29 results about "Mg element" patented technology

The present invention relates to the technical field of other processing of metals. Disclosed are a free-machining titanium material and a preparation process therefor. The free-machining titanium material comprises: a matrix component group and free-machining component groups, wherein at least one of the free-machining component groups is added to the matrix component group; the matrix component group comprises the following components in percentage by mass: 0-1.0% of Fe, 0-0.08% of N, 0-0.02% of H, 0-0.50% of O, 0-8.0% of Al, 0-15.0% of V, and the balance being titanium and inevitable impurities; and the free-machining component groups are an RE element and S element group, a Cu element and S element group, a Zr element group, a C element group, a B element group, and an Mg element group, respectively. The preparation process involves producing the described free-machining titanium material by using any one of the following three methods: vacuum arc remelting, vacuum floating melting, and powder metallurgy. The present invention solves the technical problem of how to further improve the machinability of titanium materials.

The invention belongs to the technical field of metal materials, and particularly relates to a high-strength corrosion-resistant heat-treatment-free die-casting aluminum alloy and a preparation method thereof. The aluminum alloy comprises, by mass, 5.5%-7.1% of Mg, 2.5%-3.5% of Si, 0.5%-0.75% of Mn, 0.11%-0.7% of Cu, 0.08%-0.15% of Fe, 0.05%-0.1% of Mo, 0.02%-0.05% of V, 0.01%-0.05% of Zr, 0.03%-0.09% of Y and the balance Al and inevitable impurity elements, the content of a single impurity element is smaller than or equal to 0.02%, and the total content of the impurity elements is smaller than or equal to 0.2%. And the mass ratio of the Mg element to the Cu element in the aluminum alloy components is in the range of (10: 1)-(50: 1). The heat-treatment-free die-casting aluminum alloy provided by the invention is high in yield strength and obvious in weight reduction effect.

The invention discloses a method for improving creep resistance of a rare earth magnesium alloy, which comprises the following steps: S1, casting an ingot blank according to the mass percent of each component (0-6% of Y element, 1-3% of Nd element, 0.1-0.5% of Zr element and the balance of Mg element) in the rare earth magnesium alloy; s2, the ingot blank is subjected to solution treatment; s3, the material obtained after solution treatment is subjected to rolling deformation, the rolling deformation temperature ranges from 450 DEG C to 520 DEG C, the reduction rate ranges from 15% to 25%, and the roller linear speed ranges from 2 mm / s to 200 mm / s; and S4, the rolled and deformed material is subjected to aging treatment, the aging treatment temperature ranges from 180 DEG C to 260 DEG C, and the aging treatment time ranges from 5 h to 70 h. According to the method disclosed by the invention, an originally harmful and unavoidable precipitation-free zone formed along a grain boundary is converted into a precipitation-free zone which is beneficial to creep resistance and is uniformly distributed along an intragranular deformation zone, and the creep resistance is remarkably improved.

The invention provides a 7xxx series aluminum alloy plate strip for anodic oxidation with a high recovery ratio and a preparation method of the 7xxx series aluminum alloy plate strip. The 7xxx series aluminum alloy plate strip comprises the following elements of 0.06%-0.12% of Si element, 0.10%-0.25% of Fe element, 4.5%-5.5% of Zn element, 2.0%-3.0% of Mg element, 1.2%-2.0% of Cu element, 0.05%-0.15% of Mn element, 0.10%-0.15% of Er element, 0.10%-0.12% of Zr element, 0%-0.03% of Ti element and the balance aluminum element. The aluminum alloy plate strip is prepared through the steps of reclaimed material grading pretreatment, low-liquid-level semi-continuous casting, multi-stage homogenizing heat treatment, hot rolling, cold rolling, solid solution, pre-stretching, two-stage aging and the like. Through joint optimization of material components and the process, the finished plate strip has excellent mechanical performance, an oxidation film is uniform in color and luster, and salt mist resistance, friction resistance and the like are achieved.

