CN109439984B

CN109439984B - Preparation method of primary titanium carbide and amorphous phase co-reinforced magnesium-based composite material

Info

Publication number: CN109439984B
Application number: CN201811091941.5A
Authority: CN
Inventors: 彭建洪; 杨永潇; 毛多鹭; 李海琴; 李海宾; 韩精卫; 许珂琳; 周德华
Original assignee: Qinghai Nationalities University
Current assignee: Qinghai Nationalities University
Priority date: 2018-09-19
Filing date: 2018-09-19
Publication date: 2021-02-12
Anticipated expiration: 2038-09-19
Also published as: CN109439984A

Abstract

The invention discloses a primary micro/nano-scale titanium carbide and amorphous alloy co-strengthened magnesium alloy composite material and a preparation method thereof. The main steps are: ball milling titanium powder and graphite powder in proportion to obtain primary titanium carbide (TiCp) alloy Powder; mix magnesium powder or aluminum powder or titanium powder with other alloy elements in proportion to obtain magnesium-based/aluminum-based/titanium-based amorphous alloy powder; add TiCp alloy powder to amorphous alloy powder in proportion The mixed powder of TiCp and amorphous alloy is obtained by high-energy ball milling, and then the mixed powder is added to the magnesium alloy powder according to a certain proportion, and then alcohol is added, and the ultrasonic-assisted method is used for mechanical stirring, and the mixture is uniformly mixed and then dried; The dried composite powder is compacted at high pressure to obtain a dense composite block blank, and then hot-pressed and sintered at a low temperature; the composite block obtained by sintering is hot-extruded, and finally a high-strength and high-toughness primary micro/nano titanium carbide is obtained Co-strengthening magnesium alloy composites with amorphous alloys.

Description

Preparation method of primary titanium carbide and amorphous phase co-reinforced magnesium-based composite material

Technical Field

The invention relates to a light metal composite material, in particular to a hard carbide and amorphous alloy co-reinforced magnesium alloy composite material and a preparation method thereof.

Background

The magnesium alloy material has the characteristics of low density, high specific strength, high specific stiffness, good damping performance, good thermal conductivity, easy recycling and the like, and is widely applied to the fields of aviation, aerospace, vehicles, 3C electronic products and the like. However, since most magnesium alloys have a Hexagonal Close Packed (HCP) crystal structure, the HCP structure has less independent sliding systems, resulting in a magnesium alloy having lower room temperature ductility and toughness, and in addition, the mechanical strength and creep resistance of the magnesium alloy are also lower, which limits the wide application of the magnesium alloy material.

According to the strengthening mechanism, the micro-nano-scale particles with high hardness and high modulus are compounded with the fine-grained magnesium alloy material, so that the comprehensive mechanical property of the magnesium alloy material can be obviously improved. At present, in the literature reports of research on magnesium-based composite materials at home and abroad, the reinforcements commonly used mainly include silicon carbide, oxides (such as alumina and silica), boron carbide, titanium boride, graphene, whiskers/fibers, carbon nanotubes and the like, and the preparation methods mainly include a stirring casting method, an extrusion casting method, a powder metallurgy method, a mechanical alloying method, a pressureless infiltration method, a plasma sintering method, friction stir welding and the like. Chinese patent (CN107523727A) discloses that a silicon carbide reinforced magnesium-based composite material with excellent mechanical properties (the maximum tensile strength is 305MPa, and the elongation reaches 8.25%) is prepared by an extrusion casting method. Chinese patent (CN201710138404.0) discloses a method for preparing a nano titanium carbide particle reinforced magnesium-based composite material, which comprises the steps of adding a prefabricated body into a liquid magnesium alloy, synchronously applying mechanical stirring under the action of ultrasonic vibration to a magnesium alloy melt which is heated to a temperature of above 70 ℃ and is doped with the nano titanium carbide particle prefabricated body, effectively solving the problem of uniform distribution of nano titanium carbide particles, realizing uniform distribution of the added nano titanium carbide particles, ensuring that the maximum tensile strength of the added nano titanium carbide particles reaches 345MPa, and simultaneously ensuring that the composite material has good plastic toughness (the elongation of the composite material reaches 18%). Chinese patent (application No. 201710900751.2) discloses a mixed phase reinforced magnesium-based composite material and a preparation method thereof, which mainly comprises the following process steps: pretreating magnesium alloy powder, nano diamond particles and magnesium borate whiskers to prepare mixed powder, mixing and ball-milling to obtain ball-milled mixed powder, and then carrying out vacuum hot-pressing to form a blank and hot-extrusion treatment. The friction wear and the tensile-compression symmetry of the mixed-phase reinforced magnesium-based composite material prepared by the method are remarkably improved, and the comprehensive mechanical properties are also remarkably improved (the tensile/compression yield strengths are 390MPa and 433MPa respectively, the highest tensile/compression strengths are 418MPa and 480MPa respectively, and the tensile/compression strain rates are 6.2% and 10.1% respectively).

