CN112126826A

CN112126826A - Alloy material flange and preparation method thereof

Info

Publication number: CN112126826A
Application number: CN202011014882.9A
Authority: CN
Inventors: 费爱华; 费新海; 邵德金
Original assignee: Wuxi Xingda Petrochemical Fittings Co ltd
Current assignee: Wuxi Xingda Petrochemical Fittings Co ltd
Priority date: 2020-09-24
Filing date: 2020-09-24
Publication date: 2020-12-25

Abstract

The invention provides an alloy material flange which comprises the following chemical components in percentage by weight: si 5-10%, Cu 2.5-4.5%, C0.5-0.7%, Ni 0.1-0.4%, Fe1.5-5%, V0.1-0.3%, B0.3-0.5%, La0.01-0.05%, Ce0.01-0.03%, Nb0.02-0.04%, Os0.03-0.05%, and balancing aluminum. The alloy material flange prepared by the invention has good high temperature resistance, corrosion resistance, abrasion resistance and high strength, and can be applied to various occasions and has wide application range.

Description

Alloy material flange and preparation method thereof

Technical Field

The invention relates to the technical field of alloy materials, in particular to an alloy material flange and a preparation method thereof.

Background

In order to fully exert the series of excellent characteristics of aluminum alloy represented by 'light', the aluminum alloy has to be developed greatly in the aspect of 'strong', and meanwhile, the use field of the aluminum alloy can be greatly expanded without unacceptable increment of manufacturing cost. This requires that a breakthrough must be made in the design of new aluminum alloy materials.

In view of the method of material preparation, since the material characteristics are contributed by the combination of functional microscopic phases bearing the characteristics, obtaining a good combination of functional phases, such as high strength, high melting point, high plasticity, high hardness, corrosion resistance, etc., is the final result sought by various preparation methods. The mixed smelting and casting crystallization of the formulation elements is the main decisive link for forming the material phase-molecule combination structure by the casting method, in the casting process, the intermetallic compound molecule phase of solid solution crystal grains and grain boundaries determines the crystalline combination (submicron particles: about 10-300 μm in dimension) of the alloy, the subsequent heat treatment or cold work hardening adjusts and perfects the fine structure (micron particles: about 1-30 μm in dimension) under the crystalline combination frame and even the microscopic fine structure (sub-nanometer or sub-micron particles: about 10 nm-less than 1 μm in dimension), the degree and range of the adjustment and perfection are determined by the phase combination given by the alloy phase diagram area where the alloy chemical components are located in the known technology and the traditional concept, but the alloy phase diagram does not give out the influence generated by the addition and the elimination of other trace elements, and less instructive in predicting the effect of adding and excluding other trace elements on the physical phase. The improvement of the melt structure, such as the covering of a protective film, the addition of a slagging agent, a refining agent or a modifier, degassing, deslagging and purification and the like by using the theory and the method of alloy solution chemistry as reference is an important technical means for improving the alloy crystalline combination, the microstructure and even the microscopic microstructure, but the means are obtained by groping and accumulating in the process of preparing the alloy, and are often regarded as a part of a preparation process rather than a component design.

In engineering application, the size and state of the aluminum alloy solid solution grains and the size and shape of the intermetallic compound distributed in the grain boundary have decisive influence on the mechanical properties of the alloy. Irregular crystals such as coarse plane crystals, dendrites, columnar crystals and the like and coarse brittle intermetallic compounds distributed in grain boundaries can completely offset the contribution of fine structures and fine structures of the alloy to the toughness of a matrix, and because the growth rule followed by the coarse grains is a growth mode of nucleation on a mold wall of a casting cavity and unidirectional extension from outside to inside of liquid, the defects of component segregation, coarse and unidirectional crystallization and nonuniform macroscopic properties of the alloy are caused, and the defects become the root sources of common defects of the alloy, such as pinholes, pores, shrinkage cavities, shrinkage porosity, segregation, coarse solid solutions, high-hardness compounds, cracks and the like. At present, the best effect of the conventional modification means and grain refinement means adopted, such as adding Al-Ti-B or Al-Ti-C intermediate alloy, can only refine the average grain size to 120-150 microns, and the form of dendrite is not fundamentally transformed, which is an important bottleneck problem for improving the mechanical property of the alloy. For aluminum alloys, only grain refinement and rounding are available, as a way to simultaneously improve strength and toughness; the adjustment of the heat treatment process can only optimize one aspect of strength or toughness in a state that the crystalline structure is already determined. Therefore, how to further refine and round the average grain size of the alloy is a constant goal pursued by the industry.

