rolled hot-galvanized complex phase steel. Chemical components of the cold-rolled hot-galvanized complex phase steel comprise, by weight, 0.05-0.13% of C, 0.1-0.5% of Si, 1.5-2.5% of Mn, less than or equal to 0.015% of P, less than or equal to 0.015% of S, 0.1-0.6% of Al, 0.2-0.6% of Cr, 0.1-0.5% of Mo, 0.01-0.06% of Nb, 0.01-0.06% of Ti, and the balance Feand inevitable impurities. The invention further relates to a preparation method of the cold-rolled hot-galvanized complex phase steel. The preparation method comprises the following steps of castingmolten steel into a steel billet; conducting hot rolling on the steel billet to obtain a hot-rolled plate and conducting cold rolling on the hot-rolled plate to obtain a cold-hardened steel strip; conducting continuous galvanizing and annealing process treatment on the cold-hardened steel strip to obtain a finished cold-rolled hot-galvanized complex phase steel product. The bending performance ofthe cold-rolled hot-galvanized complex phase steel is improved on the basis of meeting the requirement for strength.

The invention discloses a high-grade wear-resistant steel plate. The steel plate comprises the following components in percentage by mass: less than or equal to 0.26 percent of C, less than or equal to 0.50 percent of Si, less than or equal to 1.60 percent of Mn, less than or equal to 0.015 percent of P, less than or equal to 0.005 percent of S, 0.10 to 0.30 percent of Ni, less than or equal to 1.50 percent of Cr, less than or equal to 0.06 percent of Nb, 0.02 to 0.06 percent of Al, less than or equal to 0.03 percent of Ti, less than or equal to 0.50 percent of Mo, less than or equal to 0.08 percent of V, less than or equal to 0.004 percent of B, and the balance of Fe and inevitable impurities. A method for producing the steel plate comprises smelting, casting, heating, rolling, straightening, shot blasting, quenching, heat treatment, cutting and other process steps. The steel plate has the advantages of steel purity, high strength, high hardness, good low temperature toughness, good weldability, good processability, good cold bending property, large steel plate thickness, good plate cut, little noble metal added to the steel plate and low cost. The steel plate can be widely used in the industry of manufacturing mining, engineering, metallurgical and other machinery with broad application prospects.

The invention relates to a 135 steel-level drill rod connector and a heat treatment process thereof. The drill rod connector comprises the following components in percentage by weight: 0.25-0.32 percent of C, 0.30 percent of or less Si, 0.35-0.80 percent of Mn, 0.015 percent of or less P, 0.008 percent of or less S, 0.15-0.80 percent of Mo, 0.00-1.00 percent of Ni, 0.90-1.50 percent of Cr, 0.30 percent of or less Al, 0.05 percent of or less Nb, 0.10 percent of or less V and the balance of Fe and unavoidable trace elements. The heat treatment process comprises the steps of: heating a roughly processed connector blank to 920-960 DEG C from the room temperature, preserving heat for 0.5-1.5 hours, putting the connector blank into a high-grade oil base quenching medium at 30-50 DEG C, fully cooling the connector blank, then heating the connector blank to 550- 620 DEG C from the room temperature for 50-70 minutes, preserving heat for 1.5-2.5 hours, and then discharging the connector. After heat treatment, the mechanical performances are as follows: the yield strength is 140-160 Ksi (965-1100 MPa), the elongation percentage is larger than or equal to 17 percent, the drill rod connector is longitudinal and is at 20 DEG C below zero and has full size, and the charpy impact energy is higher than or equal to 100 Joules.

The present invention relates to a high-performance hydrogen sulfide corrosion resistant petroleum drill pipe with a weight percentage of components as follows: C 0.20-0.32 percent, Si 0.1-0.5 percent, Mn 1.0-1.5 percent, Cr 0.5-1.5 percent, Mo 0.8-1.2 percent, P less than or equal to 0.015 percent, S less than or equal to 0.01 percent and the remainders are Fe and unavoidable impurities. The drill pipe of the present invention has a higher content of Mn, which can guarantee an upset end with a thickness of over 30mms to be fully hardened, thereby guaranteeing the sulfur-resistant performance of the upset end. The drill pipe of the present invention has a higher content of Mo, which can improve the backfire-preventive stability of the material, thereby raising the backfire temperature, reducing the residual stress and guaranteeing the sulfur-resistant performance. Simultaneously, the invention can make the pipe body with a different wall thickness and the upset end have the same cooling speed by controlling the outer water injection of the upset end and pipe body of the steel pipe, reducing the water injection outside the pipe body or increasing the water injection outside the upset end of the drill pipe, to ensure that the pipe body and the upset end have the same quenching structure, and the same mechanical property can be achieved after the backfire.