At present, no report is found on the research of in-situ synthesis of micro-nano carbide and amorphous alloy particles for co-strengthening the magnesium-based composite material at home and abroad. Chinese patent (CN101368242A) discloses an amorphous reinforced magnesium-based composite material and a preparation process thereof, wherein the material comprises amorphous particles Ni_xM_yT_z(M represents one or two of Zr and Nb, T represents at least one of Ta, Ti, Hf, Ti, Si, Pd, P, Sn, Co, Mo, B, Cr and Al; x is more than or equal to 30 and less than or equal to 70, y is more than or equal to 3 and less than or equal to 50, z is more than or equal to 0 and less than or equal to 35; a is more than or equal to 80 and less than or equal to 100, B is more than or equal to 0 and less than or equal to 18, c is more than or equal to 0 and less than or equal to 5, and d is_aAl_bQ_cR_d(a + B + c + d is 100 weight percent, a is more than or equal to 80 and less than or equal to 100, B is more than or equal to 0 and less than or equal to 18, c is more than or equal to 0 and less than or equal to 5, d is more than or equal to 0 and less than or equal to 3, Q represents one or two of Mn and Zn, and R represents at least one of Ce, Zr, Cu, Ni, Si, Fe, B and Gd). The main process of the invention comprises the following steps: uniformly mixing magnesium alloy particles and amorphous alloy particles, performing cold pressing at a cold pressing pressure of 30-250MPa, and then sintering in a hot-pressing sintering furnace at a hot-pressing pressure of 5-60MPa and a sintering temperature of 500-700 ℃ for 30-180 min. The strength and toughness indexes of the amorphous reinforced magnesium-based composite material obtained by the invention are not ideal (the yield strength is 145MPa at most, the tensile strength is 263MPa at the same time, and the elongation is 4.3%), and the possible reasons are that the grain size of a matrix structure is larger (the toughness of the matrix structure is poor) due to the adoption of higher sintering temperature, and in addition, the phase interface in the deformation process is easy to damage due to poor bonding performance of the amorphous phase and the matrix phase interface, so that cracks are generated and rapidly expanded, and the composite material is brittle.

Disclosure of Invention

The main ideas of the invention are as follows: native micro/nano TiC with high specific surface area, high activity and high hardness prepared by mechanical alloying method in-situ synthesis_pAnd light metal-based amorphous alloy particles with high crystallization temperature and high hardness, and then the WC particles are mixed with the amorphous alloy particles to carry out high-energy ball milling (to large-size TiC)_pThe particle part is embedded into the large-size amorphous alloy particles), and TiC is stirred by an ultrasonic-assisted mechanical stirring method_pGranules,Fully and uniformly mixing the amorphous alloy particles and the magnesium alloy powder, then densifying the composite powder under high pressure, and finally obtaining the high-strength high-toughness magnesium alloy composite material with a special three-phase coexisting structure by utilizing low-temperature sintering and hot extrusion processes. The main technical innovation of the invention is as follows: (1) forming a special three-phase coexistence structure, namely TiC with larger size in the composite material_pThe particles are simultaneously embedded in large-size amorphous alloy particles and a magnesium alloy matrix phase, the special structure can prevent the amorphous alloy phase from rotating along with matrix grains in the deformation process of the composite material, simultaneously, the amorphous phase has the function of preventing dislocation movement, and a phase interface with excellent mechanical property cannot be damaged under the action of larger shear stress, so that the integral strength of the composite material is greatly improved; (2) and fine TiC_pAnd the amorphous alloy particles can be dispersed in the superfine crystal magnesium alloy matrix, and can play a good role in dispersion strengthening.

