35results about How to "Grain refinement is obvious" patented technology

The invention discloses an aluminum alloy ingot. The aluminum alloy ingot comprises, by weight , 9.6%-12.0% of Si, 1.5%-3.5% of Cu, less than 0.3% of Mg, less than 1.3% of Fe, less than 1.0% of Zn, less than 0.5% of Mn, less than 0.5% of Ni, less than 0.3% of Sn, 1%.-2%. of Sr, 1%.-2%. of Ti, 1%.-2%. of B and the balance Al. The Si element is added to the aluminum alloy ingot so that strength and toughness of the aluminum alloy ingot are effectively improved, and the Ti and B elements added into the aluminum alloy ingot enables a die-casting product to generate good grain refinement, casting cracks are effectively avoided, the appearance of a casting is improved, the surface quality of the ingot is improved, particularly cold shut of the ingot is reduced, and the impact toughness of the aluminum alloy ingot is effectively improved by 15%-20% on the condition that the strength of the aluminum alloy ingot is not reduced.

The invention belongs to the technical field of coating preparation and particularly relates to an AlCrSiN nano-composite coating resistant to high temperature and abrasion and a preparation method thereof. According to the AlCrSiN nano-composite coating resistant to high temperature and abrasion and the preparation method thereof, a pulsed arc ion plating method is adopted; and a Cr interface implantation layer, a CrN transition layer and an AlCrSiN surface functional layer are sequentially deposited on the surface of a base body from bottom to top. Experimental results show that the AlCrSiNnano-composite coating obtained through the preparation method is excellent in high-temperature stability and abrasion resistance and has the advantages of being small in number of surface large particles, low in internal stress, high in film base bonding strength and the like; and the AlCrSiN nano-composite coating is applicable to surface protection of products such as mechanical parts, tools and molds.

The invention provides a production method for controlling fault detection defect of medium thick plate Q345 steel. The composition design is: 0.15-0.18% of C, 0.25-0.35% of Si, 1.1-1.2% of Mn, equal to or less than 0.018% of P, equal to or less than 0.008% of S, 0.025-0.04% of Al, 0.015-0.02% of Ti, and 0.002-0.004% of Ca; an Al-Ca refining agent is added during LF refining, the Al-Ca reining agent is began to feed into a steel ladle when the temperature reaches 1530 DEG C, and the addition amount is 0.5-1.0kg/t steel; the S content of the pretreated molten iron is 0.001-0.002%, and the tapping temperature of a converter is kept at 1620 DEG C to 1630 DEG C; the Al2O3 content of refined slag of an LF refining furnace is 30-35%, the delivery of current is 10min to 15min, and the final molten steel nitrogen content is 0.002-0.004%; and the molten steel liquid level of a casting pot is controlled to be 500mm to 550mm, and the steel ladle long nozzle is protected by argon seal, thus the nitrogen content of the continuous casting molten steel is enhanced by 0.0003-0.0008%, and the molten steel continuous casting temperature is 1525 DEG C to 1535 DEG C.

Disclosed is a method for preparing dispersion strengthened copper-based composites through equal channel angular pressing (ECAP). The dispersion strengthened copper-based composites after hot extrusion, rolling, drawing or rotary swaging forming are sent to an ECAP die (3) which is preheated to 100-500 DEG C and coated with lubricants after preheating at the temperature of 200-900 DEG C and preserving heat for 0.5-5h; dispersion strengthened copper-based composite sticks, plates, tubes, square materials and the like are pressed and formed under pressing pressure (1) of 100-1000MPa at the pressing speed of 1-100 mm/min; the next pressing process is performed after each pressing process, and altogether 2-10 pressing processes are performed. According to the method, grains of the dispersion strengthened copper-based composites are refined effectively; comprehensive performance such as strength, hardness and electric conductivity of the dispersion strengthened copper-based composites is improved; the method has the advantages that operation is easy, machining efficiency is high, and cost is low. The dispersion strengthened copper-based composites prepared through the method can be widely applied to the aviation field, the aerospace field, the electronic field, the manufacturing field and the like.

The invention discloses an Mg-Nd-Zn-Zr alloy material containing Y. The Mg-Nd-Zn-Zr alloy material is characterized by comprising the following components in parts by mass: 0.2 of Zn, 0.4 of Zr, 2.0 of Nd, 4-8 of Y, and the balance of Mg. A preparation process is characterized in that pure magnesium, pure zinc, 30% of Zr magnesium zirconium intermediate alloy and 31.72% of Y magnesium yttrium intermediate alloy are smelted by using a RJ-2 covering agent at a smelting temperature of 770 DEG C, are stood by 15 minutes after being totally molten, are poured in an iron mold, preheated to 200 DEG C, at 720 DEG C, and are molded by pouring.

The invention relates to an aluminum alloy ingot. The aluminum alloy ingot is prepared from, by weight percent, 7.2%-11.4% of Si, 1.2%-1.5% of Cu, 0.1%-0.3% of Mg, 0.2%-0.4% of Fe, 1.2%-1.4% of Zn, 0.2%-0.4% of Ni, 0.1%-0.3% of Sn, 1.2%-2.4% of Sr, 2.1%-2.4% of Ti, 2.1%-2.4% of B, 1.2%-1.4% of Sb, 0.3%-0.5% of As, 0.22%-0.44% of RE, 0.4%-1.4% of LaCe, 0.3%-0.5% of Pr and the balance Al and inevitable impurities, wherein the content of the impurities is not larger than 0.1%. The aluminum alloy ingot is good in comprehensive performance, resistant to corrosion and stable in performance.

