阅读说明：本技术 具有复杂形状的硼化钛-碳化硼复合陶瓷及其制造方法 (Titanium boride-boron carbide composite ceramic having complex shape and method for producing same ) 是由 刘江昊 陈倩怡 李智 张海军 张少伟 于 2021-10-29 设计创作，主要内容包括：本发明涉及一种具有复杂形状的硼化钛-碳化硼复合陶瓷及其制造方法。其技术方案是：先将钛粉和碳化硼粉置于混料机中混合,于真空干燥箱中干燥,得到混合粉；将混合粉铺展于选区激光烧结设备的工作仓中,抽真空并充入氩气；再设置选区激光烧结设备的激光加工参数,按照预设模型对铺展的混合粉扫描,制得具有目标形状的硼化钛-碳化硼复合陶瓷；然后将具有目标形状的硼化钛-碳化硼复合陶瓷置于真空管式炉中热处理,制得具有复杂形状的硼化钛-碳化硼复合陶瓷。本发明具有能耗低、效率高、成本低、工艺简单和材料利用率高的特点,所制备的产品形状复杂、致密度高、力学性能优异、表面粗糙度低、精度高和可调范围广。(The invention relates to a titanium boride-boron carbide composite ceramic with a complex shape and a manufacturing method thereof. The technical scheme is as follows: firstly, placing titanium powder and boron carbide powder in a mixer for mixing, and drying in a vacuum drying oven to obtain mixed powder; spreading the mixed powder in a working bin of selective laser sintering equipment, vacuumizing and filling argon; setting laser processing parameters of selective laser sintering equipment, and scanning the spread mixed powder according to a preset model to prepare titanium boride-boron carbide composite ceramic with a target shape; then placing the titanium boride-boron carbide composite ceramic with the target shape into a vacuum tube furnace for heat treatment to prepare the titanium boride-boron carbide composite ceramic with a complex shape. The invention has the characteristics of low energy consumption, high efficiency, low cost, simple process and high material utilization rate, and the prepared product has the advantages of complex shape, high density, excellent mechanical property, low surface roughness, high precision and wide adjustable range.)

1. A preparation method of titanium boride-boron carbide composite ceramic with a complex shape is characterized by comprising the following steps:

firstly, placing 33-75 wt% of titanium powder and 25-67 wt% of boron carbide powder in a mixer, mixing for 3-6 h, then placing in a vacuum drying oven, and drying for 24-36 h at the temperature of 60-70 ℃ to obtain mixed powder;

secondly, spreading the mixed powder in a working bin of selective laser sintering equipment, vacuumizing until the vacuum degree is less than or equal to 100Pa, and filling argon into the working bin to 1 standard atmospheric pressure;

step three, setting laser processing parameters of the selective laser sintering equipment: the output power is 100-500W, the scanning speed is 100-400 mm/s, the scanning distance is 0.02-0.06 mm, the layering thickness is 0.05-0.09 mm, the powder feeding coefficient is 4-7, and the scanning mode is block scanning or strip X-Y;

step four, starting selective laser sintering equipment, and scanning the spread mixed powder for 1-3 times according to a preset model, wherein the scanning interval time is 10-20 s; repeating the steps to a preset height to prepare the titanium boride-boron carbide composite ceramic with the target shape;

and fifthly, placing the titanium boride-boron carbide composite ceramic with the target shape into a vacuum tube furnace, preserving the heat for 1-5 hours at 1100-1500 ℃, and naturally cooling to obtain the titanium boride-boron carbide composite ceramic with the complex shape.

2. The method for producing a titanium boride-boron carbide composite ceramic having a complicated shape according to claim 1, wherein the purity of the titanium powder is not less than 99.9 wt%, and the average particle diameter is not more than 80 μm.

3. The method according to claim 1, wherein the purity of the boron carbide powder is 95.00 wt% or more and the average particle diameter is 80 μm or less.

4. A titanium boride-boron carbide composite ceramic having a complex shape, characterized in that the titanium boride-boron carbide composite ceramic having a complex shape is a titanium boride-boron carbide composite ceramic having a complex shape prepared by the method for preparing a titanium boride-boron carbide composite ceramic having a complex shape according to any one of claims 1 to 3.

Technical Field

The invention belongs to the technical field of titanium boride-boron carbide composite ceramics. In particular to titanium boride-boron carbide composite ceramic with a complex shape and a manufacturing method thereof.

Background

Titanium boride-boron carbide (TiB)₂/B₄C) The composite ceramic has the characteristics of high melting point, high hardness, excellent erosion resistance, excellent thermal shock resistance and the like, and is widely applied to the fields of high-end structural materials such as aerospace, light armor and the like. Therefore, a method for efficiently and inexpensively preparing titanium boride-boron carbide composite ceramics having high density and a complicated shape attracts more and more attention of researchers.

