35results about How to "Guaranteed ferrite content" patented technology

The invention discloses a more than 630MPa level high strength steel bar comprising the following components: by weight, 0.28%-0.38% of carbon, 0-0.35% of silicon, 0-0.90% of manganese, 0.80%-1.50% of Cr, 3.00%-4.00% of nickel, 0.40%-0.60% of molybdenum, 0-0.015% of P, 0-0.015% of sulfur, 0-2.0ppm of hydrogen, 0.10%-0.20% of vanadium, 0-0.025% of titanium, 0-0.20% of copper, 0-0.05% of aluminum, 0-0.50% of residual elements and the balance of Fe; the invention also designs an application method of the more than 630MPa level high strength steel bar in reinforced concrete; and the more than 630MPa level high strength steel bar has the advantages of high strength, steel saving, no pollution, good hardenability, low tendency to crack and low relaxation degree.

The invention discloses a processing method of an above-600MPa-grade high-strength steel bar connection sleeve. The sleeve selects No.45 round steel as a raw material, and the No.45 round steel comprises 0.38-0.43wt% of C, 0.8-1.1wt% of Cr, 0.75-1.0wt% of Mn, 0.15-0.25wt% of Mo, 0.15-0.3wt% of Si, below 0.035% of S, below 0.035wt% of P, below 0.035wt% of N, and the balance Fe. The designed processing method of the above-600MPa-grade high-strength steel bar connection sleeve substantially improves the tensile strength and the elongation rate, guarantees the external diameter dimension and fineness of a steel tube, and reduces the friction stress between a tap and the inner wall of the sleeve.

The invention discloses a making method of an alloy coat coated prestressed steel wire. The method comprises the following steps: 1, preparing an alloy coat which is powdery; 2, sequentially carrying out pickling treatment phosphatization treatment and surface drying treatment of a prestressed steel wire rod; 3, sending the above obtained treated prestressed steel wire into a drawing machine, drawing to obtain the prestressed steel wire having required specifications and dimensions, and cleaning the prestressed steel wire; 4, sending the prestressed steel wire into a hot spraying device, uniformly spraying the surface of the prestressed steel wire with the prepared alloy powder by a spray gun, allowing the sprayed prestressed steel wire to an intermediate frequency heating furnace, and heating the prestressed steel wire to 550-570DEG C within 5-8s; and 5, allowing the prestressed steel wire to enter a quenching cooling device, cooling through a second cooling operation, air-cooling to room temperature, allowing the prestressed steel wire to a take-up machine, examining, and warehousing to obtain the alloy coat coated prestressed steel wire. The method increases the strength of the prestressed steel wire, further improves the wear resistance and the corrosion resistance of the prestressed steel wire, and prolongs the service life of the prestressed steel wire.

The invention discloses a treatment process of an aluminum-clad metal wire for high-strength shelf back mesh. A selected steel blank comprises the following chemical components in percent by weight: 0.03-0.08% of C, 0.20-0.30% of Si, 0.20-0.46% of Mn, 0.85-1.0% of Cr, 0.16-0.22% of Mo, 0.015-0.030% of N, 0.05-2% of Cu, 0.02-0.10% of Ce, 0.02-0.10% of La, 0.04-0.05% of P, 0.03-0.04% of S, 0.01-0.25% of Nb, 0.18-0.36% of V, 4.8-5.9% of Al and the balance of Fe and impurities. During sectional material processing, the working procedures including feeding, drawing, electroplating, annealing, heat preserving, coating, acid pickling, drying and warehousing are sequentially performed. The treatment process of the aluminum-clad metal wire for the high-strength shelf back mesh, which is designed by the invention, has the advantages that the overall performance, such as mechanical strength and corrosion resistance, of alloy metal wires and back mesh finished-products can be improved, and the service life of the back mesh is greatly prolonged.