According to the theory of alloy strengthening, the strength of the alloy is generated by the interference or dislocation slip in the material being hindered by mass points, and the stronger the hindrance, the stronger the strength of the material. The result of particle impeding behavior interacting with interfaces or dislocation slips in the material is two types: one is that when the strength and hardness of mass point is not high enough, dislocation will slip continuously through mass point, the other is that the strength of mass point is high, dislocation can not slip continuously by bypassing mass point, and a ring of dislocation ring is left around mass point. The magnitude of the contribution of both results to the material strength is evident: the bypass particles contribute more to the strength of the material than the cut particles; cutting through the particles provides better elongation of the material, while bypassing the particles provides higher yield and tensile strength of the material due to the strengthening effect of the dislocation loops.

The flange filter is small equipment for removing solid matter from liquid, and can protect compressor, pump, other equipment and instrument from normal operation, stabilize technological process and ensure safety. In addition, the flange filter made of aluminum alloy materials in the market is small in specification (the diameter is less than 150 mm), most of the materials are aluminum silicon (Al-Si), the aluminum silicon system is good in formability, but low in strength and hardness, cannot meet the requirements in engineering application with thick pipe diameter, large flow and large pressure, and is prone to safety problems such as leakage and breakage.

Disclosure of Invention

The invention aims to provide an alloy material flange and a preparation method thereof, which have good high-temperature resistance, corrosion resistance, wear resistance and high strength, and the prepared flange can be applied to various occasions and has a wide application range.

The technical scheme of the invention is realized as follows:

the invention provides an alloy material flange which comprises the following chemical components in percentage by weight: si 5-10%, Cu 2.5-4.5%, C0.5-0.7%, Ni 0.1-0.4%, Fe1.5-5%, V0.1-0.3%, B0.3-0.5%, La0.01-0.05%, Ce0.01-0.03%, Nb0.02-0.04%, Os 0.03-0.05%, modified epoxy soybean oil lubricant 0.01-0.05%, and the balance of aluminum;

the modified epoxidized soybean oil is prepared by the following method:

adding 100 parts by weight of dehydrated epoxidized soybean oil into a reactor, heating to 45-55 ℃ under the protection of nitrogen, adding 0.1-0.5 part by weight of composite coupling agent, stirring for reaction for 1-3h, adding 5-10 parts by weight of di-n-butyl phosphoramide, heating to 55-70 ℃, continuing to react for 1-2h, cooling to 30-35 ℃, discharging, filtering, and grinding to below 1000 meshes to obtain the modified epoxidized soybean oil.

As a further improvement of the invention, the composite coupling agent is a mixture of a silane coupling agent with an epoxy group and a silane coupling agent with an amino group, and the mass ratio of the silane coupling agent with an epoxy group to the silane coupling agent with an amino group is 1: (1-3), wherein the silane coupling agent with an epoxy group is KH 560; the silane coupling agent with amino is selected from one or a mixture of KH550, KH602 and KH 792.

As a further improvement of the invention, the weight percentage of the chemical components are as follows: si 7-9%, Cu 3-4%, C0.55-0.65%, Ni0.2-0.3%, Fe 2-4%, V0.15-0.25%, B0.35-0.45%, La0.02-0.04%, Ce0.015-0.025%, Nb0.025-0.035%, Os0.035-0.045%, modified epoxy soybean oil lubricant 0.02-0.04%, and the balance of aluminum.

As a further improvement of the invention, the weight percentage of the chemical components are as follows: si 8%, Cu3.5%, C0.6%, Ni0.25%, Fe 3%, V0.2%, B0.3%, La0.03%, Ce0.025%, Nb0.03%, Os0.04%, modified epoxidized soybean oil lubricant 0.03%, and the balance of aluminum.

As a further improvement of the invention, the tensile strength of the alloy material flange is 557-625MPa, the thermal conductivity is 112-125W/m.K, and the thermal expansion coefficient is 15.5-16.2 × 10^-6/K。

The invention further provides a preparation method of the alloy material flange, which comprises the following steps:

s1, weighing raw material simple substances according to a proportion, adding the raw material simple substances into an induction furnace for heating, melting, refining and degassing, circularly flowing molten metal into a device through a leakage nozzle by adopting a supersonic gas atomization method, spraying supersonic gas to alloy liquid flow, cooling and solidifying to form fine powder to obtain mixed metal powder;

s2, sieving the mixed metal powder prepared in the step S1, mixing, primarily loading, compacting, loading into a special pure aluminum sheath, degassing in vacuum, welding the sheath, heating the sheath, preserving heat, and extruding on a hydraulic press to obtain an extruded material;

and S3, carrying out high-temperature oxygenation oxidation on the extruded material obtained in the step S2, and cooling to obtain a flange blank.

As a further improvement of the invention, in step S1, the supersonic gas is provided by a supersonic nozzle vortex tube, the flow rate is 50-300m3/h, the pressure is 1-1.5 atm, and the temperature is 120-150 ℃.

