31results about How to "Raise the initial melting temperature" patented technology

The invention relates to high-temperature alloy technology, and in particular provides an isometrical cast nickel-base high-temperature alloy with low density, high incipient melting temperature and good casting property and a preparation process thereof, which can be used for floating tile materials of a combustion chamber. The alloy comprises the following compositions by mass percentage: 0.03 to 0.06 percent of C, 5 to 12 percent of Cr, 5.5 to 6.5 percent of Al, 3 to 8 percent of Co, 3 to 7 percent of W, 2 to 4 percent of Mo, 1.6 to 3.2 percent of Nb, 0.01 to 0.03 percent of B, 0.008 to 0.025 percent of Y and the balance of Ni. A vacuum induction furnace is adopted to smelt a master alloy, and a smelting crucible is a CaO crucible or a MgO crucible; and the operation process comprises the following steps: putting alloying elements such as carbon, chromium, cobalt, tungsten, molybdenum and niobium in proportion and a nickel plate into the crucible; melting the alloy when the vacuum degree reaches between 50 and 0.1 Pa; and after completion of the melting, refining for 30 to 300 seconds at a temperature of between 1,550 and 1,600 DEG C, cutting off electricity, forming a film, breaking the film to add Al and Al-Y and Ni-B interalloy for uniform stirring, and casting a master alloy pig at a temperature of between 1,450 and 1,500 DEG C. The invention solves the problems of low incipient melting temperature, poor plasticity and inoxidability and the like of the nickel-base high-temperature alloy.

The invention discloses an abrasion-proof and corrosion-resistant nickel-based alloy wire and a preparation method thereof. The alloy wire comprises the following components: 17-21% of C, 20-25% of Co, 1.8-2.2% of W, 6.4-9.5% of Mo, 1.4-1.8% of Al, 3.2-4.5% of Ti, 0.1-0.5% of Nb, 0.1-0.5% of Hf, 1.2-1.8% of Ta, 0.03-0.06% of Re, 0.01-0.05% of Ce, 0.02-0.1% of C, 0.005-0.015% of B, 0.02-0.07% of Zr, 0.005-0.008% of Mg, and the balance Ni. The preparation technology of the alloy comprises the steps of vacuum smelting, remelting, forging, hot rolling, drawing, solid solution treatment and aging treatment, namely, raw materials are prepared and smelted based on mass percent and then smelted; the smelted materials are forged and rolled into obtain alloyed wire rods; the alloyed wire rods are drawn at a plurality of times to obtain phi 0.05-0.4mm alloy wires; finally the alloy wires are subjected to solid solution treatment and aging treatment. The abrasion-proof and corrosion-resistant nickel-based alloy wire can be used as a brush wire material for brush sealing of an aircraft engine, a gas turbine, etc., thus the brush sealing effect can be effectively improved, and the service life can be prolonged.

The invention relates to a method for melting nickel-base high-temperature return material K441 alloy, comprising the following steps: refining the return material and/or waste cast pieces in a vacuum induction furnace, decreasing the temperature of molten alloy and casting the molten alloy into a primary material ingot, analyzing the chemical components of the primary material ingot and adjusting the components of the molten alloy by adopting the nickel, aluminum, tungsten, chromium, molybdenum, zirconium, chromium boron master alloy and/or the carbon as the adjusting element component material; refining the primary material ingot and the nickel, the tungsten, the chromium and/or the molybdenum in the adjusting element component material for the second time and heating to cast the molten alloy after a film forming on the molten alloy or adding the carbon, aluminum, chromium boron master alloy and/or the zirconium to the molten alloy to alloy and heating to cast the molten alloy into an alloy ingot after a film forming on the molten alloy. The qualification rate of the return material K441 alloy produced with the method is equal to the qualification rate of the cast piece produced from the new material, and the initial melting temperature of the return material K441 alloy is higher than the initial melting temperature of the alloy produced from the new material with the original production technology.