The invention relates to the technical field of alloy stabilization, in particular to a method for enabling Mg element components of a 6-series alloy to be more stable, which comprises the following steps: in a 6-series alloy smelting stage, adding cerium and lanthanum into a melt according to a ratio, reacting with the alloy to generate a magnesium hydroxide stable phase, adding zirconium in a smelting process stage, and carrying out heat treatment to obtain the 6-series alloy. Carrying out extrusion forming on the alloy with uniformly distributed magnesium, carrying out stepped aging treatment, carrying out heat preservation at 120 DEG C for 8 hours to promote eta'phase precipitation, raising the temperature to 180 DEG C, carrying out heat preservation for 4 hours, and carrying out comprehensive performance detection on the alloy to ensure that the magnesium element is stable and the performance of the alloy reaches the standard so as to obtain a high-quality alloy product. The method solves the problems that the strength is unstable due to segregation of the magnesium element in the 6-series alloy, the corrosion resistance is reduced due to oxidation loss, the thermal responsiveness is reduced after T6 aging due to recrystallization abnormal diffusion (the hardness improvement amplitude is small), and the magnesium element stability and the alloy comprehensive performance optimization are difficult to realize by the existing process.

The application discloses a vacuum die-casting motor rotor casting aluminum alloy and a preparation method thereof. According to mass percentage, the vacuum die-casting motor rotor casting aluminum alloy comprises the following components: 3.0-6.5% of Ni elements, 0.3-1.0% of Fe elements, 0.2-0.4% of Mg elements, 0.02-0.1% of B elements, 0.1-0.6% of Ce elements, and the rest is Al, and the rest is impurity elements; wherein, the content of a single impurity element is less than 0.03%, and the total content of the impurity elements is less than 0.2%.

The present application relates to a kind of high-strength steel of anti-fatigue and crack arrest and its preparation method, it relates to metal material technical field, it is by the following chemical components by mass percentage composition: C:0.029-0.079%, Si:0.09-0.29%, Mn:1.41-1.69%, Nb:0.019-0.029%, Zr:0.0041-0.0199%, Mg:0.0014-0.0199%, the rest is Fe and inevitable impurity;Zr element and Mg element mass percentage also simultaneously satisfy formula: 0.0041%<Zr+Mg<0.0199%, and Zr / Mg=1-3.The high-strength steel plate of the present application adopts low-carbon, low-silicon, middle-manganese inexpensive chemical composition design, does not contain Cr, Ni, Cu and other valuable metal elements, substantially reduces material cost;The present application does not use traditional Al deoxidation technology, instead is Si-Mn initial deoxidation, Zr-Mg final composite deoxidation, forms small, dispersed and uniform composite oxysulfide, substantially improves plasticity and toughness, significantly improves anti-fatigue performance, is suitable for the high-strength steel of anti-fatigue performance requirement high offshore wind power equipment equipment.

The invention discloses a creep-resistant magnesium alloy with high elasticity modulus and high damping and a preparation method thereof, and the creep-resistant magnesium alloy with high elasticity modulus and high damping comprises the following components in percentage by mass: 1.2%-3.5% of Zn element, 2.5%-12% of Gd element, 0.5%-6% of Yb element, 0.15%-1.2% of Ni element, 0.3%-0.8% of Mn element, 0-0.5% of Cu element, 0.1%-5% of HRE element and the balance of Mg element. The HRE element is one or more of a Dy element, a Sm element and a Tb element, and the mixing enthalpy delta H of the creep-resistant magnesium alloy with the high elastic modulus and the high damping is-1.1 kJ / mol to-0.2 kJ / mol. The creep-resistant magnesium alloy with high elastic modulus and high damping is suitable for the fields of aerospace, precise instruments, transportation, 3C electronics and the like, and has remarkable technical and economic values.

The invention belongs to the technical field of preparation of thermoelectric semiconductor materials, and provides a method for synthesizing an Mg3 (Bi, Sb) 2-based material through ball milling in order to solve the problems that in the process of synthesizing a magnesium-based material through a ball milling method, the preparation time is long, and components are not uniform due to material cold welding caking, and the like, and the method comprises the steps that high-purity Bi particles, high-purity Sb particles and high-purity Mg chips are weighed in a glove box under the inert atmosphere; secondly, in a glove box, Bi particles and Sb particles are placed in a ball milling tank, ball milling balls with different diameters are added, and then pre-ball milling is conducted under the inert atmosphere; the preparation method comprises the following steps: pre-ball-milling Bi and Sb powder, adding Mg chips under the protection of an inert atmosphere after pre-ball-milling, fully mixing the ball-milled Bi and Sb powder with the Mg chips, and then ball-milling in the inert atmosphere to obtain the Mg3 (Bi, Sb) 2-based material. By changing the feeding sequence and optimizing the feeding particle size, the specific surface area of the powder is increased, the reaction speed of the powder and the Mg element is increased, and the phenomena of adhesion of the material and the tank wall and cold welding agglomeration are prevented, so that the material synthesis efficiency and the component uniformity are improved.

