CN115415513B - Titanium alloy and ceramic reinforced phase ball milling powder mixing process optimization method based on uniformity - Google Patents

Abstract

The invention relates to an optimization method of a titanium alloy and ceramic reinforced phase ball milling powder mixing process based on uniformity, which comprises the steps of sampling composite powder of the ball milling powder mixing process, taking the whole uniformity M and the area uniformity alpha in the ball milling powder mixing process of the titanium alloy and ceramic reinforced phase composite powder, establishing a ball milling powder mixing uniformity model of the titanium alloy and ceramic reinforced phase composite powder, and taking the composite powder ball milling powder mixing uniformity model as a basis, so that the influence of process parameters on the uniformity of the ball milling powder mixing of the composite powder for preparing a reticular titanium-based composite material can be accurately described, thereby optimizing the preparation process parameters of the composite powder of the metal-based composite material, further obtaining uniformly distributed titanium alloy and ceramic reinforced phase composite powder, and facilitating industrial application; meanwhile, the optimization process can be applied to ball milling powder mixing processes of other alloy or ceramic reinforcing phases.

Description

Optimization method of ball milling powder mixing process based on uniformity of titanium alloy and ceramic reinforcement phase

Technical Field

The invention relates to the field of metal matrix composite materials, and in particular to a method for quantitatively optimizing a powder mixing process by using ball milling to improve the uniformity of the powder mixing.

Background Art

The cutting-edge science and technology field represented by aerospace has put forward higher requirements for the high reliability, low energy consumption and functional efficiency of equipment. The main load-bearing components made of high-performance lightweight metals can meet the requirements of reducing the structural weight of key components of high-end equipment and improving the service performance of equipment. Titanium-based composite materials made of titanium alloy and ceramic reinforcement phase can simultaneously give play to the advantages of high strength and toughness of titanium alloy and high heat resistance and strength of ceramic phase. Compared with traditional titanium alloy, ceramic-reinforced titanium-based composite materials have higher strength, modulus, wear resistance, heat resistance, high durability and service temperature, and can serve for a long time in complex and harsh environments.

During the manufacturing process of titanium-based composite materials, ceramic reinforcement phase powder is uniformly mixed with spherical titanium alloy particles, and the ceramic reinforcement phase powder is uniformly distributed on the surface of the spherical titanium alloy particles without destroying the shape of the spherical titanium alloy particles. A composite powder of titanium alloy and ceramic reinforcement phase uniformly distributed on the surface of the titanium alloy in a network can be obtained. The network titanium-based composite material prepared by this high-quality composite powder can significantly improve the plastic processability of the titanium-based composite material, and further improve the room temperature and high temperature mechanical properties of the ceramic reinforced titanium-based composite material. Reference 1 "Attar H, Bonisch M, Calin M, et al. Selective laser melting of in situ titanium-titaniumboride composites: Processing, microstructure and mechanical properties. ActaMaterialia, 2014, 76:13-22." discloses a ball milling mixing method for pure Ti and _TiB2 , and based on the qualitative analysis of the composite powder, the ball milling process parameters of the composite powder are optimized. Reference 2 "Yang Jianlei. Research on Hot Extrusion Process of _TiB2 /Ti-6Al-4V Composite Powder Encapsulation. Harbin: Master's Thesis of Harbin Institute of Technology, 2014." discloses a ball milling method for mixing Ti-6Al-4V and _TiB2 . The ball milling process parameters were optimized by qualitatively analyzing the uniformity of the composite powder, and a uniformly distributed composite powder was obtained. The composite powder qualitative analysis method used in the above reference cannot accurately describe the influence of the ball milling process parameters on the uniformity of the composite powder. Even for specific composite powders, a large amount of ball milling test data is still required, and the test results cannot be extended to the ball milling process of other alloys or ceramic reinforcement phases, which has the disadvantages of non-optimization, cost and time consumption.

Summary of the invention

The purpose of the present invention is to avoid the shortcomings of the prior art and provide a titanium alloy and ceramic reinforcement phase ball milling mixing process optimization method based on uniformity based on quantitative characterization of ball milling mixing uniformity and the influence of process parameters on the uniformity of ball milling mixing of titanium alloy and ceramic reinforcement phase composite powder, thereby obtaining the actual process parameters after the composite powder ball milling mixing is optimized.