The invention discloses a heat treatment process of nickel base single crystal superalloy. A differential thermal analysis method and metallographic test method are used to determine the incipient melting temperature of the alloy at 1280 DEG C; and an optical metalloscope is used for observation of the microstructure of alloy after different solid solution treatments, and the stress rupture properties of the alloy are tested. The results show that optimum heat treatment process of the alloy is as below: 1245 DEG C / 2h, AC+1275 DEG C / 4h, AC+1100 DEG C / 2h, AC+850 DEG C / 24h, AC. The single crystal superalloy treated by the process has excellent durability, and creep rupture life reaching 159.35h under 980 DEG C and 235MPa.

The invention belongs to the field of nickel-based superalloys, in particular to a low-rhenium third-generation nickel-based single crystal alloy and a preparation method thereof. Its composition includes Cr, Co, W, Mo, Re, Ta, Al, Hf and Ni, among which Re: 3.0‑4.5%, and it is characterized in that the value of Ta/(W+Mo) is controlled between 1:1‑2 . The main steps of the invention are to use a vacuum consumable furnace to prepare the raw material into a consumable electrode, and to prepare a master alloy through multiple tests; then use the spiral crystal selection method to prepare a single crystal test rod through a directional solidification furnace, and finally test the single crystal at high temperature Alloy test bars were heat treated. The alloy of the present invention mainly improves the durable strength and hot corrosion resistance of the alloy by adjusting the ratio of Ta/(W+Mo), so that the alloy meets the performance of the third-generation nickel-based single crystal superalloy, and contains less Re, and can be used at 900 ° C There is no TCP phase precipitation during long-term aging, and the stability is good.

The invention relates to a directionally solidified nickel-based superalloy and a heat treatment process thereof. In particular, it provides a guide vane material with low density, low cost, high initial melting temperature, good oxidation corrosion resistance and thermal fatigue performance. And a heat treatment process to improve the alloy's tensile properties, durability and thermal fatigue properties. Alloy composition (percentage by weight) of the present invention: B 0.003~0.03, C 0.02~0.2, Cr 8.0~10.0, Al 4.5~6.5, Co 4.0~12.0, Nb 1.8~2.5, W 2.5~4.5, Mo 2.5~4.5, Y 0.005~0.05, more than Ni. The heat treatment process of the present invention: (1) at a temperature of 1210°C to 1240°C, heat preservation for 3h to 5h, and air-cool to room temperature; (2) at a temperature of 1040°C to 1080°C, heat preservation for 3h to 5h, and air cooling to room temperature; ( 3) At a temperature of 850°C to 900°C, keep warm for 16h to 32h, and air cool to room temperature. The alloy of the invention has the characteristics of low density, low cost, high initial melting temperature, good oxidation corrosion resistance and thermal fatigue performance, and is suitable for directional nickel-based guide vane materials.

The invention discloses a magnesium alloy profile material for an automobile oil tank. The magnesium alloy profile material comprises the following components of, by mass, 8%-15% of Al, 2%-4% of Mn, 10%-13% of Zn, 1%-3% of Ni, 7%-9% of Ca, 1%-3% of Cu, 1%-3% of Sc, 0.2%-0.3% of P, 1%-3% of Zr, 2%-4% of B, 0.1%-0.4% of V, 0.002%-0.004% of Nb, 2%-5% of So, 0.01%-0.03% of C, 2%-4% of Co, 0.2%-0.5% of Fe, 0.5%-0.8% of rare earth elements, and the balance Mg. The invention further relates to a preparation method for the magnesium alloy profile material for the automobile oil tank. The preparation method is simple and easy to operate, the prepared oil tank has good corrosion resistance, the service life is long, and the cost is low.