The invention provides a high-performance Al-Si-Cu-Mg alloy based on in-situ synthesis and a preparation method thereof, and belongs to the technical field of metal materials. AlSi10Mg and an AA-2024 alloy are subjected to ball milling and mixing according to the mass ratio of (3-5): (5-7), and the Al-Si-Cu-Mg alloy is obtained. The Al-Si-Cu-Mg alloy is prepared from, by mass, 4.5%-7.0% of Si, 1.3%-2.4% of Cu, 0.6%-1.1% of Mg and the balance Al, and the content of inevitable impurities is smaller than or equal to 0.1%. And the Al-Si-Cu-Mg alloy is subjected to fusion forming through a laser powder bed, and aging treatment is carried out at 160-200 DEG C for 0.2-8 h, so that the high-performance Al-Si-Cu-Mg alloy is obtained. According to the obtained high-performance Al-Si-Cu-Mg alloy, the density reaches 99.0%-99.6%, cracks are avoided, fine crystal grains are evenly distributed (smaller than or equal to 17 microns), intracrystalline cellular structures are fine (smaller than or equal to 0.57 microns), nanometer strengthening phases are separated out in a dispersed mode (the L phase (needle-shaped metastable phase containing Al, Si, Cu and Mg) is smaller than or equal to 10 nm, and the beta ''-Mg2Si is smaller than or equal to 50 nm). The method is simplified in process, suitable for near-net forming of complex components and high in material utilization rate. And meanwhile, under the condition that the high ductility is kept, high strength is still obtained, the yield strength of the alloy is larger than or equal to 362 MPa, and the tensile strength is larger than or equal to 519 MPa.

The invention relates to an aluminum alloy plate for an attenuation-resistant ultrathin tank cover material, which comprises the following elements in percentage by mass: 0.07-0.15% of Si element, 0.07-0.15% of Al element, 0.07-0.15% of Al element, 0.07-0.15% of Al element and the balance of aluminum element. 0.15 to 0.3 percent of Fe element; 0.07%-0.15% of a Cu element; 0.3 to 0.5 percent of Mn element; 4.75%-4.95% of an Mg element; 0.01%-0.03% of a Ti element; 0.02 to 0.10 percent of Cr element; 0.01%-0.20% of a Zn element; the total content of the inevitable impurities is smaller than or equal to 0.15%; the sum of the mass of the Mn element and the mass of the Cr element in the aluminum alloy plate for the tank cover material is 0.40-0.55%. After the 0.200-0.208 mm ultra-thin 202 series two-piece can easy-open cover prepared from the aluminum alloy is subjected to 90 DEG C / 40 min water boiling aging attenuation, the pressure resistance is larger than or equal to 700 KPa, and the attenuation amplitude is smaller than or equal to 30 KPa.

The application discloses a 7-series aluminum alloy material and a preparation method thereof, and belongs to the field of aluminum alloy preparation. On the basis of optimizing the composition of the 7-series aluminum alloy, the proportion of the components and the process are properly adjusted, so that the tensile strength, yield strength and elongation can be guaranteed to meet the use requirements, and the corrosion resistance can be further improved. The addition of Zn elements and Mg elements can significantly improve the strength and hardness of the 7-series aluminum alloy. The proper proportion of Cu or Cr can reduce residual phases (T phase-Al2Mg3Zn3 phase, AlZnMgCu phase or AlZnMgCr), but the residual phases gradually disappear after solid solution treatment, the alloying elements can be solid-solved in the matrix, the AlFe phase is reduced, and the corrosion sites are reduced. In combination with the synergistic effect of the Mn element and the V-containing refiner, the crystal phase of the 7-series aluminum alloy is refined, the mechanical properties of the 7-series aluminum alloy are significantly improved, and the corrosion resistance of the 7-series aluminum alloy is obviously improved.