To achieve the above object, the technical solution adopted by the present invention is: a method for optimizing the ball milling powder mixing process of titanium alloy and ceramic reinforcement phase based on uniformity, comprising the following steps:

Step 1: Take the composite powder of titanium alloy and ceramic reinforcement phase obtained under the ball milling mixing process parameters to be optimized, spread the composite powder on the conductive adhesive, randomly select at least 3 composite powder areas on the conductive adhesive, and take microscopic scanning photos in each area at two magnification ranges of 50-80 and 300-400;

Step 2, take the microscopic scanning photos in the range of 50 to 80 times described in step 1, and observe whether there is a distribution and aggregation phenomenon of 10 or more ceramic reinforcing phase powders gathered together within the range of the photo; the ceramic reinforcing phase powder in the composite powder is overall distributed and aggregated, that is, it is determined to be overall uneven, and the ceramic reinforcing phase powder in the composite powder does not appear to be distributed and aggregated, that is, it is determined to be overall uniform. After the overall uniformity is determined, take out the microscopic scanning photos of 300 to 400 times corresponding to the microscopic scanning photos of 50 to 80 times of the overall uniformity;

Step 3: Take the 300-400 times microscope scan obtained in step 2, and establish a ball milling mixing uniformity model of titanium alloy and ceramic reinforcement phase composite powder in the field of view of the microscope scan:

，

,

为所述复合粉末的区域均匀性；S ₁为游离的陶瓷增强相面积之和，单位为µm²；S ₂为未球磨混粉前的球形钛合金颗粒的面积之和，单位为µm²；n ₁为游离的陶瓷增强相的个数；n ₂为球形钛合金颗粒的个数；ρ ₁为陶瓷增强相密度，单位为g·cm^-3；ρ ₂为钛合金密度，单位为g·cm^-3；ω为陶瓷增强相的相对质量分数；In the formula,

is the regional uniformity of the composite powder; S1 _is the sum of the areas of the free ceramic reinforcement phase, in ^µm2 ; S2 is the sum of the areas of the spherical titanium alloy particles before ball milling , in µm2; n1 is the number of free ceramic reinforcement phases; n2 is the number of spherical titanium alloy particles; ρ1 ^is the _{density of the} ceramic reinforcement phase _, in g·cm ^-3 ; ρ2 is the density of the _titanium alloy, in g·cm ^-3 ; ω is the relative mass fraction of the ceramic reinforcement phase;

_The sum of the areas of the free ceramic reinforcement phase S1 refers to the difference between the sum of the areas of the free ceramic reinforcement phase powder and the titanium alloy particles ST and the sum of the areas of the titanium alloy particles SJ in the field of view of the _{photograph ;}

Step 4: Optimize the composite powder ball milling mixing process parameters according to the calculated ball milling mixing uniformity value.

Furthermore, the ball milling powder mixing process of the titanium alloy and the ceramic reinforcement phase to be optimized specifically comprises the following steps:

(a) placing spherical titanium alloy particles and ceramic reinforcement phase composite powder to be ball-milled and mixed and stainless steel grinding balls into a ball mill, wherein the mass ratio of the ceramic reinforcement phase to the composite powder is 0.5-8wt%, the mass ratio of the stainless steel grinding balls to the composite powder is (2-7):1, and the diameters of the stainless steel grinding balls are 10 mm, 8 mm, and 5 mm, respectively, corresponding to a mass ratio of 1:3:6;

(b) ball milling the composite powder on a planetary ball mill, setting the ball milling time to 0.5 to 10 hours, the ball milling speed to 50 to 400 rpm, and the ball milling direction to unidirectional rotation or forward and reverse rotation, wherein the unidirectional rotation refers to rotating in the same direction for 60 minutes, stopping for 5 to 10 minutes, and forward and reverse rotation refers to rotating forward for 30 minutes, stopping for 5 to 10 minutes, and rotating reversely for 30 minutes;

(c) At the same ball milling speed and direction, after the ball milling and mixing of powders is started, the planetary ball mill is stopped every 1 hour and the ball mill jar is opened to take out 1-2 g of powder to carry out the step 1 to complete a group of uniformity observations. After 5-10 minutes, the powders are continued to be ball milled and mixed in the ball mill jar, and at least 3 groups are taken out successively for uniformity observations.

