CN113913634A - Method for preparing high-strength Sc-containing cast magnesium-gadolinium alloy - Google Patents
Method for preparing high-strength Sc-containing cast magnesium-gadolinium alloy Download PDFInfo
- Publication number
- CN113913634A CN113913634A CN202111046790.3A CN202111046790A CN113913634A CN 113913634 A CN113913634 A CN 113913634A CN 202111046790 A CN202111046790 A CN 202111046790A CN 113913634 A CN113913634 A CN 113913634A
- Authority
- CN
- China
- Prior art keywords
- magnesium
- alloy
- gadolinium
- strength
- placing
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- DFIYZNMDLLCTMX-UHFFFAOYSA-N gadolinium magnesium Chemical compound [Mg].[Gd] DFIYZNMDLLCTMX-UHFFFAOYSA-N 0.000 title claims abstract description 67
- 229910000748 Gd alloy Inorganic materials 0.000 title claims abstract description 55
- 238000000034 method Methods 0.000 title claims abstract description 16
- 229910045601 alloy Inorganic materials 0.000 claims abstract description 59
- 239000000956 alloy Substances 0.000 claims abstract description 59
- 229910052706 scandium Inorganic materials 0.000 claims abstract description 11
- 239000011159 matrix material Substances 0.000 claims abstract description 8
- 229910052726 zirconium Inorganic materials 0.000 claims abstract description 7
- 238000002360 preparation method Methods 0.000 claims abstract description 5
- 238000000265 homogenisation Methods 0.000 claims abstract description 4
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 claims description 30
- 239000011777 magnesium Substances 0.000 claims description 30
- 238000010438 heat treatment Methods 0.000 claims description 26
- 238000003723 Smelting Methods 0.000 claims description 25
- 229910052749 magnesium Inorganic materials 0.000 claims description 23
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 claims description 22
- 238000004140 cleaning Methods 0.000 claims description 18
- 238000001035 drying Methods 0.000 claims description 18
- 239000002994 raw material Substances 0.000 claims description 18
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims description 16
- 229910052786 argon Inorganic materials 0.000 claims description 15
- 239000011248 coating agent Substances 0.000 claims description 15
- 238000002844 melting Methods 0.000 claims description 15
- 230000008018 melting Effects 0.000 claims description 15
- 238000010791 quenching Methods 0.000 claims description 15
- 230000000171 quenching effect Effects 0.000 claims description 15
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 15
- 229910052688 Gadolinium Inorganic materials 0.000 claims description 14
- 230000032683 aging Effects 0.000 claims description 13
- PEFIIJCLFMFTEP-UHFFFAOYSA-N [Nd].[Mg] Chemical compound [Nd].[Mg] PEFIIJCLFMFTEP-UHFFFAOYSA-N 0.000 claims description 12
- 238000005266 casting Methods 0.000 claims description 12
- 230000005496 eutectics Effects 0.000 claims description 12
- UIWYJDYFSGRHKR-UHFFFAOYSA-N gadolinium atom Chemical compound [Gd] UIWYJDYFSGRHKR-UHFFFAOYSA-N 0.000 claims description 12
- BBYGMOCGCCTLIV-UHFFFAOYSA-N [Sc].[Mg] Chemical compound [Sc].[Mg] BBYGMOCGCCTLIV-UHFFFAOYSA-N 0.000 claims description 10
- QRNPTSGPQSOPQK-UHFFFAOYSA-N magnesium zirconium Chemical compound [Mg].[Zr] QRNPTSGPQSOPQK-UHFFFAOYSA-N 0.000 claims description 10
- 229910000831 Steel Inorganic materials 0.000 claims description 9
- 238000007664 blowing Methods 0.000 claims description 9
- 239000008367 deionised water Substances 0.000 claims description 9
- 229910021641 deionized water Inorganic materials 0.000 claims description 9
- CPLXHLVBOLITMK-UHFFFAOYSA-N magnesium oxide Inorganic materials [Mg]=O CPLXHLVBOLITMK-UHFFFAOYSA-N 0.000 claims description 9
- 235000019353 potassium silicate Nutrition 0.000 claims description 9
- 238000004321 preservation Methods 0.000 claims description 9
- SIXSYDAISGFNSX-UHFFFAOYSA-N scandium atom Chemical compound [Sc] SIXSYDAISGFNSX-UHFFFAOYSA-N 0.000 claims description 9
- NTHWMYGWWRZVTN-UHFFFAOYSA-N sodium silicate Chemical compound [Na+].[Na+].[O-][Si]([O-])=O NTHWMYGWWRZVTN-UHFFFAOYSA-N 0.000 claims description 9
- 239000010959 steel Substances 0.000 claims description 9
- 238000001291 vacuum drying Methods 0.000 claims description 9
- 239000000395 magnesium oxide Substances 0.000 claims description 8
- 229910052779 Neodymium Inorganic materials 0.000 claims description 7
- 238000004458 analytical method Methods 0.000 claims description 7
- -1 magnesium-gadolinium-scandium Chemical compound 0.000 claims description 7
- AXZKOIWUVFPNLO-UHFFFAOYSA-N magnesium;oxygen(2-) Chemical compound [O-2].[Mg+2] AXZKOIWUVFPNLO-UHFFFAOYSA-N 0.000 claims description 7
- 238000003756 stirring Methods 0.000 claims description 7
- 229910001297 Zn alloy Inorganic materials 0.000 claims description 6
- PGTXKIZLOWULDJ-UHFFFAOYSA-N [Mg].[Zn] Chemical compound [Mg].[Zn] PGTXKIZLOWULDJ-UHFFFAOYSA-N 0.000 claims description 6
- 238000006243 chemical reaction Methods 0.000 claims description 6
- 238000001816 cooling Methods 0.000 claims description 6
- 238000005520 cutting process Methods 0.000 claims description 6
- QEFYFXOXNSNQGX-UHFFFAOYSA-N neodymium atom Chemical compound [Nd] QEFYFXOXNSNQGX-UHFFFAOYSA-N 0.000 claims description 6