The invention discloses a high-strength, high-modulus, light and low-cost magnesium-based multi-component alloy material based on magnesium-containing ternary second phase regulation and control, the magnesium-based multi-component alloy material is Mg-Al-Zn-Cu-Ca alloy, and according to atomic percent, the Mg element accounts for 70%-90%; 4%-18% of Al element; the content of Zn element is 4.5%-7%; the content of the Cu element is 3.5%-6%; 0.5%-2% of Ca element; wherein the magnesium-based multi-component alloy material has a phase structure of alpha-Mg, MgAl < 0.93 > Cu < 1.07 > and Mg32 (Al, Zn) < 49 >; compared with the prior art, on the basis of the Mg-Al-Zn-Cu-Ca alloy and the multi-component alloy design concept, the selective precipitation of a second phase can be realized by reasonably regulating and controlling the content of low-cost Al, Zn, Cu, Ca and other alloy elements and further combining a proper heat treatment process, so that the main precipitated phase is a magnesium-containing ternary high-modulus phase; and further, the elasticity modulus and the mechanical property of the whole alloy are optimized.

The application provides an aluminum alloy plate and a preparation method thereof. The preparation method comprises the following steps: after ingredients of the aluminum alloy plate are proportioned, melting, casting, integrated treatment of soaking and heating, hot rolling and cold rolling are sequentially performed to obtain a cold-rolled coil; the ingredients of the aluminum alloy plate comprise the following components in percentage by mass: 0.6-1.3% of Si element, 0.5-1.1% of Cu element, 0.6-1.2% of Mg element, 0.25% of Cr element, 0.7% of Zn element, 0.2% of Ti element, 0.2% of Zr element and the balance of Al element; the cold-rolled coil is sequentially subjected to solid solution, quenching (multi-stage cooling), straightening and pre-aging to obtain a first finished coil; and the first finished coil is subjected to differential temperature heating artificial aging treatment to obtain the aluminum alloy plate. The production efficiency of the above preparation method is high, and the comprehensive performance of the obtained aluminum alloy plate is good.

The invention discloses a high-strength, high-modulus, high-hardness, light and low-cost magnesium-based multi-component alloy material which is Mg-Al-Zn-Cu-Ca alloy, and the magnesium-based multi-component alloy material comprises the following components in percentage by atomic percent: 70-85% of Mg element, 5-10% of Zn element, 5-10% of Ca element, and the balance of Mg element. 4%-5% of Al element; the Zn element accounts for 9%-16%; 5%-6% of Cu element; the content of Ca element is 0.5%-1.5%; wherein the magnesium-based multi-component alloy material has a phase structure of alpha-Mg, Mg (Al, Zn) 0.93 Cu1.07, Mg32 (Al, Zn) 49, and MgZn2 or MgZn2-Mg (Al, Zn) 0.93 Cu1.07 eutectic crystals, and the magnesium-based multi-component alloy material has a phase structure of alpha-Mg, Mg (Al, Zn) 0.93 Cu1.07 eutectic crystals and a phase structure of Mg (Al, Zn) 0.93 Cu1.07 eutectic crystals. Compared with the prior art, on the basis of the Mg-Al-Zn-Cu-Ca alloy and the multi-component alloy design concept, the selective precipitation of a second phase can be realized by reasonably regulating and controlling the content of low-cost Al, Zn, Cu, Ca and other alloy elements and further combining a proper heat treatment process, so that the main precipitated phase is a magnesium-containing ternary high-modulus phase; and further, the elasticity modulus and the mechanical property of the whole alloy are optimized.

The invention provides a heat-treatment-free aluminum alloy and a preparation method thereof. The heat treatment-free aluminum alloy comprises the following elements in percentage by mass: 5.7-6.2% of Mg element; 2.3 to 2.9 percent of Si element; 1.9%-2.3% of a Zn element; 0.5 to 1.0 percent of Mn element; the total content of the inevitable impurities is smaller than or equal to 0.15%, and the balance is the element Al; the mass content of the MgZn2 phase in the heat treatment-free aluminum alloy is 3.20 to 5.04 percent; the mass content of an Al6Mn phase in the heat treatment-free aluminum alloy is 0.11 to 0.32 percent; the tensile strength of the heat-treatment-free aluminum alloy ranges from 345 MPa to 385 MPa, and the yield strength ranges from 230 MPa to 265 MPa. The aluminum alloy is simple in element composition, the element types and content of the heat-treatment-free aluminum alloy are controlled within the range, and the strength and the casting performance can be both considered.