Furthermore, the specific process of spreading the composite powder on the conductive adhesive in the step 1 is as follows: cut 5×(10-15) mm of the conductive adhesive and spread it on the sample stage of the scanning electron microscope, select a 5×(5-8) mm area on the conductive adhesive, spread 0.5-1 g of the composite powder in this area, use an ear blower to blow off the composite powder that is not adhered to the conductive adhesive, and repeat the blowing at least 5 times.

Furthermore, the specific steps of obtaining the sum of the areas of the free ceramic reinforcement phase powder and _titanium alloy particles in the field of view of the photograph in step 3 are: performing color separation processing on the image of the field of view of the photograph, marking the free ceramic reinforcement phase powder and titanium alloy particles in the field of view as black according to the principle that the contrast between the titanium alloy particles and the ceramic reinforcement phase powder and the conductive adhesive is different, and the area of the black part is automatically calculated to obtain the sum of the areas S _T in units of µm ² ;

Furthermore, the specific steps of obtaining the sum of the areas S _J of the titanium alloy particles in the field of view of the photograph in step 3 are: selecting the titanium alloy particles in the field of view of the photograph, then filling the selected field of view area with red, and automatically calculating the area of the red part to obtain the sum of the areas S _J of the titanium alloy particles in units of µm ² .

Furthermore, the software used to process the field area image of the microscopic scanning photo is Image pro plus software.

Furthermore, the sum of the areas of the spherical titanium alloy particles ^{before ball milling and mixing in the field of view of the photograph in step 3 is obtained, S 2 is in µm 2} , _{and is} calculated using the following formula:

，

,

Where: S _J is the sum of the areas of the titanium alloy particles in the field of view of the microscopic scanning photo, in µm ² ; R is the average radius of the titanium alloy particles, in µm; r is the average radius of the ceramic reinforcement phase powder, in µm.

，列出所述钛合金和陶瓷增强相球磨混粉工艺参数对球磨混粉复合粉末的区域均匀性的影响表，实现了对钛合金和陶瓷增强相球磨混粉工艺参数的优化。Furthermore, the regional uniformity value of the composite powder is obtained by using the ball milling powder uniformity model.

, a table showing the influence of the ball milling mixing process parameters of the titanium alloy and the ceramic reinforcement phase on the regional uniformity of the ball milling mixed powder composite powder is listed, and the optimization of the ball milling mixing process parameters of the titanium alloy and the ceramic reinforcement phase is achieved.

，即以该定义的复合粉末球磨混粉均匀性模型为依据，能够精确描述工艺参数对制备网状钛基复合材料的复合粉末球磨混粉均匀性的影响，从而优化了金属基复合材料复合粉末制备工艺参数，进而获得了均匀分布的钛合金和陶瓷增强相复合粉末，方便了工业化应用；同时本优化工艺可应用在其他合金或者陶瓷增强相的球磨混粉工艺中。The beneficial effects of the present invention are: the overall uniformity M and regional uniformity of the titanium alloy and ceramic reinforced phase composite powder during the ball milling process are improved.

That is, based on the composite powder ball milling mixing uniformity model defined in this definition, the influence of process parameters on the composite powder ball milling mixing uniformity for preparing reticular titanium-based composite materials can be accurately described, thereby optimizing the process parameters for preparing metal-based composite material composite powders, and then obtaining uniformly distributed titanium alloy and ceramic reinforcement phase composite powders, which is convenient for industrial application; at the same time, this optimization process can be applied to the ball milling mixing process of other alloys or ceramic reinforcement phases.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1: Schematic diagram of the overall uniformity of the Ti6242 and TiB ₂ composite powders of the defined ball-milled mixed powders, where (a) is a schematic diagram of overall uniformity and (b) is a schematic diagram of overall inhomogeneity;

Figure 2: Scanning image photos of the overall inhomogeneity of the ball-milled mixed powder Ti6242 and TiB ₂ composite powder, where (a) is a low-magnification scanning image photo and (b) is a high-magnification scanning image photo;

Figure 3: High-magnification scanning images of the ball-milled Ti6242/TiB ₂ composite powder at different ball-milling times, where (a) is 3h and (b) is 7h;

Figure 4: Schematic diagram of the area S _J and _ST of the Ti6242/TiB ₂ composite powder quantitatively ball-milled using Image pro plus software;

Figure 5: The effect of ball milling process parameters on the uniformity of the ball milling mixing area of Ti6242/ _TiB2 composite powder.