As a further improvement of the invention, in the step S2, the particle size of the screen is 100 meshes, the heating temperature of the sheath is 400-500 ℃, the heat preservation time is 1-2h, the extrusion ratio is 15-20, the extrusion speed is 0.5-1cm/min, and the extrusion cone angle is 90 degrees.

As a further improvement of the present invention, the conditions of the high temperature oxygenation in step S3: the oxidation temperature is 420-450 ℃, the oxidation time is 80-90h, and the oxygenation pressure is 0.5-1 MPa.

As a further improvement of the invention, the mean median diameter of the mixed metal powder is from 5 to 10 microns.

The invention has the following beneficial effects: the invention utilizes supersonic gas to spray alloy liquid flow to decompose the alloy liquid flow into fine molten drops, and the small molten drops are rapidly cooled and then solidified to form fine powder under the action of forced gas convection. The atomized powder preparation has the characteristics of relatively regular, fine and uniform powder particle shape and high powder yield. Meanwhile, analysis and comparison of various preparation technologies of the silicon-aluminum alloy show that the comprehensive performance of the material prepared by ball-milling pretreatment of the alloy powder is optimal; the invention adopts a high-temperature oxygenation process, after oxygenation, crystal grains in the material tissue grow, the material density is increased, the air tightness is improved, the thermal expansion coefficient of the material is slightly increased, the thermal conductivity of the material can be improved by oxidation, and the mechanical properties are improved in different ways;

the main technological parameters of the hot extrusion of the powder blank comprise extrusion force, extrusion temperature, extrusion speed and the like, and the phenomena of under burning and extrusion difficulty are avoided by adjusting appropriate parameters such as selection of critical temperature, tensile strength, yield strength and hardness value of the material to the best. The extrusion speed produces a change in the metal heat balance during the forming process. Selecting a proper extrusion speed to avoid the phenomenon that a better tissue only appears at the tail end of a product due to excessive heat dissipation; or because the contact time of the blank and the inner wall of the die is short, heat can not be transferred in time, heat insulation extrusion can be formed in a deformation area, the alloy temperature at an extrusion outlet is higher and higher, and the phenomena of cracking and the like on the surface of the material are caused. The extrusion ratio has larger influence on the mechanical property and the deformation uniformity of the material, and the proper extrusion ratio is adjusted to avoid serious nonuniformity of the mechanical property between the inner layer and the outer layer of the material, because the powder does not generate enough deformation and loose and porous tissues in the material cannot be tightly combined, so that the mechanical property of the material is reduced; or the inhomogeneity of the material properties is reduced, but the deformation resistance of the powder is increased correspondingly. At the same time, an inappropriate extrusion ratio also produces a significant thermal effect, which causes the actual deformation temperature of the powder to be too high, resulting in coarse matrix grains.

The alloy material for manufacturing the flange comprises Cu2.5-4.5% and Ni0.1-0.4%, wherein Cu and Ni play roles in oxidation resistance and high temperature resistance, has higher strength and oxidation resistance at the high temperature of 1000 ℃ of 700-; the steel contains 0.1-0.3% of V and 78-10% of Si5, can improve the capability of resisting various acid corrosion and stress corrosion, and simultaneously reduces the friction loss of a flange material and improves the wear resistance of the flange material; wherein, the content of B is 0.3 to 0.5 percent and the content of C is 0.5 to 0.7 percent, so that the alloy has better mechanical property, higher resistivity, lower temperature coefficient of resistivity and good corrosion resistance, and the oxidation resistance and the high-temperature strength of the alloy material are improved; rare earth elements La, Ce and Nb are added into the alloy material, so that the effects of refining, desulfurizing, neutralizing low-melting-point harmful impurities can be achieved, the processing performance of the alloy can be improved, the physical and chemical properties of the alloy can be improved to a great extent, and the room-temperature and high-temperature mechanical properties of the alloy can be improved;

the modified epoxidized soybean oil lubricant is added, the di-n-butyl phosphoramide is coupled with the epoxidized soybean oil, the lubricating oil has better lubricating property and abrasion resistance, the phosphorus-containing lubricating additive and the aluminum alloy generate a chemical reaction film due to a tribochemical reaction, so that the friction property of the aluminum alloy material can be obviously improved, the critical content of a stable surface film formed by the di-n-butyl phosphoramide and the aluminum alloy is lower, the performance difference of the formed surface film is smaller, the tribological property of the aluminum alloy can quickly enter a stable state, and the soybean oil has good lubricating property.

The alloy material flange prepared by the invention has good high temperature resistance, corrosion resistance, abrasion resistance and high strength, and can be applied to various occasions and has wide application range.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.

FIG. 1 is a metallographic photograph of a flange blank of an alloy material prepared in example 3 of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example 1

The raw materials comprise (by weight percentage chemical components) Si 5%, Cu2.5%, C0.5%, Ni0.1%, Fe1.5%, V0.1%, B0.3%, La0.01%, Ce0.01%, Nb0.02%, Os0.03%, modified epoxidized soybean oil lubricant 0.01%, and the balance of aluminum.

