7results about How to "Eliminate segregation" patented technology

The application belongs to the technical field of nodular cast iron, and particularly relates to a novel nodular cast iron and a preparation method and application thereof. The novel nodular cast iron has the following element composition and mass percentage: C 3.75-3.90%, Si 2.00-2.20%, Mn≤0.10%, Mg 0.035-0.055%, RE≤0.008%, P≤0.02%, S≤0.01%, Cu 0.1-2.0%, Mo≤0.02%, Ni 1.0-2.0%, Sn≤0.05%, Ti≤0.01%, V≤0.02%, B≤0.0008%, Sb 0.003-0.007%, Cr≤0.05% and the balance of Fe; and is composed of 45-55% pearlite and 45-55% ferrite. By controlling the element content in the nodular cast iron and combining with an efficient preparation method, the nodular cast iron with a pearlite content of 45-55% and a spheroidization rate of greater than 95% is obtained, and the nodular cast iron exhibits high strength, high plasticity and a relatively high low-temperature impact value.

This invention discloses a magnesium-lithium alloy cabin structure component and its forming method, belonging to the field of magnesium-lithium alloy forming technology. The method includes the following steps: S1. Pre-treatment of the magnesium-lithium alloy ingot, followed by free forging or extrusion to obtain a billet; S2. Die forging the billet and air-cooling it to room temperature to obtain a forging; S3. Holding the forging at 270~290℃ for 4~6 hours, then quenching it in cold water and performing T5 heat treatment; finally, aging strengthening by holding it at 180~220℃ for 8~12 hours. The forming method of this invention improves product uniformity through pre-treatment and enhances product strength and toughness through heat treatment. This forming method has broad application prospects and is expected to be industrialized.

This invention relates to the field of hot extrusion manufacturing technology, specifically to a high-strength weldable 6xxx series aluminum alloy profile, its manufacturing method, and its application. The aluminum alloy profile is composed of the following weight percentages: Si: 0.80%~1.2%, Fe≤0.20%, Cu: 0.40%~0.80%, Mn: 0.30%~0.70%, Mg: 0.70%~1.1%, Cr≤0.25%, Zn≤0.10%, Ti≤0.10%, Zr: 0.05%-0.20%, Pb<0.01%, with the balance being Al and unavoidable impurities. The profile meets the following performance requirements: tensile properties, R... m ≥420MPa, R p0.2 ≥330MPa, A 50mm ≥8.0%; Fatigue performance: at r=0.1, N=1×10 7 Under the same conditions, the fatigue strength σ of the smooth sample is ≥145MPa, realizing the lightweight manufacturing of high-speed trains.

The application discloses a GH625 forging bar and a preparation method thereof, and belongs to the technical field of metallurgy. The preparation method of the GH625 forging bar comprises the following steps: subjecting a consumable ingot to homogenization treatment; and subjecting the consumable ingot subjected to the homogenization treatment to forging. The homogenization treatment comprises the following steps: 1100 DEG C.-1150 DEG C. heat preservation for 10h-30h and 1150 DEG C.-1220 DEG C. heat preservation for 10h-80h. The preparation method of the GH625 forging bar can efficiently reduce segregation and shrinkage holes formed in the preparation process of the super-large-size GH625 forging bar by combining the homogenization treatment and the forging deformation process, and improves the product yield and the qualified rate.

The application discloses a preparation method of GH4141 alloy small-size rod, which comprises the following steps: step 1, a multi-stage step high-temperature homogenization heat treatment is carried out on a GH4141 ingot, and then 8-12 times of open-die forging is carried out to obtain a Φ120mm-Φ180mm rod; step 2, the Φ120mm-Φ180mm rod after the open-die forging is rolled to a Φ50mm-Φ70mm rod in the middle of one time of rolling; step 3, after the surface of the Φ50mm-Φ70mm intermediate-rolled rod blank is cleaned, one or two times of rolling is carried out to obtain a Φ8mm-Φ32mm rod, and then solid solution heat treatment, aging heat treatment, straightening and grinding are carried out to obtain a Φ7mm-Φ30mm finished rod. The carbide distribution of the GH4141 alloy rod processed by the method is uniform, the solid solution structure is uniform and consistent without mixed crystals, and the rod performance meets the corresponding standard requirements.

This invention discloses a continuous casting and rolling process for high-strength copper alloys, relating to the field of metallurgical engineering technology, comprising the following steps: (a) heating the copper matrix containing tin, zinc, and nickel, and adding appropriate amounts of rare earth elements, in a melting furnace to 1200-1300°C until a uniform copper alloy melt is formed; (b) maintaining the copper alloy melt in an optimal casting temperature range of 1150-1200°C using a holding furnace with temperature control function; (c) continuously casting the held copper alloy melt into long strip billets using a continuous casting machine equipped with an electromagnetic stirring device. The technical solution provided by this invention ensures the fluidity and purity of the copper alloy melt, significantly reduces inclusions using electromagnetic stirring technology, effectively promotes uniform solid solution of alloying elements and the formation of fine, dispersed strengthening phases, introduces a homogenization treatment stage, eliminates component segregation, and improves the uniformity of the material.

This invention provides a method for preparing a nickel-based superalloy, relating to the field of superalloy material preparation and heat treatment technology, comprising the following steps: sequentially subjecting a nickel-based superalloy ingot to electroslag remelting, homogenization, and forging to obtain the nickel-based superalloy. In this invention, the electroslag remelting process simultaneously precipitates primary M6C carbides and primary SiC carbides. Compared to M6C, SiC is easier to precipitate and dissolve; therefore, after the primary SiC carbides consume some carbon, less primary M6C carbides are formed, thus reducing the difficulty of carbide dissolution. The homogenization process then allows the primary carbides to fully dissolve into the austenitic matrix and eliminates elemental segregation. Finally, the forging process ensures that the secondary M6C carbides reprecipitate from the matrix in a dispersed distribution, preventing the primary carbides from agglomerating in bands along the forging direction due to genetic effects, thereby avoiding damage to the alloy's strength and plasticity.