This invention relates to the field of metallic materials technology, and in particular to an Al-Mg-Zn-Mn alloy, its preparation method, and alloy parts. The Al-Mg-Zn-Mn alloy, by mass percentage, comprises: Mg 3.5%–8%, Zn 0.1%–2%, Mn 0.5%–1.5%, Ti ≤0.02%, with the remainder being Al and unavoidable impurities. This invention introduces appropriate amounts of Mg, Zn, and Mn into the alloy. Furthermore, through heat treatment, the synergistic effect of the T-phase substitution mechanism at grain boundaries and the induction of Mg element aggregation and precipitation within the grains by Al6Mn as a pre-existing compound particle of the T-phase, the content of the T-phase precipitate at grain boundaries is reduced, thus decreasing the continuous precipitation of the T-phase at grain boundaries and improving the overall performance and corrosion resistance of the alloy.

The invention provides a 7xxx series aluminum alloy wire and a preparation method thereof, and an aluminum alloy workpiece and a preparation method thereof. The 7xxx series aluminum alloy wire is prepared from the following elements in percentage by mass: 7.0 to 9.0 percent of Zn element, 1.5 to 2.5 percent of Mg element, 0.5 to 1.5 percent of Cu element, 0.05 to 0.35 percent of Sc element, 0.05 to 0.25 percent of Zr element, less than or equal to 0.04 percent of Ti element, less than or equal to 0.15 percent of Fe element, less than or equal to 0.10 percent of Si element, less than or equal to 0.15 percent of inevitable impurities and the balance of Al element, the total mass content of the Sc element and the Zr element is 0.20-0.45%. The 7xxx series aluminum alloy wire is high in strength and not prone to cracking after being subjected to electric arc additive manufacturing and heat treatment, and the requirement for the mechanical property of aluminum alloy in the fields of aerospace and the like can be better met.

The application provides a brazing process of an aluminum alloy material for brazing. The material of a runner plate used in the brazing process is an aluminum rare earth material, which comprises, in percentage by mass, 7.0-9.0% of a rare earth metal element RE, 0.4-0.6% of an Fe element, 0.6-1.2% of an Mn element, 0.3-0.5% of a Cr element, 0.02-0.15% of an Mg element, 0.1-0.2% of a Ti element, 0.02-0.2% of a V element, 0.02-0.1% of a B element, ≤0.1% of an Si element, ≤0.01% of a Cu element, the balance of an Al element and inevitable impurities, and ≤0.05% of a single impurity element. After brazing by the brazing process, the weld is full and has high strength, and the brazing process is suitable for brazing of runner plates with various complex structures.

The invention discloses a low-cost high-toughness aluminum-silicon die-casting alloy and a preparation method thereof, and belongs to the technical field of light alloy materials. The alloy comprises the following components in percentage by mass: 7.0%-10.0% of Si, 0.8%-1.5% of Zn, 0.0%-0.5% of Mg, 0.0%-0.6% of Mn, 0.0%-0.2% of Ti, less than 0.2% of Fe and the balance of Al and inevitable impurities. The core of the invention is that Zn is used as a modificator to replace traditional Sr, eutectic silicon is effectively converted into a fibrous form, and the problems of deterioration decline, porosity increase and poisoning reaction caused by Sr deterioration are avoided. On the basis, Mg element is added to further refine the eutectic silicon structure, and the Mg element is combined with Zn to form a nano precipitated phase reinforced matrix. The alloy has excellent mechanical properties without heat treatment in a die-casting state, the yield strength is 130-160 MPa, the tensile strength is 260-300 MPa, the ductility is 10-16%, meanwhile, the alloy has excellent casting fluidity and heat crack resistance, the cost is low, and the alloy is particularly suitable for integrated die-casting forming of large structural parts of automobiles.