The modified epoxidized soybean oil is prepared by the following method:

adding 100g of dehydrated epoxidized soybean oil into a reactor, heating to 45 ℃ under the protection of nitrogen, adding 0.1g of composite coupling agent, stirring for reaction for 1h, adding 5g of di-n-butyl phosphoramide, heating to 55 ℃, continuing to react for 1h, cooling to 30 ℃, discharging, filtering, and grinding to below 1000 meshes to obtain the modified epoxidized soybean oil.

The method comprises the following steps:

s1, weighing the raw material simple substances according to a proportion, adding the raw material simple substances into an induction furnace for heating, melting, refining and degassing, and passing molten metal through a supersonic gas atomization methodIn the discharge spout circulation inflow device, supersonic gas (flow rate 50 m) generated by supersonic nozzle vortex tube is used³The alloy liquid flow is sprayed at the pressure of 1 atmosphere and the temperature of 120 ℃, and the mixed metal powder is obtained after being cooled and solidified into fine powder, wherein the average median diameter is 5.2 microns;

s2, passing the mixed metal powder prepared in the step S1 through a 100-mesh screen, mixing, primarily loading, compacting, loading into a special pure aluminum sheath, vacuum degassing, welding the sheath, heating the sheath at 400 ℃, keeping the temperature for 1h, extruding on a hydraulic press at an extrusion ratio of 15, an extrusion speed of 0.5cm/min and an extrusion cone angle of 90 degrees to obtain an extruded material;

s3, carrying out high-temperature oxygenation and oxidation on the extruded material obtained in the step S2, cooling to obtain a flange blank, wherein the oxidation temperature is 420 ℃, the oxidation time is 80 hours, and the oxygenation pressure is 0.5 MPa.

Example 2

The raw materials comprise the following chemical components in percentage by weight: si 10%, Cu4.5%, C0.7%, Ni0.4%, Fe 5%, V0.3%, B0.5%, La0.05%, Ce0.03%, Nb0.04%, Os0.05%, modified epoxidized soybean oil lubricant 0.05%, and the balance of aluminum.

The modified epoxidized soybean oil is prepared by the following method:

adding 100g of dehydrated epoxidized soybean oil into a reactor, heating to 55 ℃ under the protection of nitrogen, adding 0.5g of composite coupling agent, stirring for reaction for 3 hours, adding 10g of di-n-butyl phosphoramide, heating to 70 ℃, continuing to react for 2 hours, cooling to 35 ℃, discharging, filtering, and grinding to below 1000 meshes to obtain the modified epoxidized soybean oil.

The method comprises the following steps:

s1, weighing the raw material simple substances according to a proportion, adding the raw material simple substances into an induction furnace for heating, melting, refining and degassing, circularly flowing molten metal into a device through a leakage nozzle by adopting a supersonic gas atomization method, and generating supersonic gas (the flow is 300 m) by utilizing a supersonic nozzle vortex tube³The alloy liquid flow is sprayed at the pressure of 1.5 atmospheric pressure and the temperature of 150 ℃), and fine powder is formed after cooling and solidification to obtain mixed metal powder with the average median diameter of 9.7 microns;

s2, passing the mixed metal powder prepared in the step S1 through a 100-mesh screen, mixing, primarily loading, compacting, loading into a special pure aluminum sheath, vacuum degassing, welding the sheath, heating the sheath at 500 ℃, keeping the temperature for 2 hours, extruding on a hydraulic press at an extrusion ratio of 20, an extrusion speed of 1cm/min and an extrusion cone angle of 90 degrees to obtain an extruded material;

s3, carrying out high-temperature oxygenation and oxidation on the extruded material obtained in the step S2, cooling to obtain a flange blank, wherein the oxidation temperature is 450 ℃, the oxidation time is 90h, and the oxygenation pressure is 1 MPa.

Example 3

The raw materials comprise the following chemical components in percentage by weight: si 8%, Cu3.5%, C0.6%, Ni0.25%, Fe 3%, V0.2%, B0.3%, La0.03%, Ce0.025%, Nb0.03%, Os0.04%, modified epoxidized soybean oil lubricant 0.02%, and the balance of aluminum.

The modified epoxidized soybean oil is prepared by the following method:

adding 100g of dehydrated epoxidized soybean oil into a reactor, heating to 50 ℃ under the protection of nitrogen, adding 0.3g of composite coupling agent, stirring for reaction for 2 hours, adding 7g of di-n-butyl phosphoramide, heating to 62 ℃, continuing to react for 1.5 hours, cooling to 32 ℃, discharging, filtering, and grinding to below 1000 meshes to obtain the modified epoxidized soybean oil.

