Patent classifications
B22D11/0622
WEATHERING STEEL
A method of making weathering steel by preparing a molten melt producing an as-cast carbon alloy steel strip with a corrosion index of at least 6.0 comprising, by weight, 0.02%-0.08% carbon, <0.6% silicon, 0.2%-2.0% manganese, <0.03% phosphorus, <0.01% sulfur, <0.01% nitrogen, 0.2%-0.5% copper, 0.01%-0.2% niobium, 0.01%-0.2% vanadium, 0.1%-0.4% chromium, 0.08%-0.25% nickel, <0.01% aluminum, and the remainder iron and impurities. The molten melt is solidified and cooled into a cast strip ≧4 mm in thickness in a non-oxidizing atmosphere. The strip is hot rolled in an austenitic temperature range above Ar.sub.3 to between 10% and 50% reduction, cooled at above 20° C./s and coiled below 700° C. to form a steel strip with a microstructure comprising bainite and acicular ferrite with more than 70% niobium in solid solution. Then, age hardening the strip resulting in a yield strength of at least 550 MPa and a total elongation of at least 8%.
High formability steel sheet for the manufacture of lightweight structural parts and manufacturing process
A steel sheet has a composition comprising, by weight: 0.010%≤C≤0.080%, 0.06%≤Mn≤3%, Si≤1.5%, 0.005%≤Al≤1.5%, S≤0.030%, P≤0.040%, Ti and B such that: 3.2%≤Ti≤7.5% and (0.45×Ti)−1.35≤B≤(0.45×Ti)−0.43, optionally Ni≤1%, Mo≤1%, Cr≤3%, Nb≤0.1%, V≤0.1%, the remainder being iron and unavoidable impurities resulting from the smelting. The steel sheet has a structure consisting of ferrite, at most 10% of austenite, and precipitates comprising eutectic precipitates of TiB.sub.2, the volume fraction of TiB.sub.2 precipitates with respect to the whole structure being of at least 9%, the proportion of TiB.sub.2 precipitates having a surface area lower than 8 μm.sup.2 being of at least 96%.
FEEDSTOCK FOR METAL FOIL PRODUCT AND METHOD OF MAKING THEREOF
The present invention discloses a product comprising a 1xxx, 3xxx and 8xxx series aluminum alloy made by a non-ingot casting process, where the aluminum alloy has a thickness of about 5 micrometers to about 150 micrometers for a foil product. The product has an O-temper tensile strength, O-temper elongation, and O-temper Mullen pressure that are at least 10% greater compared to the average values of the same alloy in O-temper cast using a slab or roll-casting process. The product is substantially free of pinholes caused by centerline segregation of intermetallic particles. In another embodiment, the present invention discloses a 8111 or 8921 aluminum alloy made by a non-ingot casting process, where the aluminum alloy has a thickness of about 5 micrometers to about 150 micrometers for a foil product. The product has an O-temper tensile strength, O-temper elongation, and O-temper Mullen pressure that are at least 10% greater than the average values of the same alloy in O-temper made from feedstock prepared by slab or roll casting processes. The product is substantially free of pinholes caused by centerline segregation of intermetallic particles.
Martensitic stainless steel highly resistant to corrosion, and method for manufacturing same
Provided is a martensitic stainless steel having excellent productivity and high corrosion resistance, which comprises, as percentages by weight, 0.45 to 0.60% carbon, 0.02 to 0.08% nitrogen, 0.2 to 0.4% silicon, 0.3 to 0.6% manganese, 12 to 15% chromium, one or more kinds of 0.1 to 1.5% molybdenum or 0.1 to 1.5% tungsten and Fe and other unavoidable impurities as remnants.
Aluminum fin alloy and method of making the same
The present invention relates to an aluminum alloy product for use as a finstock material within brazed heat exchangers and, more particularly, to a finstock material having high strength and conductivity after brazing. The invention is an aluminum alloy finstock comprising the following composition in weight %: TABLE-US-00001 Fe 0.8-1.25; Si 0.8-1.25; Mn 0.70-1.50; Cu 0.05-0.50; Zn up to 2.5; other elements less than or equal to 0.05 each and less than or equal to 0.15 in total; and balance aluminum.
The invention also relates to a method of making the finstock material.
Steel plate for producing light structures and method for producing said plate
The invention relates to a steel plate, the chemical composition of which comprises, the contents being expressed by weight: 0.010%≦C≦0.20%, 0.06%≦Mn≦3%, Si≦1.5%, 0.005%≦Al≦1.5%, S≦0.030%, P≦0.040%, 2.5%≦Ti≦7.2%, (0.45×Ti)−0.35%≦B≦(0.45×Ti)+0.70%, and optionally one or more elements chosen from: Ni≦1%, Mo≦1%, Cr≦3%, Nb≦0.1%, V≦0.1%, the balance of the composition consisting of iron and inevitable impurities resulting from the smelting.
Method and device for cleaning a surface of a twin-roller continuous thin strip casting roller
A method for cleaning a surface of a twin-roller continuous thin strip casting roller, each casting roller of a twin-roller continuous thin strip casting machine using two brush rollers arranged at a top and bottom for cleaning the surface, wherein a rotational direction of one brush roller is the same as the casting roller, a linear speed of the casting roller is constant and greater than a rotational speed of the casting roller, and a roller surface cleaning device controls a distance or pressure between the brush rollers and the casting roller by a position control device fixed on a casting roller bearing seat, which controls the flattening amount to be within 1-10 times of an average pit depth of a casting roller face.
METHOD AND CASTING/ROLLING SYSTEM FOR CASTING AND ROLLING A CONTINUOUS STRAND MATERIAL
A method for operating a casting/rolling system and to a corresponding system for casting and rolling an endless strand material. The casting/rolling system comprises a strand casting machine and a rolling train arranged downstream of the strand casting machine. The method has the following step: controlling the drive for the rollers of the first roller frame of the rolling train by means of a drive control in response to a target value specification of the pass sequence model. Furthermore, the drive of the at least one strand guiding roller is controlled by a strand guiding roller drive control in response to a target value specification of the strand casting machine drive model.
Modelling of a cast rolling device
A computer determines a thickness and/or a temperature of a metal strip. The computer determines the temperatures occurring along a respective rotation part of the respective surface elements of the rotary elements and a rotary element shape which forms in the region of a draw-off point on the respective surface element, by a respective rotary element model and using an exchanged enthalpy quantity, the respective contact time with a metal and a respective cycle time exchanged per time unit of a respective rotary element of a casting device with the environment thereof. The temperature of the metal situated in the die region, and the heat flow from the metal to the respective surface element, are determined by a respective metallurgical solidification model and using a metal temperature, the temperatures of the surface elements, the rotary element shape and characteristic metal values.
SLAB CASTING METHOD
A slab casting method using a twin-drum continuous casting device manufactures a slab by solidifying molten metal by a pair of rotating casting drums includes calculating estimated sheet thicknesses on both ends in a width direction of the slab from equation 1 ((estimated sheet thickness)=(cylinder screw down position)+(elastic deformation of casting drum)+(casting drum housing screw down system deformation)+(drum profile of casting drum)−(elastic deformation of casting drum at the time of screw down position zero adjustment)) by using a casting drum housing screw down system deformation characteristic indicating a deformation characteristic of housings that support the casting drums and a deformation characteristic of a screw down system that screws down the casting drums obtained before casting of the slab starts, and controlling screw down positions of cylinders provided on both ends in a width direction of the casting drums.