The present invention discloses a AISI4340 prestress steel bar manufacturing method, wherein a AISI4340MOD steel is adopted as a billet material, the billet material is subjected to smelting and finish rolling to obtain a prestress steel bar forging stock with the required size, the prestress steel bar forging stock is sequentially subjected to a hydrogen diffusion heat treatment, rough processing, water cooling quenching and air cooling quenching, a polyethylene corrosion resistance coating is coated on the outer surface of the steel bar forging stock, and a polyethylene heat shrink sleeve is arranged outside the polyethylene corrosion resistance coating. According to the AISI4340 prestress steel bar manufacturing method designed by the present invention, the obtained AISI4340 prestress steel bar has characteristics of high strength, good ductility, strong delayed fracture resistance, steel saving, low relaxation, easy welding, good upsetting property and the like, and further has effects of substantially enhanced corrosion resistance sealing property, and effectively improved mechanical strength.

The present invention discloses 600 MPa-grade-and-above high strength steel bars and a reinforced concrete application method thereof. According to the present invention, 0.4-0.65% by weight of Mn, 0.6-0.7% by weight of Cr, 0.15-0.3% by weight of Mo, 0.5-0.65% by weight of Ni, and 0.25-0.4% by weight of V are added to the steel bar component so as to improve strength, toughness, corrosion resistance, wear resistance and impact resistance of the steel bar, make the steel bar be compact, improve hardenability of the steel, and improve atom activities of the elements such as C and N, such that deformation and cracking can be reduced; and the application method of the diameter 6 mm and diameter 22 mm 600 MPa-grade-and-above high strength steel bars in the reinforced concrete has advantages of steel bar consumption reduction, carrying capacity increase, and crack extension resistance.

The invention discloses a preparation process of an aluminum iron alloy wire. The aluminum iron alloy wire is prepared by wrapping the outer surface of an alloy wire with aluminum, and the preparation process is prepared from the following chemical components in percentage by weight: 40-60% of aluminum, 35-55% of ferrum, 0.15-0.2% of carbon, 0.15-0.2% of silicon, 0.02-0.03% of phosphorus, 0.03-0.04% of sulfur, 0.04-0.05% of copper, 3.0-5.0% of cerium, less than or equal to 1.8PPm of hydrogen, less than or equal to 75PPm of nitrogen, less than or equal to 18PPm of oxygen and the balance being impurities. By using the preparation process of the aluminum iron alloy wire, designed by the invention, the quality can be greatly improved, the whole process is simple and easy to implement, and the yield of the aluminum is increased.

The invention discloses a 600MPa grade-and-more high-strength building steel bar and a duct piece application method thereof. The high-strength steel bar comprises 0.32-0.7wt% of C, 0.5-1.2wt% of Ni, 0.3-2.1wt% of Cr, 0.6-1.3wt% of Si, 0.4-0.8wt% of Mn, 0.6-0.7wt% of Cr, 0.12-0.28wt% of Mo, 0.3-0.55wt% of Ni, 0.2-0.3wt% of V, below 0.05wt% of S, below 0.02wt% of P, and the balance Fe. A production method of the high-strength steel bar comprises the following steps: 1, sending a steel bar into a heating furnace, and heating; 2, carrying out preliminary hot rolling of the steel bar; 3, putting the above obtained cooled steel bar in a tempering heating furnace, and heating to 500-550DEG C; 4, carrying out high pressure injection of the obtained heat-insulated steel bar with water or a quenching liquid; and 5, carrying out examination warehousing. The high-strength steel bar has the advantages of strong bearing capacity, security improvement, reduction of the consumption of the steel bar, and cost reduction.

The invention discloses a super double-phase stainless steel tube and a production process thereof. The super double-phase stainless steel tube comprises the following components in percentage by weight: 7.6%-7.8% of Ni, 4.2%-4.5% of Mo, 22.1%-22.3% of Cr, 0.015%-0.018% of C, 0.045%-0.05% of Si, 0.3%-0.5% of Mn, more than 0 and not more than 0.02% of S, more than 0 and not more than 0.035% of P, 0.03%-0.05% of Cu, 0.012%-0.016% of Co, 0.03%-0.05% of O, 0.3%-0.5% of Al, 0.07%-0.09% of Nb, 0.001%-0.003% of B, 0.03%-0.05% of N and the balance being Fe. The production process can be used for sufficiently dissolving and uniformly dispersing carbide by virtue of two heating steps and two cooling steps, so that inter-crystalline corrosion and point corrosion caused by precipitation of the carbide among the crystals are avoided; moreover, the super double-phase stainless steel tube has good strong plasticity.