The method comprises the following steps:

s1, weighing the raw material simple substances according to a proportion, adding the raw material simple substances into an induction furnace for heating, melting, refining and degassing, circularly flowing molten metal into a device through a leakage nozzle by adopting a supersonic gas atomization method, and generating supersonic gas (the flow is 150 m) by utilizing a supersonic nozzle vortex tube³The alloy liquid flow is sprayed at the pressure of 1.2 atmospheric pressure and the temperature of 135 ℃, and the mixed metal powder is solidified into fine powder after being cooled to obtain mixed metal powder with the average median diameter of 7.5 microns;

s2, passing the mixed metal powder prepared in the step S1 through a 100-mesh screen, mixing, primarily loading, compacting, loading into a special pure aluminum sheath, vacuum degassing, welding the sheath, heating the sheath at 450 ℃, keeping the temperature for 1.5 hours, extruding on a hydraulic press, wherein the extrusion ratio is 17, the extrusion speed is 0.75cm/min, and the extrusion cone angle is 90 degrees to obtain an extruded material;

s3, carrying out high-temperature oxygenation oxidation on the extruded material obtained in the step S2, cooling to obtain a flange blank, wherein the oxidation temperature is 435 ℃, the oxidation time is 85h, and the oxygenation pressure is 0.75 MPa.

Fig. 1 is a metallographic photograph of the flange blank prepared in this example, in which after the material is oxidized by high-temperature oxygenation, silicon particles are coarsened, and Si particles are more in the structure, and local segregation of Si phase occurs. The solid diffusion of atoms is promoted due to long-time heating and heat preservation when the alloy material is in high-temperature oxygenation and oxidation and the material is in a high-temperature heating process, so that a matrix and Si phase crystal grains grow.

Example 4

The composition of the raw materials was different from that of example 3, and the other conditions were the same.

The raw materials comprise the following chemical components in percentage by weight: si 7%, Cu 3%, C0.55%, Ni0.2%, Fe 2%, V0.15%, B0.35%, La0.02%, Ce0.015%, Nb0.025%, Os0.035%, modified epoxidized soybean oil lubricant 0.04%, and the balance of aluminum.

Example 5

The raw materials comprise the following chemical components in percentage by weight: si 9%, Cu 4%, C0.65%, Ni0.3%, Fe 4%, V0.25%, B0.45%, La0.04%, Ce0.025%, Nb0.035%, Os0.045%, modified epoxidized soybean oil lubricant 0.03%, and the balance of aluminum.

Comparative example 1

Compared with example 3, Cu was not added, and other conditions were the same.

The raw materials comprise the following chemical components in percentage by weight: si 8%, C0.6%, Ni3.75%, Fe 3%, V0.2%, B0.3%, La0.03%, Ce0.025%, Nb0.03%, Os0.04%, modified epoxidized soybean oil lubricant 0.02%, and the balance of aluminum.

Comparative example 2

Compared with example 3, Ni was not added, and other conditions were the same.

The raw materials comprise the following chemical components in percentage by weight: si 8%, Cu3.75%, C0.6%, Fe 3%, V0.2%, B0.3%, La0.03%, Ce0.025%, Nb0.03%, Os0.04%, modified epoxidized soybean oil lubricant 0.02%, and the balance of aluminum.

Comparative example 3

In comparison with example 3, V was not added, and other conditions were the same.

The raw materials comprise the following chemical components in percentage by weight: 8.2 percent of Si, 3.5 percent of Cu3, 0.6 percent of C, 0.25 percent of Ni0.25 percent of Fe3 percent of B, 0.3 percent of La0.03 percent of La, 0.025 percent of Ce0.03 percent of Nb0.03 percent of Os0.04 percent of modified epoxidized soybean oil lubricant, and the balance of aluminum.

Comparative example 4

In comparison with example 3, Si was not added, and other conditions were the same.

The raw materials comprise the following chemical components in percentage by weight: cu3.5%, C0.6%, Ni0.25%, Fe 3%, V8.2%, B0.3%, La0.03%, Ce0.025%, Nb0.03%, Os0.04%, modified epoxidized soybean oil lubricant 0.02%, and the balance of aluminum.

Comparative example 5

In comparison with example 3, B was not added, and other conditions were the same.

The raw materials comprise the following chemical components in percentage by weight: si 8%, Cu3.5%, C0.9%, Ni0.25%, Fe 3%, V0.2%, La0.03%, Ce0.025%, Nb0.03%, Os0.04%, modified epoxidized soybean oil lubricant 0.02%, and the balance of aluminum.

Comparative example 6

In comparison with example 3, C was not added, and other conditions were the same.