- 238000005498 polishing Methods 0.000 claims description 6
- 239000002893 slag Substances 0.000 claims description 6
- 238000005406 washing Methods 0.000 claims description 6
- 238000005303 weighing Methods 0.000 claims description 6
- QCWXUUIWCKQGHC-UHFFFAOYSA-N Zirconium Chemical compound [Zr] QCWXUUIWCKQGHC-UHFFFAOYSA-N 0.000 claims description 5
- 238000005275 alloying Methods 0.000 claims description 4
- 230000005540 biological transmission Effects 0.000 claims description 4
- 244000137852 Petrea volubilis Species 0.000 claims description 3
- 239000011247 coating layer Substances 0.000 claims description 3
- 238000000576 coating method Methods 0.000 claims description 3
- 230000001276 controlling effect Effects 0.000 claims description 3
- 238000011049 filling Methods 0.000 claims description 3
- 230000002431 foraging effect Effects 0.000 claims description 3
- 230000006698 induction Effects 0.000 claims description 3
- 238000005086 pumping Methods 0.000 claims description 3
- 230000001105 regulatory effect Effects 0.000 claims description 3
- 239000004576 sand Substances 0.000 claims description 3
- 238000007789 sealing Methods 0.000 claims description 3
- 239000002002 slurry Substances 0.000 claims description 3
- 239000010935 stainless steel Substances 0.000 claims description 3
- 229910001220 stainless steel Inorganic materials 0.000 claims description 3
- 239000000725 suspension Substances 0.000 claims description 2
- 229910000861 Mg alloy Inorganic materials 0.000 abstract description 17
- 238000005728 strengthening Methods 0.000 abstract description 12
- 229910052761 rare earth metal Inorganic materials 0.000 abstract description 6
- 150000002910 rare earth metals Chemical class 0.000 abstract description 4
- 229910001093 Zr alloy Inorganic materials 0.000 abstract description 2
- 238000005204 segregation Methods 0.000 abstract description 2
- 239000007787 solid Substances 0.000 description 8
- 230000000694 effects Effects 0.000 description 6
- 239000000243 solution Substances 0.000 description 6
- 239000007788 liquid Substances 0.000 description 4
- FYYHWMGAXLPEAU-OUBTZVSYSA-N magnesium-25 atom Chemical compound [25Mg] FYYHWMGAXLPEAU-OUBTZVSYSA-N 0.000 description 3
- 238000011160 research Methods 0.000 description 3
- 239000007789 gas Substances 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 229910052684 Cerium Inorganic materials 0.000 description 1
- 229910003023 Mg-Al Inorganic materials 0.000 description 1
- 229910020489 SiO3 Inorganic materials 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 229910002056 binary alloy Inorganic materials 0.000 description 1
- 238000012512 characterization method Methods 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 238000013016 damping Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 230000018109 developmental process Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000005670 electromagnetic radiation Effects 0.000 description 1
- 238000004134 energy conservation Methods 0.000 description 1
- ZZUFCTLCJUWOSV-UHFFFAOYSA-N furosemide Chemical compound C1=C(Cl)C(S(=O)(=O)N)=CC(C(O)=O)=C1NCC1=CC=CO1 ZZUFCTLCJUWOSV-UHFFFAOYSA-N 0.000 description 1
- 230000005484 gravity Effects 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 238000004064 recycling Methods 0.000 description 1
- 239000006104 solid solution Substances 0.000 description 1
- 230000035882 stress Effects 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 229910052727 yttrium Inorganic materials 0.000 description 1
- 239000011701 zinc Substances 0.000 description 1
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C1/00—Making non-ferrous alloys
- C22C1/02—Making non-ferrous alloys by melting
- C22C1/03—Making non-ferrous alloys by melting using master alloys
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D7/00—Casting ingots, e.g. from ferrous metals
- B22D7/005—Casting ingots, e.g. from ferrous metals from non-ferrous metals
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C23/00—Alloys based on magnesium
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Physical Vapour Deposition (AREA)
Abstract
The invention relates to a method for preparing a high-strength Sc-containing cast magnesium-gadolinium alloy, which belongs to the technical field of magnesium-gadolinium alloy preparation and solves the technical problem of poor ductility and toughness of the magnesium-gadolinium alloy in the prior art, trace Sc and Zr elements are compositely added to obviously inhibit the growth of alloy grains at a higher temperature, and the homogenization treatment is carried out for 6-9h at 525 ℃ through 520-plus, so that the component segregation of Mg-Gd-Nd rare earth magnesium alloy is eliminated, the internal stress is eliminated, and particularly, the growth of a strengthening phase GdSc phase in the Mg-Gd-Nd-Sc-Zr alloy in a matrix and the grains can be effectively promoted, so that the comprehensive mechanical property is improved, the tensile strength of the prepared cast magnesium alloy reaches 337MPa, the yield strength reaches 212MPa, the elongation reaches 6.5%, and the product purity reaches 99.5%.