In order to solve the technical problems, the technical scheme adopted by the invention is as follows:

step 1, mixing titanium powder and graphite powder in proportion, and performing high-energy ball milling for a period of time to obtain high-activity and high-specific-surface-area native TiC_pGranular powder;

step 2, mixing light metal magnesium powder or aluminum powder or titanium powder with other alloy elements according to a certain proportion, and performing high-energy ball milling for a period of time to obtain magnesium-based or aluminum-based or titanium-based amorphous alloy particle powder with high activity and high crystallization temperature;

step 3, TiC obtained in the step 1_pAdding the particle powder into the amorphous alloy particle powder obtained in the step 2 according to a certain proportion, and performing high-energy ball milling to obtain TiC_pAnd amorphous alloy mixed powder;

step 4, TiC obtained in step 3_pAdding the amorphous alloy mixed powder into magnesium alloy powder according to a certain proportion, adding a certain amount of alcohol, mechanically stirring in an ultrasonic-assisted mode to obtain uniformly mixed slurry, then putting the slurry into a vacuum oven for drying, and then obtaining composite powder;

step 5, placing the composite powder obtained in the step 4 in a mould, and performing high-pressure compaction by using a cold isostatic press or a four-column hydraulic press to obtain a compact composite block blank;

step 6, placing the compact composite block blank obtained in the step 5 into a vacuum hot-pressing sintering furnace for low-temperature hot-pressing sintering to obtain a high-density hot-pressing composite block material;

step 7, carrying out hot extrusion on the block composite material obtained in the step 6 at a high extrusion ratio to finally obtain the high-strength and high-toughness primary micro-nano/meter TiC_pAnd the amorphous alloy is used for co-strengthening the magnesium alloy composite material bar.

Further, in the step 1, the molar ratio of the titanium powder to the graphite powder is 1: 1, the mixture is subjected to high-energy ball milling, and Ti and C elements react in situ by utilizing high ball milling energy to synthesize native TiC with high specific surface area and high activity_p(according to the difference of ball milling energy and ball milling time, the degree of in-situ chemical reaction is different, and the range of the obtained p is 0.85-1). the ball milling time is 40-80 h, the ball-material ratio is 10: 1-20: 1, and the rotating speed is 300-600 r/min.

Further, in the step 2, magnesium powder or aluminum powder or titanium powder and other alloy elements (such as one or more of Cu, Ni, Si, Y, Fe, Ca, Zn, Nd, B, etc.) are mixed according to a certain proportion, and then the mixture is subjected to high-energy ball milling to obtain magnesium-based or aluminum-based or titanium-based amorphous alloy particle powder (the breaking strength of which is required to be not lower than 800MPa, the crystallization temperature is required to be not lower than 350 ℃), the ball milling time is 40-100 h, the ball-to-material ratio is 10: 1-50: 1, and the rotating speed is 300-600 r/min.

Further, in the step 3, TiC_pThe mixing ratio of the particles to the amorphous alloy particles is 1: 6-1: 20, and TiC is obtained after high-energy ball milling_pThe ball milling time of the mixed powder of the particles and the amorphous alloy particles is 20-40 h, the ball-material ratio is 10: 1-20: 1, and the rotating speed is 300-600 r/min. The purpose of this step is to make the TiC partially larger in size_pThe particles are embedded in the amorphous alloy particles and form a special three-phase coexisting structure, namely large TiC, in the final bulk composite material_pThe particles are embedded in the amorphous alloy phase and the matrix phase at the same time and are changed in the composite materialThe amorphous phase is prevented from rotating in the forming process, so that the overall strength of the composite material is greatly improved; and fine TiC_pAnd the amorphous alloy particles are dispersed in the magnesium alloy matrix to play a role in dispersion strengthening.