The invention relates to the technical field of alloys, in particular to an alloy material easy to mold at a time. The alloy material is characterized in that the alloy material comprises, by weight, 0.2-0.4% of zirconium, 0.1-0.3% of zinc, 5-7% of silicon, 0.02-0.1% of strontium, 0.05-0.2% of molybdenum, 0.1-0.3% of nickel, 0.08-0.3% of copper, 0.02-0.04% of scandium, 2-15 ppm of beryllium, and the balance aluminum and less than 0.1% of impurities. Castings cannot crack due to uneven cooling in the cooling process, and the cooling speed is 5% higher than that of conventional alloys. Accordingly, castings cast through one-step molding are smooth in surface and high in strength and impact toughness.

The invention discloses an iron-based wear-resistant composite material and a preparation method thereof. The preparation method comprises the following steps: preparing an iron-based wear-resistant composite coating on the surface of an iron-based alloy matrix material by using iron-based composite powder by using a laser cladding method to obtain a composite body; polishing and cleaning the surface of the composite body; then carrying out laser shock, and surface enhancement treatment of the iron-based wear-resistant composite coating is achieved; performing cyclic heat treatment on the composite with the surface subjected to laser shock to eliminate residual stress; and the iron-based composite powder is obtained by uniformly mixing micron La2O3 powder, micron Al2O3 powder and micron FeCrNiSiB powder, carrying out liquid nitrogen circulation subzero treatment and drying, and the iron-based composite powder contains the following components in percentage by mass: 0.05%-10% of the micron La2O3 powder, 0.1%-45% of the micron Al2O3 powder and 50%-95% of the micron FeCrNiSiB powder. According to the iron-based wear-resistant composite material and the preparation method thereof provided by the invention, the composite coating with good performance is prepared on the surface of an iron-based alloy material, the service life of an iron-based alloy matrix is prolonged, and the preparation method has great significance in repairing and reconstruction of engineering machinery.

The invention provides a tantalum-containing copper alloy wire/strip comprising the following components of, by mass, 0.01%-1.0% of tantalum, 0.01%-1.0% of silver, 0.01%-0.5% of iron, and the balancecopper. The invention further provides a preparation method of the tantalum-containing copper alloy wire/strip. A continuous casting machine conducts high-temperature treatment on copper-tantalum intermediate alloy, silver, copper-iron intermediate alloy and copper, drawing casting is conducted after cooling, then repeated drawing is conducted, after micro machining, continuous heat treatment is conducted through annealing equipment, the tantalum-containing copper alloy wire is obtained, and the tantalum-containing copper alloy strip of the needed specifications is obtained through rolling ofa double-roller rolling mill. With adding of the tantalum, magnetoconductivity of the copper alloy is improved effectively, the strength of the copper alloy is improved through adding of the silver, good electroconductibility of the copper alloy wire/strip is ensured, magnetoconductivity of the copper alloy can be further enhanced through the iron element in the copper alloy, and the copper alloymaterial has good magnetoconductivity, electroconductibility and strength through the element combination of tantalum, silver, iron and copper.

The invention discloses a method for preparing an aluminum-scandium alloy with high scandium content. The method comprises the steps that metal scandium and metal aluminum are weighed according to thescandium content in the aluminum-scandium alloy needing to be prepared; the obtained materials are added into a medium-frequency induction melting furnace, continuously vacuumizing is carried out, and then heating is carried out to 1200-1600 DEG C to melt the metal scandium and the metal aluminum; after complete melting is achieved, alloy liquid is obtained, and heat preservation is carried out for 20-40 min; and high-purity argon is introduced in, the alloy liquid subjected to heat preservation is poured into a water-cooled copper die, circulating water is cooled to 1-15 DEG C by adopting amold circulating water refrigerating system, the cooled circulating water is introduced into the water-cooled copper die to circularly cool the alloy liquid, and cooling and solidifying of the alloy liquid can be completed within 3-8 seconds to obtain an aluminum-scandium alloy cast ingot with scandium content of 5%-99%. According to the method, rapid cooling can be achieved within 3-8 s, the aluminum-scandium alloy with high scandium content which is high in purity, high in compactness, low in segregation, uniform in component and low in cost can be prepared, and the requirement of the current market for the aluminum-scandium alloy with high scandium content is met.

The invention discloses a method for additive manufacturing of H13 steel, and relates to the technical field of additive manufacturing die steel rear end heat treatment. The method comprises the following steps: S1, material selection: selecting 15-53 [mu] m H13 steel powder; S2, drying: drying the H13 steel powder in a protective atmosphere; S3, printing: printing the H13 steel on CAD modeling software; S4, performing solution treatment: performing solution treatment on a H13 steel profile formed through additive manufacturing; S5, performing aging heat treatment: performing double aging heat treatment on the H13 steel profile subjected to solid solution treatment and then air cooling to the room temperature. Compared with casting-state H13 steel, the printing-state H13 steel subjected to the heat treatment process has the advantages that the internal microstructure defects are fewer, pores are greatly reduced, grain refinement is obvious, and the microstructure is uniform.

The invention discloses a preparation method of an aluminum-copper alloy material. The aluminum-copper alloy material comprises the following components in percentages by weight: 1-4% of copper, 2-5% of titanium, 0.1-1.5% of iron, 0.2-1.5% of silicon, less than 1% of rare earth and the balance of aluminum; and the rare earth element is at least one of lanthanum, cerium, neodymium and yttrium. The preparation method comprises the following steps: (1) casting, and (2) heat treatment. The aluminum-copper alloy material has high strength, excellent plasticity and good mobility; and after casting of the aluminum-copper alloy material, defects such as sand holes, pores and shrinkage cannot be caused easily.