The invention discloses a heat treatment process of a nickel-based single crystal superalloy. A differential thermal analysis method and a metallographic test method are adopted for determining an incipient melting temperature of the alloy to be about 1280 DEG C; an optical metalloscope is used for observation of a microstructure of an alloy after different solid solution treatments, and the endurance properties of the alloy are tested. Results show that an optimum heat treatment process of the alloy comprises 1245 DEG C/2h, AC+1275 DEG C/4h, AC+1100 DEG C/2h, AC+850 DEG C/24h, and AC. The single crystal superalloy treated by the process has excellent endurance properties, and the endurance life reaches 159.35 h under the conditions of the temperature of 980 DEG C and the pressure of 235 MPa.

The invention relates to low-cost high-toughness wrought magnesium alloy capable of being extruded at high speed and a preparation method thereof. The alloy is Mg-Bi-Sn-Al-Ca magnesium alloy and comprises, by mass, 2-45 of Bi, 2-4% of Sn, 1-3% of Al, 0.05-0.5% of Ca and the balance magnesium, wherein the mass ratio of Bi to Sn in the alloy is (0.8-1.2):1. The alloy can be used for high-speed extrusion production at the extrusion speed up to 25 m/min, the production efficiency is improved, and meanwhile, the production cost is reduced. Crystalline grains of a finally extruded product are uniform and fine, a large number of second phases are dispersed in a matrix, the comprehensive mechanical property is good, and the alloy is relatively good in flame retardancy.

The invention discloses a material for magnesium alloy doors and windows. The material for the magnesium alloy doors and windows is composed of Mg, Al, Mn, Zn, Cu, Ni, Sc, P, Zr, Y, Ca, Sr, B, Co and a rare earth element, wherein the rare earth element is composed of Ce, Nd, Gd, Pr, Dy, Yb, La and Sm; the invention further discloses a production method of the material for the magnesium alloy doors and windows, and the method comprises the following steps: smelting, heat treatment, forging, quenching and tempering heat treatment, cooling, checking and storing, the production method is simple and easy, the manufacturing cost is low, and the produced material for the magnesium alloy doors and windows is excellent in corrosion resistance, can resist high temperature, is solderable, and has a prolonged service life.

The invention discloses a heat treatment method for enhancing deforming stability of a polycrystal Ni3Al based high temperature alloy. The method comprises following steps that the alloy is subject tosolid melt treatment at the temperatures of 1100 to 1150 DEG C, 1170 to 1230 DEG C and 1270 to 1300 DEG C, intermediate temperature aging treatment is carried out at the temperature of 1000 DEG C to1100 DEG C, the step is repeated for six to ten times, and finally, the Ni3Al based high temperature alloy with deformation stability enhanced is obtained. After three-segment solid solution treatmentand a series of steps of medium temperature circular aging, the incipient melting temperature of the obtained alloy is improved to about 1370 DEG C from the 1345 DEG C under the as-cast condition, anenhanced type gamma' phase with the small size and the round shape can be evenly separated out from the eutectic area and coexistence region interfaces, and deforming stability of the Ni3Al based alloy under the high temperature condition can be improved.

A treatment process for casting precipitation strengthened nickel-based superalloy comprises the following steps that firstly, mother alloy of the casting precipitation strengthened nickel-based superalloy is put into a vacuum induction furnace to be smelted and then drawn into an alloy bar; secondly, the temperature of the alloy bar in the first step is increased to 1205-1215 DEG C from the room temperature, heat preservation is conducted for 6-8 h, then the temperature is increased to 1220-1230 DEG C, heat preservation is conducted for 10-20 h, and then the alloy bar is cooled to the room temperature through air; thirdly, the alloy bar subjected to solid solution heat treatment in the second step is subjected to stabilizing heat treatment; and fourthly, the alloy bar subjected to heat treatment in the third step is subjected to aging heat treatment. After the alloy is treated by the process, dendritic segregation and eutectic structures are eliminated, the microstructure uniformity is remarkably improved, and the mechanical property of the alloy is greatly improved.