The raw materials comprise the following chemical components in percentage by weight: si 8%, Cu3.5%, Ni0.25%, Fe 3%, V0.2%, B0.8%, La0.03%, Ce0.025%, Nb0.03%, Os0.04%, modified epoxidized soybean oil lubricant 0.02%, and the balance of aluminum.

Comparative example 7

The other conditions are the same as those in example 3 without going through step S3.

The method comprises the following steps:

s2, the mixed metal powder prepared in the step S1 is screened by a 100-mesh screen, mixed, initially loaded, compacted, loaded into a special pure aluminum sheath, subjected to vacuum degassing, welded and heated at 450 ℃, kept for 1.5 hours, extruded on a hydraulic press at an extrusion ratio of 17, an extrusion speed of 0.75cm/min and an extrusion cone angle of 90 degrees to obtain a flange blank.

Comparative example 8

Compared with example 3, the modified epoxidized soybean oil lubricant was replaced by epoxidized soybean oil under the same conditions.

The raw materials comprise the following chemical components in percentage by weight: si 8%, Cu3.5%, C0.6%, Ni0.25%, Fe 3%, V0.2%, B0.3%, La0.03%, Ce0.025%, Nb0.03%, Os0.04%, epoxidized soybean oil 0.02%, and the balance of aluminum.

Test example 1

The alloy material flanges prepared in examples 1-5 and comparative examples 1-8 of the present invention and commercially available flanges were subjected to mechanical property tests, and normal temperature and high temperature tensile tests were performed on an Instron5569 universal tensile testing machine at a tensile rate of 0.2 mm/min. The tensile sample size meets the national standard of GBT228-2002 tensile sample. The results are shown in Table 1.

TABLE 1

Group of	Tensile strength at 25 ℃ (MPa)	300 ℃ tensile Strength (MPa)
			Example 1	562	557
Example 2	573	565
			Example 3	625	618
Example 4	601	592
			Example 5	594	588
Comparative example 1	522	510
			Comparative example 2	514	507
Comparative example 3	545	532
			Comparative example 4	552	540
Comparative example 5	425	302
			Comparative example 6	457	311
Comparative example 7	424	410
			Comparative example 8	520	517
Commercially available flange material	322	275

As can be seen from the above table, the alloy material flange prepared by the embodiment of the invention has better normal-temperature and high-temperature mechanical properties.

Test example 2

The alloy material flanges prepared in the embodiments 1-5 and the comparative examples 1-8 of the invention and the commercially available flanges are subjected to a friction resistance test, and a high-temperature friction test is carried out on an MMU-5G material end surface high-temperature friction abrasion tester. The test method of pin-disc type sliding friction and abrasion is adopted in the test. Alloy sample size d 4mm x 15mm pin sample, 43mm diameter GCr15 steel for the grinding disc. The friction test is carried out under the condition of dry friction, the sample alloy is respectively worn for 5min at 4 different temperatures of 25 ℃, 100 ℃, 200 ℃ and 300 ℃, and the load is all 100N. Before formal friction, each sample is pre-ground on 800-mesh sand paper for 5min to improve the fit degree of the wear surface of the sample with a friction wheel. The samples were ultrasonically cleaned with acetone before abrasion and blown dry before measurement with an analytical balance with an accuracy of 0.01 mg. And describing the wear resistance of the material to be tested by adopting the friction mass loss.

The results are shown in tables 2 and 3.

TABLE 2

TABLE 3

As can be seen from the table, the alloy material flange prepared by the embodiment of the invention has better friction resistance.

Test example 3

The alloy material flanges prepared in the examples 1-5 and the comparative examples 1-8 of the invention and the commercially available flanges are subjected to performance tests, the density of the sample is tested by adopting a drainage method, and the minimum precision of the analytical balance is 0.1 mg; the gas tightness test was carried out on a He adsorption tester model HeLIOT306S produced in Japan. The results are shown in Table 4.

TABLE 4

Group of	Density (g/cm)³)	Airtightness (Pa. m)³·s^-1)
			Example 1	2.5212	5.9
Example 2	2.5134	6.2
			Example 3	2.5024	6.5
Example 4	2.5113	6.3
			Example 5	2.5104	6.1
Comparative example 1	2.4962	4.5
			Comparative example 2	2.4895	3.2
Comparative example 3	2.5014	5.7
			Comparative example 4	2.5112	5.3
Comparative example 5	2.4952	5.6
			Comparative example 6	2.5022	5.7
Comparative example 7	2.3221	3.2
			Comparative example 8	2.4214	6.0
Commercially available flange material	2.4592	5.2

As can be seen from the above table, the alloy material flange manufactured by the embodiment of the invention has good air tightness and moderate density.