DETAILED DESCRIPTION

The principles and features of the present invention are described below in conjunction with the accompanying drawings. The examples given are only used to explain the present invention and are not used to limit the scope of the present invention.

In order to achieve the above object, the present invention provides the following specific implementation methods:

Embodiment 1: A method for optimizing the ball milling mixing process of titanium alloy and ceramic reinforcement phase based on uniformity, comprising the following steps:

Step 1, take the composite powder of titanium alloy and ceramic reinforcement phase obtained under the ball milling mixing process parameters to be optimized, spread the composite powder on the conductive glue, randomly select at least 3 composite powder areas on the conductive glue, and take microscopic scanning photos in each area with two magnification ranges of 50-80 and 300-400 respectively; the specific process of spreading the composite powder on the conductive glue is: cut 5×(10-15) mm conductive glue and spread it on the scanning electron microscope sample stage, select a 5×(5-8) mm area on the conductive glue, spread 0.5-1 g of composite powder in this area, use a blower to blow off the composite powder that is not adhered to the conductive glue, and blow it repeatedly at least 5 times.

Step 2, take the microscopic scanning photos in the range of 50 to 80 times described in step 1, and observe whether there is a distribution and aggregation phenomenon of 10 or more ceramic reinforcing phase powders gathered together within the range of the photo; the ceramic reinforcing phase powder in the composite powder is overall distributed and aggregated, that is, it is determined to be overall uneven, and the ceramic reinforcing phase powder in the composite powder does not appear to be distributed and aggregated, that is, it is determined to be overall uniform. After the overall uniformity is determined, take out the microscopic scanning photos of 300 to 400 times corresponding to the microscopic scanning photos of 50 to 80 times of the overall uniformity;

Step 3: Take the 300-400 times microscope scan obtained in step 2, and establish a ball milling mixing uniformity model of titanium alloy and ceramic reinforcement phase composite powder in the field of view of the microscope scan:

，

,

为所述复合粉末的区域均匀性；S ₁为游离的陶瓷增强相面积之和，单位为µm²；S ₂为未球磨混粉前的球形钛合金颗粒的面积之和，单位为µm²；n ₁为游离的陶瓷增强相的个数；n ₂为球形钛合金颗粒的个数；ρ ₁为陶瓷增强相密度，单位为g·cm^-3；ρ ₂为钛合金密度，单位为g·cm^-3；ω为陶瓷增强相的相对质量分数；In the formula,

is the regional uniformity of the composite powder; S1 _is the sum of the areas of the free ceramic reinforcement phase, in ^µm2 ; S2 is the sum of the areas of the spherical titanium alloy particles before ball milling , in µm2; n1 is the number of free ceramic reinforcement phases; n2 is the number of spherical titanium alloy particles; ρ1 ^is the _{density of the} ceramic reinforcement phase _, in g·cm ^-3 ; ρ2 is the density of the _titanium alloy, in g·cm ^-3 ; ω is the relative mass fraction of the ceramic reinforcement phase;

_The sum of the areas of the free ceramic reinforcement phase S1 refers to the difference between the sum of the areas of the free ceramic reinforcement phase powder and the titanium alloy particles ST and the sum of the areas of the titanium alloy particles SJ in the field of view of the _{photograph ;}

The specific steps of obtaining the sum of the areas of the free ceramic reinforcement phase powder and the titanium alloy particles S _T in the field of view of the photograph in step 3 are: performing color separation processing on the image of the field of view of the photograph, marking the free ceramic reinforcement phase powder and the spherical titanium alloy particles in the field of view as black according to the principle that the contrast between the titanium alloy spherical particles and the ceramic reinforcement phase powder and the conductive adhesive is different, and the area of the black part is selected and automatically calculated to obtain the sum of the areas S _T in units of µm ² ;

The specific steps of obtaining the sum of the areas S _J of the titanium alloy particles in the field of view of the photograph in step 3 are: selecting the titanium alloy particles in the field of view of the photograph, then filling the selected field of view area with red, and automatically calculating the area of the red part to obtain the sum of the areas S _J of the titanium alloy particles in units of µm ² .