This invention relates to a MnCu alloy ADI car rear axle screw bevel gear and its preparation method, which takes ordinary pig iron as the raw material of said gear, applies a duplex method of cupola and electric cooker, takes rear earth, Mg and silicon iron alloy as the nodulizer to be processed then to slag and eliminate slag, gestates and casts the gear roughcast in two times, then finishes it after mechanical process, isothermal quenching and temper, in which, the composed weight percentage of said gear is: C 3.4-3.8%, Si 2.4-2.9%, Mn 0.4-1.0%, Cu 0.5-1.2%, P less than 0.06%, S less than 0.02% and the rest is iron.

The invention discloses a non-annealed cold forging steel hot-rolled wire rod and a production method thereof. The method comprises the steps of continuous casting, heating, rolling, spinning and cooling. The non-annealed cold forging steel hot-rolled wire rod comprises 0.29-0.38wt% of C, 0.15-0.30wt% of Si, 0.70-0.90wt% of Mn, 0.03wt% or less of P, 0.03wt% or less of S, 0.30wt% or less of Cr, 0.0008-0.0050wt% of B, and the balance of Fe and residual elements. In the heating step, continuous cast billets are heated to 1100-1190DEG C; in the rolling step, the initial finish rolling temperature is 965-995DEG C; in the spinning step, the spinning temperature is 960-990DEG C; and in the cooling step, the cooling speed is 0.5-1.5DEG C/s. The method realizes production of the non-annealed cold forging steel hot-rolled wire rod through optimally designing chemical components, controlling the heating temperature, the initial finish rolling temperature, the spinning temperature and the cooling speed and controlling the amount and the grain size of ferrite by using present devices and technologies without increasing investment or production cost, so the non-annealing production and cost reduction demands of downstream users are met, and pollution of annealing to environment is avoided.

The invention discloses an intermediate-carbon high-speed cutting saw blade matrix steel and a production method thereof. The steel comprises the following components in percentage by weight: 0.20-0.40% of C, 0.10-0.30% of Si, 0.45-0.63% of Mn, not more than 0.010% of P, not more than 0.005% of S, 0.008-0.020% of Ti, 0.80-1.20% of Cr, not more than 0.005% of N, 0.020-0.050% of Al, 0.10-0.20% of Ni, 0.030-0.050% of V and the balance of Fe and inevitable impurities, wherein Als/N is not less than 30%, Mn +Cr is 1.45-1.85. The production method comprises the following steps of: desulfurizing molten iron, smelting in a converter, carrying out vacuum treatment, casting continuously, hot-rolling continuously, cooling, coiling, leveling, quenching and tempering. Facts prove that the steel has pure steel quality, strong toughness, high wearing resistance and low cost at the same time. The production method of the steel is simple in process and stable in product property.

The invention discloses a steel tube used for a hollow stabilizer bar of an automobile and a manufacturing method of the steel tube. The steel tube is prepared from the following chemical components in mass percent: 0.28 to 0.40 percent of C, 0.05 to 0.35 percent of Si, 1.05 to 1.60 percent of Mn, 0.1 to 0.6 percent of Mo, 0.001 to 0.006 percent of B, 0.015 to 0.060 percent of Al, 0.1 to 0.8 percent of Cr, 0.003 to 0.06 percent of Ti, not greater than 0.006 percent of S, not greater than 0.015 percent of P, not greater than 0.003 percent of O and the balance Fe and other inevitable impurities,wherein Mo+50B+Cr is not less than 0.7 percent but is not greater than 1.3 percent. The steel tube disclosed by the invention is high in strength and plasticity, has high torsion fatigue resistance under a relatively high stress level, and can meet the using requirement of the stabilizer bar under a high-stress condition; and the specific performance indexes are shown as follows: as-quenched tensile strength is not less than 1700 MPa, as-quenched yield strength is not less than 1300 MPa, as-quenched ductility is not less than 12 percent, inner surface decarburization depth and outer surface decarburization depth are both 0, and under the condition of 550 MPa, the number of times of torsion fatigue is greater than 1200000.

The invention relates to a low-cost manufacturing method for a high-intensity quenched and tempered steel plate and belongs to the technical field of metallurgy. Ingredient design of the manufacturing method is based on a traditional quenched and tempered high-intensity steel plate, valuable alloy elements such as Ni, Mo, Cu, Nb and V are not required, the valuable alloying elements are greatly saved, alloy cost is greatly reduced, the cost advantage is remarkably improved, and the economic benefit is obvious. The ingredient design can be combined with four different tempering processes to respectively produce products meeting the performance requirements of 6-60mm and 600-800MPa intensity-level high-intensity steel. A process window is wide, process adaptability is wide, and one-steel multi-stage flexible manufacturing is achieved.