Description
Technical Field
The invention belongs to the technical field of preparation of magnesium-gadolinium alloys, and particularly relates to a method for preparing a high-strength Sc-containing cast magnesium-gadolinium alloy.
Background
The magnesium alloy is used as the lightest metal engineering structural material, and is particularly suitable for the application in the fields of automobiles, computers, communication, instruments and meters, light industry of household appliances, military affairs and the like because of the characteristics of light specific gravity, energy conservation, consumption reduction, high specific strength-to-rigidity, strong damping vibration attenuation and dryness reduction capability, excellent liquid forming performance, electromagnetic radiation shielding and easy recycling. A series of magnesium alloys such as Mg-Al, Mg-Zn and the like are developed and applied to various fields, but the further popularization and application of the magnesium alloys are restricted by the lower absolute strength, insufficient toughness and lower high-temperature resistance.
Researchers find that rare earth such as Gd, Ce, Y and the like is added into the magnesium alloy to improve the high-temperature strength and high-temperature creep resistance of the alloy and improve the casting performance, and the research and the application of adding rare earth elements to strengthen the magnesium alloy are started from the 20 th century in the 70 s at home and abroad; however, the density and cost of magnesium alloy can be greatly improved while high performance is brought by high content of magnesium rare earth alloy, and in order to improve the application universality of magnesium alloy, reducing the addition of rare earth as much as possible and improving the toughness and heat resistance of magnesium alloy to the maximum extent becomes a hot spot in magnesium alloy research.
The maximum solid solubility of gadolinium in magnesium is 23.5wt.%, and the solid solubility can rapidly decrease to 3.82wt.% with the decrease of temperature to 200 ℃, so that gadolinium is an alloying element with a very remarkable aging strengthening effect, and has double effects of solid solution strengthening and aging strengthening. When the effective temperature of the Mg-Gd alloy is higher than 523K, the aging strengthening can occur within 0.5-1 h, and when the temperature is lower than 473K, the aging strengthening effect can be achieved for a long time; the discoid second phases beta ' and beta ' ' which are separated out from the cylindrical surface in the direction of (11-20) have the best resistance to basal plane dislocation slip, and the strengthening effect is the best, which is the main reason for the aging strengthening effect of the Mg-Gd alloy; relevant researches show that the addition of gadolinium in the magnesium-gadolinium binary alloy can generate a remarkable aging strengthening effect only when the addition of gadolinium reaches at least 10%, but the simple addition of gadolinium not only can increase the alloy cost, but also can increase the alloy density and reduce the plastic toughness at room temperature, so that the addition of elements with lower price and density can reduce the consumption of gadolinium in the magnesium alloy, and the development of the magnesium alloy with better plastic toughness is particularly important.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and solve the technical problem of poor plastic toughness of the magnesium gadolinium alloy in the prior art, and provides a method for preparing high-strength Sc-containing cast magnesium gadolinium alloy. According to the invention, the growth of alloy grains at a higher temperature can be obviously inhibited by the compound addition of trace Sc and Zr elements, and the component segregation of the Mg-Gd-Nd rare earth magnesium alloy can be eliminated and the internal stress can be eliminated by homogenizing at 525 ℃ for 6-9h, so that the growth of a strengthening phase GdSc phase in the Mg-Gd-Nd-Sc-Zr alloy in a matrix and the grains can be effectively promoted, and the comprehensive mechanical property can be improved.
In order to solve the problems, the technical scheme of the invention is as follows:
a method for preparing high-strength Sc-containing cast magnesium-gadolinium alloy comprises the following steps:
s1, raw material pretreatment:
s1-1, cutting into blocks: respectively placing magnesium, a magnesium-gadolinium intermediate alloy, a magnesium-neodymium intermediate alloy, a magnesium-zirconium intermediate alloy and a magnesium-scandium intermediate alloy block on a steel flat plate, and mechanically cutting the steel flat plate to prepare a block raw material, wherein the size of the block raw material is as follows: length 10mm, width 10mm, height 10 mm;
s1-2, polishing the surfaces of the block raw materials obtained in the step S1-1 by using sand paper, and then cleaning by using absolute ethyl alcohol;
s1-3, placing the block raw material cleaned by the absolute ethyl alcohol in a vacuum drying oven for preheating and drying, wherein the preheating and drying temperature is 100 ℃, the vacuum degree is 2Pa, and the drying time is 40 min;
s2, preparing a coating agent:
weighing 50g +/-1 g of magnesium oxide, 10mL +/-1 mL of water glass, 500mL +/-1 mL of deionized water, adding the magnesium oxide, the water glass and the deionized water into a slurry mixer for stirring at the stirring revolution of 50r/min for 80min to prepare a milky suspension coating agent;
s3, preparing an open-close type mould:
the cavity of the open-close type mould is in a cubic shape, the open-close type mould is made of stainless steel, and the roughness of the surface of the cavity is Ra0.08-0.16 mu m;
s4, smelting a magnesium-zinc alloy ingot:
s4-1, cleaning and preheating an opening and closing die and coating a coating agent on the surface of a cavity:
firstly, cleaning the surface of a cavity of an opening and closing mold by using absolute ethyl alcohol to clean the surface of the cavity;
then, the coating agent prepared in the step S2 is uniformly coated on the surface of the cavity of the opening and closing die, and the thickness of the coating layer is 0.5 mm;
finally, placing the opening and closing die in a drying box for preheating, wherein the preheating temperature is 150 ℃;
s4-2, opening the vacuum melting furnace, cleaning the interior of the melting crucible, and then cleaning the interior of the melting crucible by using absolute ethyl alcohol to clean the interior of the melting crucible;
s4-3, weighing 1290g +/-lg of the magnesium block, 165g +/-lg of the magnesium-gadolinium intermediate alloy, 30g +/-lg of the magnesium-neodymium intermediate alloy, 7.5g +/-lg of the magnesium-zirconium intermediate alloy and 7.5g +/-lg of the magnesium-scandium intermediate alloy after the raw material pretreatment in the step S1, and placing the weighed magnesium block, the magnesium-gadolinium intermediate alloy, the magnesium-neodymium intermediate alloy, the magnesium-zirconium intermediate alloy and the magnesium-scandium intermediate alloy at the bottom of a smelting crucible;
s4-4, closing the vacuum melting furnace and sealing; starting a vacuum pump, and pumping air in the furnace chamber until the pressure in the furnace chamber reaches 2 Pa; starting a medium-frequency induction heater to start heating, wherein the heating temperature is 750 +/-1 ℃, and the heating time is 60 min;
s4-5, communicating the bottom of the smelting crucible with a bottom blowing pipe, and filling argon into the vertical vacuum smelting furnace, wherein the bottom blowing speed of the argon is 200 cm3Min, regulating and controlling the pressure in the furnace chamber to be constant at 1 atmosphere by using an air outlet valve; the magnesium, gadolinium, neodymium, zirconium and scandium are subjected to alloying reaction in the smelting process, and the reaction equation is as follows:
in the formula: mg (magnesium)5Gd is a magnesium gadolinium eutectic phase, Mg12Nd is magnesium-neodymiumThe eutectic phase is MgGdSc which is a magnesium gadolinium scandium eutectic phase, MgNdSc which is a magnesium neodymium scandium eutectic phase, and a-Mg which is a magnesium matrix phase;
smelting to obtain an alloy solution, reducing the heating temperature to 720 +/-1 ℃, and keeping the temperature at the constant temperature for 10 min;
s4-6, casting: closing the bottom blowing motor, opening the vertical vacuum smelting furnace, removing slag on the surface of the solution in the smelting crucible, and casting until the molten slag is fully cast by aiming at a preheated open-close type mould pouring gate;
s4-7, cooling: embedding the open-close type die cast with the alloy solution into fine sand and cooling to 25 ℃;
s4-8, opening the mould: opening the open-close type mold, and taking out the casting to obtain a magnesium-gadolinium alloy ingot;
s5, carrying out heat treatment on the magnesium-gadolinium alloy ingot:
homogenizing: placing the prepared magnesium-gadolinium alloy ingot in a heat treatment furnace for homogenization treatment, wherein the heating temperature is 520-525 ℃, the constant temperature and heat preservation time is 6-8h, introducing argon for protection, and the argon introduction speed is 100cm3Min; after constant temperature and heat preservation, rapidly putting the magnesium-gadolinium alloy cast ingot into warm water at 35 ℃ for quenching treatment, wherein the quenching time is 30 s;
aging treatment: placing the homogenized magnesium-gadolinium alloy ingot in a heat treatment furnace for aging treatment, wherein the aging temperature is 250 ℃, and the constant temperature and heat preservation time is 1.5 h; then rapidly placing the magnesium-gadolinium alloy ingot in warm water at 30 ℃ for quenching treatment, wherein the quenching time is 30s, and obtaining a high-strength Sc-containing cast magnesium-gadolinium alloy ingot after quenching;
s6, cleaning and washing the high-strength Sc-containing cast magnesium-gadolinium alloy ingot: placing the high-strength Sc-containing cast magnesium-gadolinium alloy ingot prepared in the step S5 on a steel flat plate, and polishing the surface of the ingot by using abrasive paper to make the surface smooth; then, washing each surface by absolute ethyl alcohol to clean each surface;
s7, vacuum drying of the high-strength Sc-containing cast magnesium-gadolinium alloy ingot: placing the high-strength Sc-containing cast magnesium-gadolinium alloy ingot cleaned in the step S6 in a vacuum drying oven, wherein the vacuum degree is 2Pa, the drying temperature is 100 ℃, and the drying time is 10 min;
and S8, detecting, analyzing and characterizing.
Further, in the step S8, the microstructure, the metallographic structure, and the mechanical properties of the prepared high-strength scandium-containing magnesium-zinc alloy ingot sample are detected, analyzed, and characterized.
Furthermore, metallographic structure analysis is carried out by a metallographic analyzer and a transmission electron microscope, and tensile strength analysis is carried out by a microcomputer control electronic universal tester.
Compared with the prior art, the invention has the beneficial effects that:
aiming at the technical problem of low strength of cast magnesium alloy in the prior art, magnesium, gadolinium, neodymium, scandium and zirconium are added in the smelting process to enhance the mechanical property of the cast magnesium alloy, the tensile strength of the prepared cast magnesium alloy reaches 337MPa, the yield strength reaches 212MPa, the elongation reaches 6.5%, and the purity of the product reaches 99.5%. The preparation method has advanced process and precise and detailed data, and is an advanced method for preparing the high-strength magnesium-gadolinium alloy ingot.