The sum of the areas of the spherical titanium alloy particles before ball milling and mixing in the field of view of the photograph in step 3 is obtained _, S ₂ in units of µm ² , and is calculated using the following formula:

，

,

Where: S _J is the sum of the areas of the titanium alloy particles in the field of view of the microscopic scanning photo, in µm ² ; R is the average radius of the titanium alloy particles, in µm; r is the average radius of the ceramic reinforcement phase powder, in µm.

The software used to process the field area image of the microscopic scanning photo is Image pro plus software.

，列出所述钛合金和陶瓷增强相球磨混粉工艺参数对球磨混粉复合粉末的区域均匀性的影响表，实现了对钛合金和陶瓷增强相球磨混粉工艺参数的优化。Step 4: Optimize the composite powder ball milling process parameters according to the calculated ball milling powder mixing uniformity value. The regional uniformity value of the composite powder is obtained by using the ball milling powder mixing uniformity model.

, a table showing the influence of the ball milling mixing process parameters of the titanium alloy and the ceramic reinforcement phase on the regional uniformity of the ball milling mixed powder composite powder is listed, and the optimization of the ball milling mixing process parameters of the titanium alloy and the ceramic reinforcement phase is achieved.

The ball milling powder mixing process of the titanium alloy and the ceramic reinforcement phase to be optimized specifically comprises the following steps:

(a) placing spherical titanium alloy particles and ceramic reinforcement phase composite powder to be ball-milled and mixed and stainless steel grinding balls into a ball mill, wherein the mass ratio of the ceramic reinforcement phase to the composite powder is 0.5-8wt%, the mass ratio of the stainless steel grinding balls to the composite powder is (2-7):1, and the diameters of the stainless steel grinding balls are 10 mm, 8 mm, and 5 mm, respectively, corresponding to a mass ratio of 1:3:6;

(b) ball milling the composite powder on a planetary ball mill, setting the ball milling time to 0.5 to 10 hours, the ball milling speed to 50 to 400 rpm, and the ball milling direction to unidirectional rotation or forward and reverse rotation, wherein the unidirectional rotation refers to rotating in the same direction for 60 minutes, stopping for 5 to 10 minutes, and forward and reverse rotation refers to rotating forward for 30 minutes, stopping for 5 to 10 minutes, and rotating reversely for 30 minutes;

(c) At the same ball milling speed and ball milling direction, after ball milling and mixing for 3-4 hours, the planetary ball mill is stopped every hour and the ball mill jar is opened to take out 1-2 g of powder to carry out the step 1 to complete a group of uniformity observation. After 5-10 minutes, the powder is continued to be ball milled and mixed in the ball mill jar, and at least 3 groups are taken out successively for uniformity observation.

The present invention is applicable to mixed powders of various titanium alloy particles with spherical morphology and non-spherical ceramic reinforcement particles with adhesion ability. The titanium alloy mainly involved can be any titanium alloy such as Ti6242 and TC4. The ceramic reinforcement phase can be _TiB2 powder, _B4C powder, C powder, etc. The present invention is further described through experimental examples.

Experimental Example: As shown in Figures 1-5, this example takes spherical Ti6242 titanium alloy and _TiB2 ceramic reinforced phase composite powder, and uses the present invention to optimize the process parameters of ball milling and mixing of the two powders. The specific implementation steps are as follows:

(1) 95 g of Ti6242 powder and 5 g of _TiB2 powder were placed in a stainless steel ball mill, and then 500 g of stainless steel grinding balls were added. _TiB2 was irregular in shape with an average particle size of 4 μm, Ti6242 powder was spherical particles with an average particle size of 96 μm, and the diameters of the stainless steel grinding balls were 10 mm, 8 mm, and 5 mm, respectively. The added masses were 50 g, 150 g, and 300 g, respectively.

(2) The Ti6242/TiB ₂ composite powder was ball-milled and mixed on a planetary ball mill for 4 to 10 hours at a ball-milling speed of 200, 300, and 400 rpm in one-way and forward and reverse directions. One-way means rotating in the same direction for 60 minutes and stopping for 10 minutes, and forward and reverse directions means rotating forward for 30 minutes, stopping for 5 minutes, and rotating reversely for 30 minutes.

(3) At the same ball milling speed and ball milling direction, after ball milling for 4 h, the planetary ball mill was stopped and the ball milling jar was opened to take out 1 g of powder every hour. After 10 min, the Ti6242/ _TiB2 composite powder was continued to be ball milled.