The invention relates to an ultra-fine grain aluminum magnesium alloy and a preparation method and application thereof, the ultra-fine grain aluminum magnesium alloy provided by the invention comprises the following chemical components: 4.0-6.0 wt% of Mg element, and the balance of Al and inevitable impurities; the grain size of the aluminum magnesium alloy ranges from 100 nm to 1000 nm. And an Mg element grain boundary segregation network is arranged at the grain boundary of the aluminum-magnesium alloy. According to the ultra-fine grain aluminum-magnesium alloy provided by the invention, while the strength of the aluminum alloy is guaranteed, through low-temperature aging treatment, a grain boundary structure is precisely regulated and controlled, segregation of Mg elements in a grain boundary area is induced, a stable three-dimensional discontinuous grain boundary segregation network is constructed, and the grain boundary segregation network can effectively reduce grain boundary energy and inhibit grain growth; and therefore, the structure thermal stability of the ultra-fine grain aluminum alloy is remarkably improved.

The invention provides an aluminum alloy for a zip-top can cover and a preparation method of the aluminum alloy. The aluminum alloy for the ring-pull can cover comprises the following elements in percentage by mass: 0.2-0.6% of Si element; 0.2 to 0.6 percent of Fe element; 0.2%-0.4% of a Cu element; 0.8 to 1.0 percent of Mn element; 1.1 to 1.4 percent of Mg element; 0.01%-0.03% of a Ti element; less than or equal to 0.03% of Ni element; less than or equal to 0.03% of Cr element; zn element < = 0.1%; the ratio of the total mass of the Fe element and the Mn element to the mass of the Si element is (2.5-5): 1; the mass of the Cu element is 2 times that of the Mg element, the sum of the mass of the Mn element and the mass of the Mg element is 2.6-2.9%, and the balance is the Al element; the mass content of the AlFeMnSi phase in the aluminum alloy for the ring-pull can cover ranges from 2.5% to 4.5%. The zip-top can cover prepared from the aluminum alloy is easy to recycle and regenerate.

The invention relates to an X7R type multilayer ceramic capacitor dielectric material and a preparation method thereof. The X7R type multilayer ceramic capacitor dielectric material is composed of a main component and auxiliary components, wherein the main component is a compound which is represented by a general formula ABO3 and has a perovskite type crystal structure, the first auxiliary component is at least one of Nb2O5 or MoO3, the second auxiliary component is an oxide of a rare earth element Re, the third auxiliary component is an oxide of Mg, and the fourth auxiliary component is an oxide of Si; relative to 1mol of ABO3 main component, the total addition amount a of Nb or Mo element is more than 0 and less than or equal to 0.1% mol, the addition amount b of Re element is more than or equal to 1.2 and less than or equal to 3.0% mol, the addition amount c of Mg element is more than or equal to 1.5 and less than or equal to 3.0% mol, and the addition amount d of Si element is more than or equal to 0.8 and less than or equal to 1.2% mol; a, b, c and d are located in a range surrounded by specific points in a ternary phase diagram formed by a + b, c and d.

The application provides a magnesium alloy and a preparation method thereof, a magnesium product and a preparation method thereof. According to the mass percentage of the magnesium alloy, the magnesium alloy comprises the following components: 4-5% of Al, 1-4% of Ca, 1-4% of Y, 0.1-0.3% of Nd, 0.1-0.3% of Mn, and the balance of inevitable impurities and Mg elements. The magnesium alloy satisfies the following condition: 0.70A+1.18D>0.50E+0.01G+0.07I. The magnesium alloy provided by the application is designed by multi-element alloying and the proportion of each element is controlled, so that the micro-galvanic effect in the alloy and the macro-galvanic corrosion tendency when the alloy contacts with dissimilar metals are significantly reduced, and meanwhile, good die casting process performance is maintained.

The invention belongs to the technical field of metal and nonmetal heterogeneous welding, and particularly relates to active brazing filler metal and a preparation method and application thereof.The active brazing filler metal comprises, by mass, 10%-45% of Mg element and the balance metal elements similar to metal to be welded and inevitable impurities; wherein the metal element similar to the metal to be welded comprises at least one of Al element and Sn element. The active brazing filler metal provided by the invention is magnesium-containing active brazing filler metal, is relatively high in activity, can be applied to heterogeneous welding of metal materials and non-metal materials, does not need to be pressurized, realizes welding of parts in complex shapes, and forms a good welding interface.