Test example 4

The alloy material flanges prepared in the embodiments 1-5 and the comparative examples 1-8 of the invention and the commercially available flanges are subjected to thermal performance test, according to the national standard GB11108-89, the thermal diffusivity test is carried out on a JR-2 thermophysical property tester, the thermal diffusivity of a sample at normal temperature is measured by adopting a flash method, and then the thermal conductivity is obtained according to the relationship among the thermal conductivity, the thermal diffusivity, the density and the constant pressure specific heat capacity, and the formula is as follows:

λ＝100·α·ρ·C_ρ

wherein α is thermal diffusivity (cm)²S); ρ is the density (g/cm)³)；C_ρSpecific heat capacity at constant pressure (J. (g/K))

The thermal expansion coefficient test was performed on a japanese physical differential thermal analyzer.

The results are shown in Table 5.

TABLE 5

Group of	Coefficient of thermal conductivity (W/m. K)	Coefficient of thermal expansion (. times.10)^-6/K)
			Example 1	112	15.5
Example 2	117	15.6
			Example 3	125	16.2
Example 4	121	15.8
			Example 5	120	16.0
Comparative example 1	82	10.5
			Comparative example 2	89	9.8
Comparative example 3	102	13.2
			Comparative example 4	105	12.5
Comparative example 5	104	14.1
			Comparative example 6	101	13.7
Comparative example 7	78	12.5
			Comparative example 8	102	15.0
Commercially available flange material	99	10.2

As can be seen from the above table, the alloy material flange prepared by the embodiment of the invention has good thermal expansion coefficient and thermal conductivity.

Compared with the example 3, the comparative example 1 and the comparative example 2 have the advantages that the high temperature resistance performance is obviously reduced without adding Cu or Ni respectively, and the Cu and Ni are added, wherein the Cu and Ni play roles in oxidation resistance and high temperature resistance, have higher strength and oxidation resistance at the high temperature of 700-1300 ℃, and can be used for a long time even at the temperature of 1200-1300 ℃, and have the synergistic effect.

Compared with the embodiment 3, the wear resistance of the flange material is obviously reduced by adding V or Si in comparison with the embodiment 4, and the wear resistance of the flange material is improved by adding V and Si, so that the friction loss of the flange material is reduced, the wear resistance of the flange material is improved, and the V and Si have synergistic effect.

Compared with the embodiment 3, the comparative examples 5 and 6 have no addition of B or C respectively, all the performances of the alloy are reduced to some extent, including high temperature resistance and friction resistance, and the addition of B and C ensures that the alloy has better mechanical property, higher resistivity, lower resistivity temperature coefficient and good corrosion resistance, improves the oxidation resistance and high temperature resistance of the alloy material, and has synergistic effect.

Compared with the embodiment 3, the embodiment 7 does not adopt the high-temperature oxygenation process, after the embodiment 3 is oxygenated at high temperature, the grains in the material tissue grow up, the density of the material is increased, the air tightness is improved, the thermal expansion coefficient of the material is slightly increased, the thermal conductivity of the material can be improved by oxidation, and the mechanical property is improved in different ways.

Compared with the embodiment 3, the epoxidized soybean oil is adopted to replace the modified epoxidized soybean oil lubricant, the wear resistance of the modified epoxidized soybean oil lubricant is obviously reduced, the di-n-butyl phosphoramide is coupled with the epoxidized soybean oil, the modified epoxidized soybean oil lubricant has better lubricity and wear resistance, a phosphorus-containing lubricating additive and the aluminum alloy generate a chemical reaction film due to a tribochemical reaction, so that the friction performance of the aluminum alloy material can be obviously improved, the critical content of a stable surface film formed by the di-n-butyl phosphoramide and the aluminum alloy is lower, the performance difference of the formed surface film is smaller, the tribological performance of the aluminum alloy can quickly enter a stable state, and the soybean oil has good lubricating performance.

Compared with the prior art, the invention utilizes supersonic gas to spray alloy liquid flow to decompose the alloy liquid flow into fine molten drops, and the small molten drops are rapidly cooled and then solidified to form fine powder under the action of forced gas convection. The atomized powder preparation has the characteristics of relatively regular, fine and uniform powder particle shape and high powder yield. Meanwhile, analysis and comparison of various preparation technologies of the silicon-aluminum alloy show that the comprehensive performance of the material prepared by ball-milling pretreatment of the alloy powder is optimal; the invention adopts a high-temperature oxygenation process, after oxygenation, crystal grains in the material tissue grow, the material density is increased, the air tightness is improved, the material thermal expansion coefficient is slightly increased, the material thermal conductivity can be improved by oxidation, and the mechanical properties are improved in different ways;

The alloy material for manufacturing the flange comprises Cu2.5-4.5% and Ni0.1-0.4%, wherein Cu and Ni play roles in oxidation resistance and high temperature resistance, has higher strength and oxidation resistance at the high temperature of 1000 ℃ of 700-; the steel contains 0.1-0.3% of V and 78-10% of Si5, can improve the capability of resisting various acid corrosion and stress corrosion, and simultaneously reduces the friction loss of a flange material and improves the wear resistance of the flange material; the alloy contains 0.3-0.5% of B and 0.5-0.7% of C, so that the alloy has good mechanical property, high resistivity, low temperature coefficient of resistivity and good corrosion resistance, and the oxidation resistance and high-temperature resistance of the alloy material are improved.