(4) Cut a 5×15 mm conductive adhesive and spread it on the sample stage of a TESCAN Vega 2 LMH tungsten filament scanning electron microscope. Select a 5×8 mm area on the conductive adhesive and spread 0.5 g of Ti6242/ _TiB2 composite powder on this area. Use a blower to blow off the Ti6242/ _TiB2 composite powder that is not attached to the conductive adhesive. Repeat this process 10 times.

(5) On a TESCAN Vega 2 LMH tungsten filament scanning electron microscope, three randomly selected areas of the Ti6242/ _TiB2 composite powder adhered to the conductive adhesive were taken at magnifications of 70 and 300 respectively.

(6) Observe the scanning image of the ball-milled Ti6242/ _TiB2 composite powder. If the _TiB2 powder in the composite powder is aggregated less than 10, it is determined to be uniform overall, and the overall uniformity of the ball-milled Ti6242/ _TiB2 composite powder is 1. Then the regional uniformity of the ball-milled composite powder is quantified. If the _TiB2 powder in the composite powder is aggregated with 10 or more, it is determined to be non-uniform overall, and the overall uniformity of the ball-milled Ti6242/ _TiB2 composite powder is 0. There is no need to further quantify the regional uniformity of the ball-milled Ti6242/ _TiB2 composite powder, and the regional uniformity of the composite powder is 0. The calculation results of the overall uniformity of the ball-milled Ti6242/ _TiB2 composite powder are shown in Table 1.

(7) Use Image pro plus software to count the area of free _TiB2 powder and spherical Ti6242 powder in a certain field of view of the scanned image photo. Open the file in the software, click New AOI, select the field of view area, and perform color separation on the image photo after the selected field of view area. According to the principle that the contrast between Ti6242 particles and _TiB2 powder and conductive adhesive is different, the free _TiB2 powder and Ti6242 powder in the field of view area can be marked as red, and the area of the red part can be automatically calculated to obtain the sum of the areas S _T (µm ² ). Similarly, open the image photo after the selected field of view area again, click New AOI and the circular selection tool, use the circular selection tool to select the Ti6242 powder in the field of view area, and then fill the selected field of view area with color, mark it in red, and automatically calculate the area of the red part to obtain the sum of the areas of Ti6242 powder S _J (µm ² ). The sum of the areas of free _TiB2 S ₁ = S _T - S _J.

(8) During the ball milling process, except for the _TiB2 powder that is free in the gap, the rest of the powder adheres to the surface of the Ti6242 particles. The surface of the Ti6242 particles in the field of view is approximately considered to be adhered with a layer of _TiB2 powder. The area of the spherical Ti6242 particles before ball milling is the sum of the areas of the spherical titanium alloy particles S2 _, which is calculated using the following formula. Among them, the average radius R of the Ti6242 particles is 48μm, and the average radius r of the _TiB2 powder is 2μm;

，

,

Where: S ₂ —the sum of the areas of spherical Ti6242 particles before ball milling and mixing (µm ² );

S _J —Sum of the areas of Ti6242 particles in the field of view (µm ² ).

值，(9) Based on the scanned image of the ball-milled Ti6242/ _TiB2 composite powder, the area of free _TiB2 powder and Ti6242 particles in the field of view were counted, and the regional uniformity of the Ti6242/ _TiB2 composite powder in this field of view was calculated using the following formula:

value,

，

,

—球磨混粉的Ti6242/TiB₂复合粉末区域均匀性；Where:

—Regional uniformity of ball-milled Ti6242/TiB ₂ composite powder;

S ₁ —the sum of the areas of free TiB ₂ (µm ² );

S ₂ —the sum of the areas of spherical Ti6242 particles before ball milling and mixing (µm ² );

n ₁ —the number of free TiB ₂ ;

n ₂ —The number of spherical Ti6242 particles.

值为0时，球磨混粉的Ti6242/TiB₂复合粉末区域均匀性最差。球磨混粉的Ti6242/TiB₂复合粉末区域均匀性的计算结果如表2所示。(10) When the regional uniformity is 1, the regional uniformity of the Ti6242/ _TiB2 composite powder obtained by ball milling is the best. At this time, the ball milling mixing process parameters of the Ti6242/ _TiB2 composite powder are the optimal process parameters, and a uniformly distributed Ti6242/ _TiB2 composite powder can be obtained.