The invention discloses a high-toughness spring steel and a preparation method thereof. The spring steel comprises the following alloy components by weight percent: 0.27-0.32% of C, less than or equal to 0.30% of Si, 0.80-1.20% of Mn, 0.30-0.50% of Cr, less than or equal to 0.25% of Ni, less than or equal to 0.30% of Cu, less than or equal to 0.035% of S, less than or equal to 0.035% of P, the balance of Fe, and inevitable impurities, and the alloy component of the spring steel also comprises B being less than or equal to 0.0035%. The preparation method comprises the following steps of a. collecting, screening and sorting waste steel; b. proportioning materials and feeding the materials into a furnace according to component requirement of the primary refining of the type of the steel; c. smelting in an intermediate frequency furnace; d. melting down, slagging off and sampling; e. alloying through partial deoxygenation in the intermediate frequency furnace; f. slag-free tapping; g. deoxidizing in a ladle, and manufacturing ladle refining slag; h. refining in a finery; i. staying the ladle and soft blowing; j. pouring molten steel under the full protection of a conticaster; k. collecting the finished product; l. pile cooling, and slowly cooling for 24 hours; and m. coating color codes of the type of the steel. The high-toughness spring steel has better toughness and hardenability, the lower limit carbon content is improved to 0.27% so that the hardenability of the steel is guaranteed, and the property of a leaf spring is guaranteed.

The invention provides a manufacturing method of a seamless steel pipe for a long pipe trailer gas cylinder with a diameter of 920mm, and belongs to the manufacturing technology of large diameter seamless steel pipes. The manufacturing method comprises the steps that the chemical composition of seamless steel pipe materials is optimized, and the hardenability of the composition is improved; afterusing a 820 cross rolling mill to pierce, a waste pipe is rolled, a jacking type hot expanding unit is used for expanding the diameter, a hydraulic type straightening machine and a six-roll straightening machine are used for two-step straightening and rounding, and a precision cold drawing unit is used for two cold pullout. According to the manufacturing method of the seamless steel pipe for the long pipe trailer gas cylinder with the diameter of 920mm, the manufacturing cost is low, the material utilization rate is high, and the mode of production is flexible; and moreover, the phi 920mm seamless steel pipe manufactured by the method has high geometric accuracy, good internal and external surface quality, good hardenability and high comprehensive performance, and the range of the actual weight of a finished product exceeding the theoretical weight does not exceed 7.5%.

The invention discloses steel for a large-sized wind power fastener. The steel is prepared from the element components in percentage by mass: 0.38-0.45% of C, 0.20-0.35% of Si, 0.60-0.80% of Mn, lessthan or equal to 0.015% of P, less than or equal to 0.010% of S, 0.95-1.20% of Cr, 0.18-0.30% of Mo, 0.10-0.25% of Ni, 0.02-0.08% of Nb, 0.020-0.050% of Al, less than or equal to 0.008% of N, and thebalance of Fe and inevitable impurities. After heat treatment, the core part of the steel is provided with 90% or above of a martensitic structure, the surface hardness difference of the core part isless, especially the low-temperature impact property is excellent, the good mechanical properties are achieved, the tensile property meets the 10.9-grade strength requirements, and the machining usingrequirements for the steel for 48-65 mm of the large-sized wind power fastener by a user can be met.

The invention belongs to the technical field of hot working of section-variable aluminum alloy die forgings, and in particular relates to a hot working method for improving the structure and the performance of a section-variable aluminum alloy die forging. The method is characterized in that a moulding bed is designed and made according to the section-variable structure of the aluminum alloy die forging; a blank is separated and shaped by using the moulding bed; a preforging die is designed and made according to the section-variable profile of the aluminum alloy die forging; the preforging die is dimensioned to have a certain deformation allowance for the next forging; the blank is preforged by the preforging die, so that the blank is fixed and locally machined through the perforging die and each variable section is uniform in deformation; a final forging die is designed and made according to the final size of the variable sections of the aluminum alloy die forging; and forming and forging of the blank are conducted by the final forging die. The method enables the sections of all parts of the section-variable aluminum alloy die forging to be consistent, so that the hardenability of heat treatment and the uniformity of the structure property are guaranteed, and the whole performance of the section-variable aluminum alloy die forging is largely improved.