Further, in the step 4, TiC added to the magnesium alloy powder_pThe particles and the amorphous alloy particles respectively account for 0.25-5% and 5-30% of the total mass of the mixed powder, and the balance is magnesium alloy powder; the adding amount of the alcohol is only required to ensure that the slurry has enough fluidity during stirring; the ultrasonic power is 100-200 Hz, the rotating speed of the blades is 300-1000 rpm, and the stirring time is 30-60 min.

Furthermore, in the step 4, the grade of the magnesium alloy powder can be one of Mg-Al series, Mg-Zn series, Mg-Mn series, Mg-RE series or Mg-Zn-RE-Zr series.

Further, in the step 4, the slurry which is uniformly stirred and mixed is dried in vacuum, the vacuum degree is less than 100Pa, the drying temperature is 80 ℃, and the drying time is 24 hours.

Further, in the step 5, the mold is a stainless steel mold, the pressure of the cold isostatic pressing or the four-column hydraulic pressure is 300-600MPa, and the pressure maintaining time is 10-30 min.

Further, in the step 6, in order to prevent the crystal grain growth of the magnesium alloy matrix material in the sintering process, the vacuum hot pressing process adopts low-temperature sintering, the sintering temperature range is 300-350 ℃, the pressure is 50-100 MPa, and the pressure maintaining time is 20min-1 h. The purpose of low temperature sintering is: (1) the magnesium-based amorphous alloy is prevented from being crystallized and transformed in the compounding process, so that the strengthening effect of the amorphous alloy on the finally prepared composite material is ensured; (2) the magnesium alloy matrix of the final composite material is kept to be an ultrafine grain structure, so that the final composite material is ensured to have good plastic toughness.

Further, in the step 7, the temperature of hot extrusion is 280-300 ℃, the extrusion ratio is 25: 1, and the extrusion rate is 0.05-0.2 mm/s. The purpose of high extrusion specific heat extrusion is: further densifying the composite and possibly refining the matrix structure.

Further, the preparation method of the invention can also comprise a common magnesium alloy heat treatment method: t1-partial solution treatment and natural aging; t2-post-casting annealing; t3-solid solution + cold working; t4-solution treatment; t5-artificial aging; t6-solution treatment and artificial aging; t7-solution treatment and stabilization treatment; t8-polishing treatment, cold working and artificial aging.

Drawings

FIG. 1 is a process flow diagram of the preparation of the primary micro/nano-scale titanium carbide and amorphous alloy co-reinforced magnesium alloy composite material

Fig. 2 is a stress-strain graph of examples 1, 2, and 3.

Detailed Description

Example 1:

a method for preparing a native micro/nano titanium carbide and titanium-based amorphous alloy co-reinforced magnesium alloy composite material comprises the following steps:

step 1, weighing 8g of titanium powder and 2g of graphite powder, putting the titanium powder and the graphite powder into a 250ml ball milling tank, and then putting 100g of ball milling steel balls. Vacuumizing a ball milling tank, introducing argon (with the purity of 99.9 vol.%) into the ball milling tank from an air inlet at one end, putting the ball milling tank into a ball mill, wherein the ball milling time is 60 hours, and the rotating speed of the ball mill is 500rpm, so that the micro/nano TiC is obtained_pAnd (3) granular powder.

Step 2, according to Ti₅₀Zr₁₅Cu₁₅Ni₅V₅Be₁₀The molar ratio of elements in the molecular formula of the alloy compound is that titanium powder, zirconium powder, copper powder, nickel powder, vanadium powder and beryllium powder (the total mass of the powder is 25g) are weighed and put into a 500ml ball milling tank, and then 250g ball milling steel balls are put into the ball milling tank. Vacuumizing a ball milling tank, introducing argon (with the purity of 99.9v 01%) into the ball milling tank from an air inlet at one end, putting the ball milling tank into a ball mill, wherein the ball milling time is 100 hours, and the rotating speed of the ball mill is 500rpm, so that Ti is obtained₅₀Zr₁₅Cu₁₅Ni₅V₅Be₁₀Amorphous alloy particle powder.