When the value is 0, the regional uniformity of the ball-milled Ti6242/TiB ₂ composite powder is the worst. The calculation results of the regional uniformity of the ball-milled Ti6242/TiB ₂ composite powder are shown in Table 2.

Table 1 Overall uniformity values of ball-milled Ti6242/TiB ₂ composite powders

Table 2 Regional uniformity values of Ti6242/TiB ₂ composite powders obtained by ball milling

Conclusion: It can be seen from the above table and Figure 5 that the ball milling direction has no obvious effect on the overall uniformity and regional uniformity of the ball milled Ti6242/TiB ₂ composite powder, and the ball milling speed and ball milling time have a greater impact on the overall uniformity and regional uniformity of the ball milled Ti6242/TiB _{2 composite powder. Under the same ball milling speed, with the extension of ball milling time, the regional uniformity of the Ti6242/TiB 2 composite} powder after ball milling is improved, but when all TiB ₂ powders are adhered to the surface of the spherical Ti6242 matrix powder, the extension of ball milling time affects the regional uniformity of the Ti6242/TiB ₂ composite powder. With the increase of ball milling speed, the Ti6242/TiB ₂ composite powder can achieve uniform distribution at a shorter ball milling time. When the regional uniformity reaches 1, a uniformly distributed Ti6242/TiB ₂ composite powder can be obtained. Taking into account that sphericity will affect the fluidity of Ti6242/ _TiB2 composite powder, as the ball milling time increases, more Ti6242/ _TiB2 composite powder is deformed. Therefore, on the basis of ensuring uniform distribution, considering sphericity and economic effects, the process parameters of ball milling speed of 300 rpm, ball milling time of 8 h, and unidirectional ball milling direction in Experimental Example 1 are the optimal ball milling process parameters for the Ti6242/ _TiB2 composite powder of the present invention.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims (5)

1. The optimization method of the titanium alloy and ceramic reinforced phase ball milling powder mixing process based on uniformity is characterized by comprising the following steps:

firstly, taking composite powder of a titanium alloy and a ceramic reinforcing phase obtained under the process parameters of ball milling and powder mixing to be optimized, spreading and adhering the composite powder on conductive adhesive, randomly selecting at least 3 composite powder areas on the conductive adhesive, and taking microscopic scanning pictures in the two magnification ranges of 50-80 and 300-400 in each area;

step two, taking a microscopic scanning photo in the 50-80 times range in the step one, and observing whether 10 or more than 10 ceramic reinforcing phase powders are aggregated together in the photo range; the ceramic reinforcing phase powder in the composite powder is integrally distributed and aggregated, namely the composite powder is determined to be integrally non-uniform, the ceramic reinforcing phase powder in the composite powder is determined to be integrally uniform, and after the integral uniformity determination is completed, the integral uniform 50-80 times of microscopic scanning photos corresponding to 300-400 times of microscopic scanning photos are taken out;

thirdly, taking a microscopic scanning photo of 300-400 times obtained in the second step, and establishing a titanium alloy and ceramic reinforced phase composite powder ball milling powder mixing uniformity model in the view field of the microscopic scanning photo:

，

wherein:

a regional uniformity for the composite powder;S ₁ is the sum of areas of free ceramic reinforcing phases, and is expressed in [ mu ] m ² ；S ₂ Is the sum of areas of spherical titanium alloy particles before ball milling and powder mixing, and the unit is [ mu ] m ² ；n ₁ The number of the ceramic reinforcing phases is free;n ₂ the number of the spherical titanium alloy particles;ρ ₁ the unit is g cm for the density of the ceramic reinforced phase ^-3 ；ρ ₂ Is titanium alloy density in g cm ^-3 ；ωThe relative mass fraction of the ceramic reinforcing phase;

wherein the sum of the free ceramic reinforcing phase areasS ₁ Refers to the sum of areas of free ceramic reinforcing phase powder and titanium alloy particles in the field of view of the photographS _T Sum of areas with titanium alloy particlesS _J Is the difference between (1);

the sum of areas of free ceramic reinforcing phase powder and titanium alloy particles in the field of view of the photographS _T The specific steps of (a) are as follows: the image of the visual field area of the photo is subjected to color separation treatment, the free ceramic reinforced phase powder and titanium alloy particles in the visual field area are marked as black according to the principle that the contrast of titanium alloy particles, ceramic reinforced phase powder and conductive adhesive is different, and the area selected from the black part is automatically calculated to obtain the sum of areasS _T In [ mu ] m ² ；