Drawings
FIG. 1 is a metallographic structure morphology of a cross section of a high-strength Sc-containing cast magnesium-gadolinium alloy;
FIG. 2 is a cross section transmission dark field diagram of a high-strength Sc-containing cast magnesium-gadolinium alloy;
FIG. 3 is a comparison graph of mechanical properties of high-strength Sc-containing cast magnesium-gadolinium alloy in an as-cast state and an aged state.
Detailed Description
The invention is described in further detail below with reference to the figures and examples.
The chemical materials used were: magnesium, magnesium-30% gadolinium intermediate alloy, magnesium-25% neodymium intermediate alloy, magnesium-25% zirconium intermediate alloy, magnesium-10% scandium intermediate alloy, water glass, deionized water and argon, and the preparation amounts of the magnesium, the magnesium-30% gadolinium intermediate alloy, the magnesium-25% neodymium intermediate alloy, the magnesium-10% scandium intermediate alloy, the water glass, the deionized water and the argon are as follows (in grams, milliliters and cm)3As measured units):
mg, the purity of which is 99.99 percent, and 1290g of solid blocks;
magnesium-gadolinium intermediate alloy Mg-30% Gd, purity 30%, solid block 165 g;
magnesium-neodymium intermediate alloy Mg-25% Nd, purity 25%, solid block 30 g;
the magnesium-zirconium intermediate alloy comprises Mg-25% of Zr, the purity is 25%, and the solid block is 7.5 g;
the magnesium-scandium master alloy comprises Mg-10% of Sc, 10% of purity and 7.5g of solid block;
water glass: na (Na)2SiO3·9H210mL of O liquid;
magnesium oxide: 50g of MgO solid powder;
anhydrous ethanol: c2H51000mL of OH liquid;
deionized water: h21000mL of O liquid;
argon gas: ar gas 800000cm3。
A method for preparing high-strength Sc-containing cast magnesium-gadolinium alloy comprises the following steps:
s1, raw material pretreatment:
s1-1, cutting into blocks: respectively placing magnesium, a magnesium-gadolinium intermediate alloy, a magnesium-neodymium intermediate alloy, a magnesium-zirconium intermediate alloy and a magnesium-scandium intermediate alloy block on a steel flat plate, and mechanically cutting the steel flat plate to prepare a block raw material, wherein the size of the block raw material is as follows: length 10mm, width 10mm, height 10 mm;
s1-2, polishing the surfaces of the block raw materials obtained in the step S1-1 by using sand paper, and then cleaning by using absolute ethyl alcohol;
s1-3, placing the block raw material cleaned by the absolute ethyl alcohol in a vacuum drying oven for preheating and drying, wherein the preheating and drying temperature is 100 ℃, the vacuum degree is 2Pa, and the drying time is 40 min;
s2, preparing a coating agent:
weighing 50g of magnesium oxide, 10mL of water glass and 500mL of deionized water, adding the magnesium oxide, the water glass and the deionized water into a slurry mixer for stirring, wherein the stirring revolution is 50r/min, and the stirring time is 80min, so as to prepare a milky suspended coating agent;
s3, preparing an open-close type mould:
the cavity of the open-close type mould is in a cubic shape, the open-close type mould is made of stainless steel, and the roughness of the surface of the cavity is Ra0.08 mu m;
s4, smelting a magnesium-zinc alloy ingot:
s4-1, cleaning and preheating an opening and closing die and coating a coating agent on the surface of a cavity:
firstly, cleaning the surface of a cavity of an opening and closing mold by using absolute ethyl alcohol to clean the surface of the cavity;
then, the coating agent prepared in the step S2 is uniformly coated on the surface of the cavity of the opening and closing die, and the thickness of the coating layer is 0.5 mm;
finally, placing the opening and closing die in a drying box for preheating, wherein the preheating temperature is 150 ℃;
s4-2, opening the vacuum melting furnace, cleaning the interior of the melting crucible, and then cleaning the interior of the melting crucible by using absolute ethyl alcohol to clean the interior of the melting crucible;
s4-3, weighing 1290g of magnesium block, 165g of magnesium-gadolinium intermediate alloy, 30g of magnesium-neodymium intermediate alloy, 7.5g of magnesium-zirconium intermediate alloy and 7.5g of magnesium-scandium intermediate alloy after the raw material pretreatment in the step S1, and placing the weighed magnesium block, the magnesium-gadolinium intermediate alloy, the magnesium-neodymium intermediate alloy, the magnesium-zirconium intermediate alloy and the magnesium-scandium intermediate alloy at the bottom of a smelting crucible;
s4-4, closing the vacuum melting furnace and sealing; starting a vacuum pump, and pumping air in the furnace chamber until the pressure in the furnace chamber reaches 2 Pa; starting the medium-frequency induction heater to start heating, wherein the heating temperature is 750 ℃, and the heating time is 60 min;
s4-5, communicating the bottom of the smelting crucible with a bottom blowing pipe, and filling argon into the vertical vacuum smelting furnace, wherein the bottom blowing speed of the argon is 200 cm3Min, regulating and controlling the pressure in the furnace chamber to be constant at 1 atmosphere by using an air outlet valve; the magnesium, gadolinium, neodymium, zirconium and scandium are subjected to alloying reaction in the smelting process, and the reaction equation is as follows:
in the formula: mg (magnesium)5Gd is a magnesium gadolinium eutectic phase, Mg12Nd is a magnesium-neodymium eutectic phase, MgGdSc is a magnesium-gadolinium-scandium eutectic phase, MgNdSc is a magnesium-neodymium-scandium eutectic phase, and a-Mg is a magnesium matrix phase;
smelting to obtain an alloy solution, reducing the heating temperature to 720 ℃, and keeping the temperature at the constant temperature for 10 min;
s4-6, casting: closing the bottom blowing motor, opening the vertical vacuum smelting furnace, removing slag on the surface of the solution in the smelting crucible, and casting until the molten slag is fully cast by aiming at a preheated open-close type mould pouring gate;
s4-7, cooling: embedding the open-close type die cast with the alloy solution into fine sand and cooling to 25 ℃;
s4-8, opening the mould: opening the open-close type mold, and taking out the casting to obtain a magnesium-gadolinium alloy ingot;
s5, carrying out heat treatment on the magnesium-gadolinium alloy ingot:
homogenizing: placing the prepared magnesium-gadolinium alloy ingot in a heat treatment furnace for homogenization treatment, wherein the heating temperature is 520, the constant temperature and heat preservation time is 6h, introducing argon for protection, and the argon introduction speed is 100cm3Min; after constant temperature and heat preservation, rapidly putting the magnesium-gadolinium alloy cast ingot into warm water at 35 ℃ for quenching treatment, wherein the quenching time is 30 s;
aging treatment: placing the homogenized magnesium-gadolinium alloy ingot in a heat treatment furnace for aging treatment, wherein the aging temperature is 250 ℃, and the constant temperature and heat preservation time is 1.5 h; then rapidly placing the magnesium-gadolinium alloy ingot in warm water at 30 ℃ for quenching treatment, wherein the quenching time is 30s, and obtaining a high-strength Sc-containing cast magnesium-gadolinium alloy ingot after quenching;
s6, cleaning and washing the high-strength Sc-containing cast magnesium-gadolinium alloy ingot: placing the high-strength Sc-containing cast magnesium-gadolinium alloy ingot prepared in the step S5 on a steel flat plate, and polishing the surface of the ingot by using abrasive paper to make the surface smooth; then, washing each surface by absolute ethyl alcohol to clean each surface;
s7, vacuum drying of the high-strength Sc-containing cast magnesium-gadolinium alloy ingot: placing the high-strength Sc-containing cast magnesium-gadolinium alloy ingot cleaned in the step S6 in a vacuum drying oven, wherein the vacuum degree is 2Pa, the drying temperature is 100 ℃, and the drying time is 10 min;
s8, detection, analysis and characterization:
detecting, analyzing and representing the microstructure, metallographic structure and mechanical properties of the prepared high-strength scandium-containing magnesium-zinc alloy ingot casting sample; metallographic structure analysis is carried out by a metallographic analyzer and a transmission electron microscope, and tensile strength analysis is carried out by a microcomputer control electronic universal tester.
As shown in figure 1, the grain size is small, the grains mainly contain two phases, namely a matrix phase a-Mg phase and a high-temperature resistant strengthening phase MgGdSc, and MgNdSc phases are uniformly distributed in the matrix.
As shown in fig. 2, a dense strengthening phase is precipitated in the matrix during aging.
As shown in FIG. 3, before heat treatment (as-cast state), the tensile strength of the magnesium-gadolinium alloy ingot is 212MPa, the yield strength is 107MPa, and the elongation is 7.2%; after heat treatment (aged state), the magnesium-gadolinium alloy ingot has the tensile strength of 337MPa, the yield strength of 212MPa and the elongation of 6.5 percent.
The above description is only for the specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are included in the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the appended claims.
Claims (3)
1. A method for preparing high-strength Sc-containing cast magnesium-gadolinium alloy is characterized by comprising the following steps:
s1, raw material pretreatment:
s1-1, cutting into blocks: respectively placing magnesium, a magnesium-gadolinium intermediate alloy, a magnesium-neodymium intermediate alloy, a magnesium-zirconium intermediate alloy and a magnesium-scandium intermediate alloy block on a steel flat plate, and mechanically cutting the steel flat plate to prepare a block raw material, wherein the size of the block raw material is as follows: length 10mm, width 10mm, height 10 mm;
s1-2, polishing the surfaces of the block raw materials obtained in the step S1-1 by using sand paper, and then cleaning by using absolute ethyl alcohol;
s1-3, placing the block raw material cleaned by the absolute ethyl alcohol in a vacuum drying oven for preheating and drying, wherein the preheating and drying temperature is 100 ℃, the vacuum degree is 2Pa, and the drying time is 40 min;
s2, preparing a coating agent:
weighing 50g +/-1 g of magnesium oxide, 10mL +/-1 mL of water glass, 500mL +/-1 mL of deionized water, adding the magnesium oxide, the water glass and the deionized water into a slurry mixer for stirring at the stirring revolution of 50r/min for 80min to prepare a milky suspension coating agent;
s3, preparing an open-close type mould:
the cavity of the open-close type mould is in a cubic shape, the open-close type mould is made of stainless steel, and the roughness of the surface of the cavity is Ra0.08-0.16 mu m;
s4, smelting a magnesium-zinc alloy ingot:
s4-1, cleaning and preheating an opening and closing die and coating a coating agent on the surface of a cavity:
firstly, cleaning the surface of a cavity of an opening and closing mold by using absolute ethyl alcohol to clean the surface of the cavity;
then, the coating agent prepared in the step S2 is uniformly coated on the surface of the cavity of the opening and closing die, and the thickness of the coating layer is 0.5 mm;
finally, placing the opening and closing die in a drying box for preheating, wherein the preheating temperature is 150 ℃;
s4-2, opening the vacuum melting furnace, cleaning the interior of the melting crucible, and then cleaning the interior of the melting crucible by using absolute ethyl alcohol to clean the interior of the melting crucible;
s4-3, weighing 1290g +/-lg of the magnesium block, 165g +/-lg of the magnesium-gadolinium intermediate alloy, 30g +/-lg of the magnesium-neodymium intermediate alloy, 7.5g +/-lg of the magnesium-zirconium intermediate alloy and 7.5g +/-lg of the magnesium-scandium intermediate alloy after the raw material pretreatment in the step S1, and placing the weighed magnesium block, the magnesium-gadolinium intermediate alloy, the magnesium-neodymium intermediate alloy, the magnesium-zirconium intermediate alloy and the magnesium-scandium intermediate alloy at the bottom of a smelting crucible;
s4-4, closing the vacuum melting furnace and sealing; starting a vacuum pump, and pumping air in the furnace chamber until the pressure in the furnace chamber reaches 2 Pa; starting a medium-frequency induction heater to start heating, wherein the heating temperature is 750 +/-1 ℃, and the heating time is 60 min;
s4-5, communicating the bottom of the smelting crucible with a bottom blowing pipe, and filling argon into the vertical vacuum smelting furnace, wherein the bottom blowing speed of the argon is 200 cm3Min, regulating and controlling the pressure in the furnace chamber to be constant at 1 atmosphere by using an air outlet valve; the magnesium, gadolinium, neodymium, zirconium and scandium are subjected to alloying reaction in the smelting process, and the reaction equation is as follows:
in the formula: mg (magnesium)5Gd is a magnesium gadolinium eutectic phase, Mg12Nd is a magnesium-neodymium eutectic phase, MgGdSc is a magnesium-gadolinium-scandium eutectic phase, MgNdSc is a magnesium-neodymium-scandium eutectic phase, and a-Mg is a magnesium matrix phase;
smelting to obtain an alloy solution, reducing the heating temperature to 720 +/-1 ℃, and keeping the temperature at the constant temperature for 10 min;
s4-6, casting: closing the bottom blowing motor, opening the vertical vacuum smelting furnace, removing slag on the surface of the solution in the smelting crucible, and casting until the molten slag is fully cast by aiming at a preheated open-close type mould pouring gate;
s4-7, cooling: embedding the open-close type die cast with the alloy solution into fine sand and cooling to 25 ℃;
s4-8, opening the mould: opening the open-close type mold, and taking out the casting to obtain a magnesium-gadolinium alloy ingot;
s5, carrying out heat treatment on the magnesium-gadolinium alloy ingot:
homogenizing: placing the prepared magnesium-gadolinium alloy ingot in a heat treatment furnace for homogenization treatment, wherein the heating temperature is 520-525 ℃, the constant temperature and heat preservation time is 6-8h, introducing argon for protection, and the argon introduction speed is 100cm3Min; after constant temperature and heat preservation, rapidly putting the magnesium-gadolinium alloy cast ingot into warm water at 35 ℃ for quenching treatment, wherein the quenching time is 30 s;
aging treatment: placing the homogenized magnesium-gadolinium alloy ingot in a heat treatment furnace for aging treatment, wherein the aging temperature is 250 ℃, and the constant temperature and heat preservation time is 1.5 h; then rapidly placing the magnesium-gadolinium alloy ingot in warm water at 30 ℃ for quenching treatment, wherein the quenching time is 30s, and obtaining a high-strength Sc-containing cast magnesium-gadolinium alloy ingot after quenching;
s6, cleaning and washing the high-strength Sc-containing cast magnesium-gadolinium alloy ingot: placing the high-strength Sc-containing cast magnesium-gadolinium alloy ingot prepared in the step S5 on a steel flat plate, and polishing the surface of the ingot by using abrasive paper to make the surface smooth; then, washing each surface by absolute ethyl alcohol to clean each surface;
s7, vacuum drying of the high-strength Sc-containing cast magnesium-gadolinium alloy ingot: placing the high-strength Sc-containing cast magnesium-gadolinium alloy ingot cleaned in the step S6 in a vacuum drying oven, wherein the vacuum degree is 2Pa, the drying temperature is 100 ℃, and the drying time is 10 min;
and S8, detecting, analyzing and characterizing.
2. A process for the preparation of a high strength Sc-containing cast magnesium gadolinium alloy as claimed in claim 1 wherein: and in the step S8, detecting, analyzing and representing the microstructure, the metallographic structure and the mechanical properties of the prepared high-strength scandium-containing magnesium-zinc alloy ingot casting sample.