Step 3, then TiC obtained in the step 1_pGranular powder (5g) was added to the Ti obtained in step 2₅₀Zr₁₅Cu₁₅Ni₅V₅Be₁₀Ball milling is continuously carried out on the amorphous alloy particle powder (the ball milling time is 20 hours, and the rotating speed of the ball mill is 500rpm), and then TiC is obtained_pParticles and Ti₅₀Zr₁₅Cu₁₅Ni₅V₅Be₁₀Mixed powder of amorphous alloy particles.

Step 4, taking out the mixed powder obtained in the step 3, weighing 75g of AZ91 magnesium alloy powder, putting the powder into a 500ml beaker, adding 200ml of alcohol into the beaker, and then carrying out ultrasonic-assisted mechanical stirring (the ultrasonic power is 100Hz, the blade rotation speed is 1000rpm, and the stirring time is 60 min); after stirring, putting the uniformly mixed slurry into a vacuum drying oven for drying (the vacuum degree is 50Pa, the drying temperature is 80 ℃, and the drying time is 24 h).

Step 5, placing the dried composite powder obtained in the step 4 into a stainless steel mold, and performing high-pressure compaction (the pressure is 500MPa, and the pressure maintaining time is 10-30min) by using a four-column hydraulic press to obtain a compact composite block blank;

step 6, putting the compact composite block blank obtained in the step 5 into a vacuum hot-pressing sintering furnace for hot-pressing sintering (the sintering pressure is 100MPa, the temperature is 300 ℃, and the pressure maintaining time is 1 hour), so as to obtain a high-density hot-pressing composite block material;

and 7, carrying out hot extrusion on the block composite material obtained in the step 6 at a high extrusion ratio (the extrusion temperature is 300 ℃, the extrusion ratio is 25: 1, and the extrusion rate is 0.05mm/s), and finally obtaining the magnesium alloy composite material bar.

The primary micro-nano/nano TiC finally obtained by the embodiment_p(5%) and Ti₅₀Zr₁₅Cu₁₅Ni₅V₅Be₁₀Machining an amorphous alloy (25%) co-reinforced magnesium alloy composite bar to obtain a standard tensile test sample, and then performing a tensile test on a universal mechanical testing machine, wherein the test result is as follows (see fig. 2): the yield strength of the composite material is 514MPa, the maximum tensile strength is 546MPa, and the maximum elongation is 6.2%.

Example 2:

a method for preparing a native micro/nano-scale titanium carbide and aluminum-based amorphous alloy co-reinforced magnesium alloy composite material comprises the following steps:

Step 2, according to Al₆₅Cu₂₀Ti₁₀Y₅The molar ratio of elements in the molecular formula of the alloy compound is that aluminum, copper powder, titanium powder and yttrium powder (the total mass of the powder is 15g) are weighed and put into a 500ml ball milling tank, and then 300g ball milling steel balls are put into the ball milling tank. Vacuumizing a ball milling tank, introducing argon (with the purity of 99.9 vol.%) into the ball milling tank from an air inlet at one end, putting the ball milling tank into a ball mill, wherein the ball milling time is 80 hours, and the rotating speed of the ball mill is 500rpm, so that Al is obtained₆₅Cu₂₀Ti₁₀Y₅Amorphous alloy particle powder.

Step 3, then TiC obtained in the step 1_pAdding granular powder (2g) to the Al obtained in step 2₆₅Cu₂₀Ti₁₀Y₅Ball milling is continuously carried out on the amorphous alloy particle powder (the ball milling time is 20 hours, and the rotating speed of the ball mill is 500rpm), and then TiC is obtained_pParticles and Al₆₅Cu₂₀Ti₁₀Y₅Mixed powder of amorphous alloy particles.