The sum of the areas of the titanium alloy particles in the field of view of the photographS _J The specific steps of (a) are as follows: selecting titanium alloy particles in the visual field area of the photo, then performing color filling treatment on the selected visual field area, marking the selected visual field area as red, and automatically calculating the selected area of the red part to obtain the sum of the areas of the titanium alloy particlesS _J In [ mu ] m ² ；

The sum of the areas of the spherical titanium alloy particles in the visual field of the photo before ball milling and powder mixingS ₂ ，S ₂ In [ mu ] m ² The following formula is used for calculation:

，

wherein: s is S _J The unit is [ mu ] m of the sum of areas of titanium alloy particles in a microscopic scanning photo field of view ² The method comprises the steps of carrying out a first treatment on the surface of the R is the average radius of titanium alloy particles, and the unit is mu m; r is the average radius of the ceramic reinforcing phase powder, and the unit is mu m;

and step four, optimizing the process parameters of the ball-milling powder mixing of the composite powder according to the calculated uniformity value of the ball-milling powder mixing.

2. The optimization method of the homogeneity-based titanium alloy and ceramic reinforced phase ball milling powder mixing process according to claim 1, wherein the titanium alloy and ceramic reinforced phase ball milling powder mixing process to be optimized specifically comprises the following steps:

(a) Placing spherical titanium alloy particles needing ball milling and powder mixing, ceramic reinforced phase composite powder and stainless steel grinding balls into a ball milling tank, wherein the ceramic reinforced phase accounts for 0.5-8wt% of the composite powder, the mass ratio of the stainless steel grinding balls to the composite powder is 2-7:1, the diameters of the stainless steel grinding balls are 10mm, 8mm and 5mm respectively, and the corresponding mass ratio is 1:3:6;

(b) Ball milling and mixing the composite powder on a planetary ball mill, wherein the ball milling time is set to be 0.5-10 h, the ball milling rotating speed is set to be 50-400 rpm, the ball milling direction is unidirectional rotation or positive and negative rotation, and the unidirectional rotation means that the composite powder rotates for 60min along the same direction and stops for 5-10 min; the positive and negative rotation means that the rotation is forward for 30min, the stop is carried out for 5-10 min, and the reverse rotation is carried out for 30min;

(c) And under the same ball milling rotating speed and ball milling direction, stopping rotating the planetary ball mill every 1h after starting ball milling and mixing powder, opening a ball milling tank to take out 1-2 g of powder, performing the first step, finishing a group of uniformity observation, continuously performing ball milling and mixing on the powder in the ball milling tank after 5-10 min, and sequentially taking out at least 3 groups for uniformity observation.

3. The optimization method of the titanium alloy and ceramic reinforced phase ball milling powder mixing process based on uniformity according to claim 1, wherein the specific process of flatly spreading and adhering the composite powder on the conductive adhesive in the first step is as follows: cutting off conductive adhesive with the thickness of 5X (10-15) mm, spreading the conductive adhesive on a scanning electron microscope sample table, selecting a region with the thickness of 5X (5-8) mm on the conductive adhesive, spreading 0.5-1 g of composite powder in the region, blowing off the composite powder which is not adhered on the conductive adhesive by using an ear-blowing ball, and repeatedly blowing at least 5 times.

4. The optimization method of the homogeneity-based titanium alloy and ceramic reinforcement phase ball milling powder mixing process according to any one of claims 1-3, wherein software adopted for processing the Image of the field of view region of the micrograph is Image pro plus software.

5. The optimization method of the homogeneity-based titanium alloy and ceramic reinforcement phase ball milling powder mixing process according to any one of claims 1-3, wherein the region homogeneity value of the composite powder is obtained by using the ball milling powder mixing homogeneity model

And (3) listing an influence table of the titanium alloy and ceramic reinforced phase ball-milling powder mixing process parameters on the area uniformity of the ball-milling powder mixing composite powder, and realizing optimization of the titanium alloy and ceramic reinforced phase ball-milling powder mixing process parameters. />

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