3. A method for preparing a high strength Sc-containing cast magnesium gadolinium alloy according to claim 2 wherein: metallographic structure analysis is carried out by a metallographic analyzer and a transmission electron microscope, and tensile strength analysis is carried out by a microcomputer control electronic universal tester.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111046790.3A CN113913634A (en) | 2021-09-08 | 2021-09-08 | Method for preparing high-strength Sc-containing cast magnesium-gadolinium alloy |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111046790.3A CN113913634A (en) | 2021-09-08 | 2021-09-08 | Method for preparing high-strength Sc-containing cast magnesium-gadolinium alloy |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN113913634A true CN113913634A (en) | 2022-01-11 |
Family
ID=79234306
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111046790.3A Pending CN113913634A (en) | 2021-09-08 | 2021-09-08 | Method for preparing high-strength Sc-containing cast magnesium-gadolinium alloy |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113913634A (en) |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2007107286A2 (en) * | 2006-03-18 | 2007-09-27 | Acrostak Corp. Bvi | Magnesium-based alloy with improved combination of mechanical and corrosion characteristics |
| CN102892909A (en) * | 2010-03-25 | 2013-01-23 | 镁电子有限公司 | Magnesium alloys containing heavy rare earths |
| CN107760949A (en) * | 2017-09-28 | 2018-03-06 | 中北大学 | A kind of preparation method of the high tenacity casting magnesium alloy ingot of complex intensifying |
| CN109022983A (en) * | 2018-08-23 | 2018-12-18 | 中国科学院长春应用化学研究所 | A kind of high-strength-toughness magnesium alloy and preparation method thereof containing Sc |
| CN112410632A (en) * | 2020-11-20 | 2021-02-26 | 中国科学院长春应用化学研究所 | Mg-Gd-Y-Nd high-strength rare earth magnesium alloy and preparation method thereof |
-
2021
- 2021-09-08 CN CN202111046790.3A patent/CN113913634A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2007107286A2 (en) * | 2006-03-18 | 2007-09-27 | Acrostak Corp. Bvi | Magnesium-based alloy with improved combination of mechanical and corrosion characteristics |
| CN102892909A (en) * | 2010-03-25 | 2013-01-23 | 镁电子有限公司 | Magnesium alloys containing heavy rare earths |
| CN107760949A (en) * | 2017-09-28 | 2018-03-06 | 中北大学 | A kind of preparation method of the high tenacity casting magnesium alloy ingot of complex intensifying |
| CN109022983A (en) * | 2018-08-23 | 2018-12-18 | 中国科学院长春应用化学研究所 | A kind of high-strength-toughness magnesium alloy and preparation method thereof containing Sc |
| CN112410632A (en) * | 2020-11-20 | 2021-02-26 | 中国科学院长春应用化学研究所 | Mg-Gd-Y-Nd high-strength rare earth magnesium alloy and preparation method thereof |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN108467962B (en) | Preparation method of magnesium-zinc-yttrium quasicrystal and boron carbide mixed enhanced magnesium-based composite material | |
| CN107760949B (en) | A kind of preparation method of the high tenacity casting magnesium alloy ingot of complex intensifying | |
| CN102534330B (en) | High-strength cast magnesium alloy and preparation method thereof | |
| CN103074520A (en) | Er-containing high-niobium Ti-Al intermetallic compound material and preparation method thereof | |
| CN105506326A (en) | Preparation method of long-period-structure-reinforced magnesium-zirconium alloy ingot | |
| CN109468496B (en) | Heat-resistant die-casting aluminum alloy and preparation method thereof | |
| CN103290287A (en) | Rare earth magnesium-lithium alloy sheet and preparation method thereof | |
| CN112111685A (en) | Wear-resistant refractory high-entropy alloy and preparation method thereof | |
| Zhengjun et al. | Synthesis and refinement performance of the novel Al-Ti-B-RE master alloy grain refiner | |
| CN109022981A (en) | A kind of preparation method of high-strength casting magnesium-zinc alloy ingot | |
| CN114250393A (en) | High-strength high-modulus biphase magnesium-lithium alloy and preparation method thereof | |
| CN108611505B (en) | A kind of preparation method of spontaneous quasi-crystalline substance enhanced magnesium alloy material | |
| CN114393197A (en) | Directional solidification preparation method of high-tin-content high-plasticity copper-tin alloy | |
| CN113913635A (en) | Device and method for preparing scandium-containing high-strength cast magnesium-zinc alloy | |
| CN107119203B (en) | A kind of method for preparing Yb, La and SiC composite inoculating A356.2 alloys | |
| CN113913634A (en) | Method for preparing high-strength Sc-containing cast magnesium-gadolinium alloy | |
| CN109252078B (en) | Preparation method of high-strength titanium-containing cast magnesium alloy | |
| CN109295329B (en) | Preparation method of long-period structure reinforced magnesium-tin alloy plate | |
| CN110983146B (en) | Preparation method of large-size manganese-containing high-entropy alloy ingot | |
| CN113667873A (en) | Preparation method of high-strength and high-toughness scandium-containing heat-resistant magnesium-gadolinium alloy ingot | |
| CN107034380B (en) | It is a kind of to prepare nano SiC, the method for Yb enhancing A356.2 alloys | |
| CN109182858A (en) | One kind heat resistance magnesium alloy containing Ho and preparation method thereof | |
| CN102994785B (en) | Method for smelting hydrogen storage alloy containing titanium from BaZrO3 refractory material by vacuum induction | |
| CN102241404B (en) | Method for vacuum casting Fe2B compound | |
| CN105296831A (en) | High-room-temperature-elongation wrought magnesium alloy and preparation method thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| CB03 | Change of inventor or designer information |
Inventor after: Hou Hua Inventor after: Lu Ruopeng Inventor after: Yao Keyu Inventor after: Zhao Yuhong Inventor after: Jiao Kai Inventor after: Yan Xi Inventor after: Li Nanting Inventor after: Xu Xiaolong Inventor before: Lu Ruopeng Inventor before: Zhao Yuhong Inventor before: Yao Keyu Inventor before: Hou Hua Inventor before: Jiao Kai Inventor before: Yan Xi Inventor before: Li Nanting |
|
| CB03 | Change of inventor or designer information | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20220111 |
|
| RJ01 | Rejection of invention patent application after publication |