Step 4, taking out the mixed powder obtained in the step 3, weighing 83g of AZ91 magnesium alloy powder, putting the powder into a 500ml beaker, adding 200ml of alcohol into the beaker, and then carrying out ultrasonic-assisted mechanical stirring (the ultrasonic power is 100Hz, the blade rotation speed is 600rpm, and the stirring time is 60 min); after stirring, putting the uniformly mixed slurry into a vacuum drying oven for drying (the vacuum degree is 50Pa, the drying temperature is 80 ℃, and the drying time is 24 h).

and 7, carrying out hot extrusion on the block composite material obtained in the step 6 at a high extrusion ratio (the extrusion temperature is 300 ℃, the extrusion ratio is 25: 1, and the extrusion rate is 0.1mm/s), and finally obtaining the magnesium alloy composite material bar.

The primary micro-nano/nano TiC finally obtained by the embodiment_p(2%) and Al₆₅Cu₂₀Ti₁₀Y₅The amorphous alloy (15%) co-reinforced magnesium alloy composite material bar is machined to obtain a standard tensile test sample, and then a tensile test is carried out on a universal mechanical testing machine, wherein the test result is as follows (see figure 2): the yield strength of the composite material is 416MPa, the maximum tensile strength is 448MPa, and the maximum elongation is 6.7%.

Example 3:

a method for preparing a primary micro/nano titanium carbide and magnesium-based amorphous alloy co-reinforced magnesium alloy composite material comprises the following steps:

And 2, weighing 7.30g of magnesium powder and 17.70g of nickel powder, putting into a 500ml ball milling tank, and then putting into 250g of ball milling steel balls. Vacuumizing a ball milling tank, introducing argon (with the purity of 99.9 vol.%) into the ball milling tank from an air inlet at one end, filling the ball milling tank into a ball mill, wherein the ball milling time is 80 hours, and the rotating speed of the ball mill is 500rpm, so that Mg is obtained₅₀Ni₅₀Amorphous alloy particle powder.

Step 3, weighing the TiC obtained in the step 1_p0.25g of granular powder, and weighing the Mg obtained in the step 2₅₀Ni₅₀10g of amorphous alloy particle powder, namely 89.75g of AZ91 magnesium alloy powder, putting the three powder into a 500ml beaker, adding 200ml of alcohol into the beaker, and then carrying out ultrasonic-assisted mechanical stirring (the ultrasonic power is 100Hz, the blade rotation speed is 600rpm, and the stirring time is 60 min); after stirring, putting the uniformly mixed slurry into a vacuum drying oven for drying (the vacuum degree is 50Pa, the drying temperature is 80 ℃, and the drying time is 24 h).

and 7, carrying out hot extrusion on the block composite material obtained in the step 6 at a high extrusion ratio (the extrusion temperature is 300 ℃, the extrusion ratio is 25: 1, and the extrusion rate is 0.15mm/s), and finally obtaining the magnesium alloy composite material bar.

The primary micro-nano/nano TiC finally obtained by the embodiment_p(0.25%) and Mg₅₀Ni₅₀The amorphous alloy (10%) co-reinforced magnesium alloy composite material bar is machined to obtain a standard tensile test sample, and then a tensile test is carried out on a universal mechanical testing machine, wherein the test result is as follows (see figure 2): the yield strength of the composite material is 338MPa, the maximum tensile strength is 418MPa, and the maximum elongation is 9.6%.

Claims

1. a preparation method of primary micro/nano-level titanium carbide and amorphous alloy co-strengthening magnesium alloy composite material, is characterized in that comprising the following steps:

Step 1. Mix the titanium powder and the graphite powder in proportion, and obtain the primary titanium carbide TiC _p particles with high activity and high specific surface area after high-energy ball milling for a period of time;

Step 2. Mix light metal magnesium powder or aluminum powder or titanium powder with some other alloy elements in a certain proportion, and after high-energy ball milling for a period of time, obtain magnesium-based or aluminum-based or titanium-based amorphous alloy particles with high activity and high crystallization temperature powder;

Step 3, adding the TiC _p particle powder obtained in step 1 to the amorphous alloy particle powder obtained in step 2 in a certain proportion, and obtaining a mixed powder of TiC _p and amorphous alloy after high-energy ball milling;

Step 4. Add the TiC _p and amorphous alloy mixed powder obtained in step 3 into the magnesium alloy powder in a certain proportion, and then add a certain amount of alcohol, and perform mechanical stirring with ultrasonic assistance to obtain a uniformly mixed slurry, and then mix the powder. The slurry is dried in a vacuum oven to obtain a composite powder;