Rare earth elements La, Ce and Nb are added into the alloy material, so that the effects of refining, desulfurizing, neutralizing low-melting-point harmful impurities can be achieved, the processing performance of the alloy can be improved, the physical and chemical properties of the alloy can be improved to a great extent, and the room-temperature and high-temperature mechanical properties of the alloy can be improved;

the modified epoxidized soybean oil lubricant is added, the di-n-butyl phosphoramide is coupled with the epoxidized soybean oil, so that the lubricating oil has better lubricating property and abrasion resistance, the phosphorus-containing lubricating additive and the aluminum alloy generate a chemical reaction film due to a tribochemical reaction, so that the friction property of the aluminum alloy material can be obviously improved, the critical content of a stable surface film formed by the di-n-butyl phosphoramide and the aluminum alloy is lower, and the difference of the properties of the formed surface film is smaller, so that the tribological property of the aluminum alloy can quickly enter a stable state, and the soybean oil has good lubricating property;

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.

Claims

1. The alloy material flange is characterized by comprising the following chemical components in percentage by weight: si 5-10%, Cu 2.5-4.5%, C0.5-0.7%, Ni 0.1-0.4%, Fe1.5-5%, V0.1-0.3%, B0.3-0.5%, La0.01-0.05%, Ce0.01-0.03%, Nb0.02-0.04%, Os 0.03-0.05%, modified epoxy soybean oil lubricant 0.01-0.05%, and the balance of aluminum;

the modified epoxidized soybean oil is prepared by the following method:

adding dehydrated epoxidized soybean oil into a reactor, heating to 45-55 ℃ under the protection of nitrogen, adding a composite coupling agent, stirring for reaction for 1-3h, adding di-n-butyl phosphoramide, heating to 55-70 ℃, continuing to react for 1-2h, cooling to 30-35 ℃, discharging, filtering, and grinding to below 1000 meshes to obtain the modified epoxidized soybean oil.

2. The alloy material flange according to claim 1, wherein the composite coupling agent is a mixture of a silane coupling agent with an epoxy group and a silane coupling agent with an amino group, and the mass ratio of the silane coupling agent with an epoxy group to the silane coupling agent with an amino group is 1: (1-3), wherein the silane coupling agent with an epoxy group is KH 560; the silane coupling agent with amino is selected from one or a mixture of KH550, KH602 and KH 792.

3. The alloy material flange according to claim 1, characterized in that the alloy material flange comprises the following chemical components in percentage by weight: si 7-9%, Cu 3-4%, C0.55-0.65%, Ni0.2-0.3%, Fe 2-4%, V0.15-0.25%, B0.35-0.45%, La0.02-0.04%, Ce0.015-0.025%, Nb0.025-0.035%, Os0.035-0.045%, modified epoxy soybean oil lubricant 0.02-0.04%, and the balance of aluminum.

4. The alloy material flange according to claim 3, characterized in that the alloy material flange comprises the following chemical components in percentage by weight: si 8%, Cu3.5%, C0.6%, Ni0.25%, Fe 3%, V0.2%, B0.3%, La0.03%, Ce0.025%, Nb0.03%, Os0.04%, modified epoxidized soybean oil lubricant 0.03%, and the balance of aluminum.

5. The alloy flange as claimed in claim 1, wherein the alloy flange has a tensile strength of 557-625MPa, a thermal conductivity of 112-125W/m.K, and a thermal expansion coefficient of 15.5-16.2X 10^-6/K。

6. A method for preparing a flange made of alloy material according to any one of claims 1 to 5, characterized by comprising the following steps:

7. The method as claimed in claim 6, wherein the supersonic gas is provided by a supersonic nozzle vortex tube in step S1, the flow rate is 50-300m3/h, the pressure is 1-1.5 atm, and the temperature is 120-150 ℃.

8. The method as claimed in claim 6, wherein the mesh size of the screen is 100 meshes in step S2, the heating temperature of the sheath is 400-500 ℃, the holding time is 1-2h, the extrusion ratio is 15-20, the extrusion speed is 0.5-1cm/min, and the extrusion cone angle is 90 °.

9. The method according to claim 6, wherein the conditions of the high temperature oxygenation in step S3: the oxidation temperature is 420-450 ℃, the oxidation time is 80-90h, and the oxygenation pressure is 0.5-1 MPa.

10. The method of claim 6, wherein the mixed metal powder has an average median diameter of 5 to 10 μm.