摘要:
A method for manufacturing a steel product, comprising the steps of: providing a heated steel starting product at a temperature comprised between 380°C and 700°C, having a metastable fully austenitic structure, with a composition comprising, in percent by weight: 0.15% ≤ C ≤ 0.40%,1.5% ≤ Mn ≤ 4.0%, 0.5% ≤ Si ≤ 2.5%, 0.005% ≤ Al ≤ 1.5%, with 0.8% ≤ Si+Al ≤ 2.5%, S ≤ 0.05%, P ≤ 0.1%, at least one element chosen among Cr and Mo, such that: 0% ≤ Cr ≤ 4.0%, 0% ≤ Mo ≤ 0.5%, and 2.7% ≤ Mn + Cr + 3 Mo ≤ 5.7%, and optionally one or several elements chosen among: Nb ≤ 0.1%, Ti ≤ 0.1%, Ni ≤ 3.0%, 0.0005% ≤ B ≤ 0.005%, 0.0005% ≤ Ca ≤ 0.005%, the balance of the composition consisting of iron and unavoidable impurities resulting from the smelting; subjecting said starting product to a hot forming step at a temperature comprised between 700°C and 380°C, with a cumulated strain e b between 0.1 and 0.7, in at least one location of said heated steel starting product, to obtain a fully austenitic hot-formed steel product; then quenching the hot-formed steel product by cooling it down, at a cooling rate VR 2 superior to the critical martensitic cooling rate, to a quenching temperature QT lower than Ms in order to obtain a structure containing between 40% and 90% of martensite, the rest of the structure being austenite; then maintaining at, or reheating the product up to a holding temperature PT between QT and 470°C and holding it at said temperature PT for a duration Pt between 5s and 600s.
摘要:
The present invention provides methods and systems for applying a coating to a non-ferrous or ferrous material that includes providing a material, a heat source, an immersion tank, and a drying environment. The material is placed within the heat source and heated to a temperature between the range of between about 204.44°C to about 537.78°C (400°F to about 1000°F). The material is immersed within an immersion containing a ratio of molybdenum disulfide solution to water of between about 2:1 to about 4:1 at a temperature between about 26.67°C to about 48.89°C (about 80°F to 120°F), and the material is dried at a temperature between about 51.67°C to about 98.89°C (125°F and 210°F).
摘要:
A process for rejuvenating a turbine disk having a plurality of slots includes the steps of determining a depth of a damaged layer containing M23C6 carbide dissolution; and removing the damaged layer from the slots in accordance with the determined depth.
摘要:
A method of forming a coating of an Al-Zn-Si-Mg alloy on a steel strip to form an Al-Zn-Mg-Si coated steel strip is disclosed. The method includes the steps of dipping steel strip into a bath of molten Al-Zn-Si-Mg alloy and forming a coating of the alloy on exposed surfaces of the steel strip and cooling the coated strip with cooling water. The cooling step includes controlling the pH of cooling water to be in a range of p H 5-9. Particular embodiments focus on Al-Zn-Si-Mg alloys that contain the following elements in % by weight: Zn: 30 to 60, Si: 0.3 to 3, Mg: 0.3 to 10, and Balance Al and unavoidable impurities.
摘要翻译:公开了一种在钢带上形成Al-Zn-Si-Mg合金涂层以形成Al-Zn-Mg-Si涂层钢带的方法。 该方法包括将钢带浸入熔融的Al-Zn-Si-Mg合金浴中并在钢带的暴露表面上形成合金涂层并用冷却水冷却涂覆的条带的步骤。 冷却步骤包括将冷却水的pH控制在p H 5-9的范围内。 具体实施方案关注含有以重量%计的以下元素的Al-Zn-Si-Mg合金:Zn:30至60,Si:0.3至3,Mg:0.3至10,余量为Al和不可避免的杂质。
摘要:
The present invention relates to a metal wire having a dual structure, comprising a surface layer comprising silver (Ag), and a central metal layer inside the surface layer, and a preparation method thereof. According to the present invention, an ultrafine silver wire having a high strength is prepared at low cost with high efficiency while maintaining the antibacterial property of silver, thereby being very advantageous for mass production of an antibacterial fiber product.
摘要:
Disclosed herein is a method to apply waterborne primer, basecoat and clearcoat compositions in a wet-on-wet manner followed by the curing of all three applied compositions to form a durable protective coating on a substrate. The primer composition comprises (meth)acrylic latex, polyurethane resin, melamine and, optionally, polyesters.
摘要:
An exemplary method of making a first component for contacting another component includes applying a wear and corrosion resistant material layer onto a surface of the first component. The wear and corrosion resistant material layer is then roughened subsequent to having been applied to the surface. A component comprises an exemplary elevator sheave that includes a metallic body having a sheave surface that is adapted to contact an elevator tension member. A corrosion resistant material layer on the sheave surface has a thickness that is greater than about 5 microns.
摘要:
The invention relates to the technology of applying coatings to the surfaces of articles, and in particular, to gas-dynamic methods of applying coatings with the use of an inorganic powder, and it can be used in different branches of mechanical engineering. A compressed gas is delivered to the heater (1) to be heated to the required temperature that keeps the particles from sticking to the nozzle walls. The heated gas enters the supersonic nozzle (2) wherein it sequentially passes through a converging portion, the throat (3) and a diverging portion of the nozzle and acpelerates up to supersonic velocity. The powders to be sprayed are introduced into said supersonic gas flow through powder injection components (5). The powder particles are accelerated by a high-velocity gas flow in the acceleration portion (7) of the nozzle and then they are directed to the substrate surface. The gist of the invention is the disclosure of the parameters of a nozzle portion, positioned downstream of the powder injection point and intended for the acceleration of the powder, providing the increase of sprayed powder deposition efficiency and the retention of the possibility to use an elevated temperature of the compressed gas and to use the powders having hard particles.
摘要:
Die Erfindung betrifft ein beschichtetes Stahlblech oder -band mit einer aus Stahl bestehenden Grundschicht, auf deren mindestens eine Oberseite durch Schmelztauchbeschichten ein Überzug aufgetragen ist, der aus einer aus 0,05 - 0,30 Gew.-% Al und 0,2 - 2,0 Gew.-% Mg, Rest Zink und unvermeidbare Verunreinigungen bestehenden Schmelze gebildet ist und bei einer Überzugsdicke von höchstens 3,5 μm und einem Auflagengewicht von höchstens 25 g/m 2 je Seite gewährleistet, dass das Stahlblech im nach DIN 50021-SS durchgeführten Salzsprühnebeltest frühestens nach 250 Stunden eine erste Rotrostbildung zeigt. Mit einem solchen Blech oder -band steht ein Stahlflachprodukt zur Verfügung, das eine optimale Kombination von hoher Korrosionsbeständigkeit und optimierter Schweißbarkeit besitzt und welches sich insbesondere für die Verwendung als Werkstoff für den Automobilkarosseriebau oder für den Bau von Hausgeräten eignet.