Step 5. Place the composite powder obtained in Step 4 in a mold, and perform high-pressure compaction with a cold isostatic press or a four-column hydraulic press to obtain a dense composite block blank;

Step 6, putting the dense composite block blank obtained in step 5 into a vacuum hot pressing sintering furnace for low temperature hot pressing sintering to obtain a highly dense hot pressing composite block;

Step 7, performing hot extrusion of the bulk composite material obtained in step 6 with a high extrusion ratio, and finally obtaining a high-strength and high-toughness primary micro/nano-scale titanium carbide and amorphous alloy co-strengthened magnesium alloy composite material;

Step 8, heat-treating the magnesium alloy composite material obtained in step 7;

In the step 1, the molar ratio of titanium powder and graphite powder is 1:1, and after high-energy ball milling for a period of time, primary TiC _p with high activity and high specific surface area is obtained. Differently, the obtained particle powder with p in the range of 0.85-1, the ball milling time is 40-80h, the ball-to-material ratio is 10:1-20:1, and the rotation speed is 300-600r/min; in the step 2, the light metal Magnesium powder or aluminum powder or titanium powder and one or more of other alloying elements Cu, Ni, Si, Y, Fe, Ca, Zn, Nd, B, mixed in a certain proportion, and obtained after high-energy ball milling For magnesium-based or aluminum-based or titanium-based amorphous alloy particles, the fracture strength should not be lower than 800MPa, the crystallization temperature should not be lower than 350℃, the ball milling time should be 40~100h, and the ball to material ratio should be 10:1~50 : 1, the speed is 300-600r/min;

In the step 3, the mixing ratio of TiC _p particles and amorphous alloy particles is 1:6 to 1:20. After high-energy ball milling, a mixed powder of TiC _p particles and amorphous alloy particles is obtained, and the ball milling time is 20 to 40 hours. , the ratio of ball to material is 10:1~20:1, and the speed is 300-600r/min;

In the step 4, the TiC _p particles and amorphous alloy particles added to the magnesium alloy powder account for 0.25-5% and 5-30% of the total mass of the mixed powder, respectively, and the rest are magnesium alloy powder; The amount of alcohol added should only ensure that the slurry has sufficient fluidity during stirring; the ultrasonic power during ultrasonic-assisted mechanical stirring is 100-200Hz, the blade speed is 300-1000rpm, and the stirring time is 30-60min;

In the step 6, in order to prevent the grain growth of the magnesium alloy matrix material during the sintering process, the vacuum hot pressing process adopts low temperature sintering, the sintering temperature range is 300-350°C, the pressure is 50-100MPa, and the pressure holding time is 20min -1h;

In the step 7, the temperature of the hot extrusion is 280-300° C., the extrusion ratio is 25:1, and the extrusion rate is 0.05-0.2 mm/s.

2. preparation method according to claim 1, is characterized in that: in described step 4, the trade mark of magnesium alloy powder is one in Mg-Al system, Mg-Zn system, Mg-Mn system, Mg-RE system kind.

3. The preparation method according to claim 1, characterized in that: in the step 4, the uniformly stirred and mixed slurry is vacuum-dried, the degree of vacuum is less than 100Pa, the temperature of the drying material is 80°C, and the drying time is 24h .

4. preparation method according to claim 1 is characterized in that: in described step 5, used mould is stainless steel mould, and the pressure of cold isostatic pressing or four-column hydraulic pressure is 300-600MPa, and the holding time is 10-30min .

5. The preparation method according to claim 1, characterized in that: in the step 8, appropriate heat treatment is performed on the prepared magnesium alloy composite material, that is, some common magnesium alloy heat treatment methods are adopted: T1-partial solution treatment + natural aging; T2- annealing after casting; T3- solution + cold working; T4 - solution treatment; T5 - artificial aging; T6 - solution treatment + artificial aging; T7 - solution treatment + stabilization treatment; T8 - solid solution Solution treatment + cold working + artificial aging.