The invention discloses a low-thermal-expansion aluminum-silicon alloy and a preparation method thereof. The alloy comprises the following components in percentage by weight: 19.0-21.0 wt% of Si, 2-4.5 wt% of Cu, less than or equal to 0.4 wt% of Mg, 0.05-0.20 wt% of Ti, 0.1-0.2 wt% of Fe, 0.65-0.75 wt% of Mn, 0.01-0.1 wt% of Zr, 0.05-0.15 wt% of Sn, less than or equal to 0.01 wt% of other impurity elements in total, and the balance of Al. The preparation method comprises the steps of two-time sequential smelting, refining, degassing and deslagging, heat preservation and casting. Through the specific component design, the solid solution strengthening and phase change effects of the elements such as Cu and Mg are utilized, and the grain refinement effect of the elements such as Ti and Zr is cooperated, so that the good casting performance of the alloy is guaranteed, meanwhile, the thermal expansion coefficient is remarkably reduced, and the hardness and the tensile strength are improved. The method is suitable for structural members such as precise instruments and electronic product shells with high requirements on size thermal stability.

The invention provides an aluminum alloy and a preparation method thereof. The aluminum alloy comprises the following elements in percentage by mass: 0.4-0.6% of Mg element, 0.3-0.5% of Si element, 0.1-0.2% of Cu element, less than or equal to 0.15% of inevitable impurities and the balance of Al element, wherein the mass content of an Mg2Si phase in the aluminum alloy is 0.25 to 0.61 percent; the mass content of the Q phase in the aluminum alloy is 0.1-0.87%; the microhardness of the aluminum alloy ranges from 80 HV to 97 HV, and the conductivity of the aluminum alloy ranges from 58 IACS% to 60 IACS%. The aluminum alloy is simple in component, high strength and high conductivity can be considered, it is guaranteed that the conductivity is improved and the strength is not reduced after the aluminum alloy is subjected to aging treatment for a long time, and therefore the requirements of the new energy automobile light weight and the fast charging technology for the high-strength and high-conductivity aluminum material are met.

The invention discloses a high-heat-resistance magnesium alloy material and a preparation method thereof. The high-heat-resistance magnesium alloy material comprises 13-33% of rare earth elements; 0.2 to 1.0 percent of Zr element; impurity element < = 0.1%; and the balance of Mg element. Wherein the rare earth elements comprise two or more of Gd, Tb, Dy, Er, Lu and Tm, and contain Zr element; the impurity elements comprise Al, Cu, Fe, Ni and Si elements. The mass percent of each element is as follows: 3.0%-20% of Gd, 3.0%-20% of Tb, 3.0%-25% of Dy, 3.0%-28% of Er, 3.0%-30% of Lu and 3.0%-25% of Tm. 0.2 to 1.0 percent of Zr; al < = 0.02%, Cu < = 0.05%, Fe < = 0.05%, Ni < = 0.02% and Si < = 0.05%. The preparation method comprises alloy casting and heat treatment. After heat treatment, the room-temperature tensile strength of the high-heat-resistance magnesium alloy prepared through the method exceeds 370 MPa, and the percentage elongation after fracture is not lower than 3.0%; the strength of the alloy at the temperature of 250 DEG C or below is equivalent to the room-temperature strength, and the percentage elongation after fracture is slightly increased; and under the condition of 250 DEG C to 350 DEG C, relatively high strength is still maintained.

This invention discloses a high-manganese-content Al-Cu alloy composition and its heat treatment process for La and Ce alloying in metal mold casting. The designed alloy composition contains Mn and Mg elements, and alloying is achieved through La or Ce elements, which can refine α-Al grains, fully utilize the role of Mn, reduce segregation and suppress hot cracking tendency, and improve the microstructure uniformity of alloy ingots or castings. The designed as-cast alloy, after solution treatment and graded aging treatment, yields a final sample with a tensile strength of not less than 552 MPa and an elongation of not less than 7.2%. This invention differs from refining α-Al grains by adding refining agents or inoculants to promote nucleation of particles in the aluminum melt. Instead, it achieves grain refinement through composition design and under general solidification technology conditions, simplifying the melting process and casting process.