The existing methods for preparing the titanium boride-boron carbide composite ceramic comprise a hot pressing sintering method, a discharge plasma sintering method, a hot isostatic pressing sintering method and the like, which belong to the category of material reduction manufacturing methods, namely, a product with a required complex shape can be obtained only by subsequent processing treatment such as cutting, grinding and polishing. For example, "a B₄C-nanoTiB₂A preparation method of a composite ceramic material (CN110386819A) 'patent technology' comprises the steps of firstly uniformly mixing 90-95% of boron carbide powder and 5-10% of titanium powder in molar fraction, then carrying out vacuum heat treatment to prepare a blank, then placing the obtained blank in a cubic press, and reacting for 10-30 minutes under the conditions that the external pressure is up to 4.5-5.5 GPa and the heating temperature is up to 1400-1600 ℃, thereby preparing B₄C-nanoTiB₂Composite ceramics. ' A₄C/TiB₂A process for preparing laminated composite ceramic material (CN110282977A) includes such steps as proportionally mixing boron carbide powder, titanium boride powder or mixture of boron carbide and titanium boride with carbon source to obtain mixture, die pressingAnd carbonizing at 700-800 ℃ and carrying out vacuum melting siliconizing at 1500-1600 ℃/30-60 minutes under severe temperature conditions to finally prepare the layered titanium boride-boron carbide composite ceramic material with low density and large grain size. Fan et al (Fan JZ, Shen JX, Zhang ZF, et al properties ofB₄C/TiB₂ceramics preparedby sparkplasma sintering[J]Chinese Physics B,2021,30(03): 579-584) discloses a method for preparing boron carbide/titanium boride composite ceramic, which comprises using boron carbide powder (99.5%, 1-10 μm) and titanium hydride powder (99%, 35-45 μm) as raw materials, and preparing the boron carbide/titanium boride composite ceramic with a simple wafer shape by a spark plasma sintering method. The existing material reduction manufacturing method of the titanium boride-boron carbide composite ceramic has the technical defects of high energy consumption, low efficiency, low material utilization rate and high equipment and processing cost, and the product has the defects of low density, poor mechanical property, low surface precision, small size, no complex shape and the like, thereby seriously limiting the exertion of the application value.

A Selective Laser Sintering (SLS) method is used as a representative additive manufacturing method, and a three-dimensional structure model of a printing material is designed by using modeling software, and by controlling Laser to perform Selective processing and stacking of processing layers on a two-dimensional layer according to a preset path, a product with any three-dimensional structure is directly prepared. Therefore, compared with material reduction manufacturing methods, additive manufacturing methods such as selective laser sintering methods and the like have the advantages of low energy consumption, high efficiency, high material utilization rate, low cost, capability of forming materials with required complex shapes without using a die and the like.

Currently, few reports of preparing ceramics by selective laser sintering methods are reported and oxide ceramics are the main. In contrast, there are significantly fewer reports on non-oxide ceramics and no reports on the preparation of titanium boride and boron carbide ceramics. For example, Bertrand et al (Bertrand P, Bayle F, Comme C, et al]Applied Surface Science,2007,254(4):989-₂-Y₂O₃A ceramic. Yves-Christian et al (Yves-Christian H, Jan W, Wilhelm M, et al.Net shaped high performance oxide partial by selective laser long [ J]Physics Procedia,2010,5:587-₂O₃-ZrO₂A ceramic. Zhang et al (Zhang X, Wang F, Wu Z, et al direct selective laser sintering of hexagonal barum titanate ceramics [ J]Journal of American Ceramic Society,2021,104:1271-₃A ceramic membrane. Gu et al (Gu D, Shen Y, Lu Z₅Si₃ in-situ composites by Selective Laser Melting[J]Materials Letters,2009,63(18-19):1577-1579.) titanium powder and silicon nitride powder are used as raw Materials, and a selective laser sintering method is adopted to prepare TiN/Ti with lower purity by in-situ synthesis/sintering₅Si₃A composite material.

The main problems of the selective laser sintering method for preparing the ceramic are that the melting point of the ceramic is high, the covalent bond property is strong, and the laser absorption capacity is poor, so that the ceramic is difficult to be fully sintered under the laser processing condition. Therefore, the existing selective laser sintering method for preparing ceramics generally has the defects of narrow printing material range, high energy consumption processing conditions such as preheating and the like, lower product purity and density, higher surface roughness, poor mechanical property and the like.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and aims to provide the method for manufacturing the titanium boride-boron carbide composite ceramic with the complex shape, which has the advantages of low energy consumption, high efficiency, low cost, simple process, high material utilization rate and no need of a mould.

In order to achieve the purpose, the technical scheme adopted by the invention comprises the following steps:

firstly, placing 33-75 wt% of titanium powder and 25-67 wt% of boron carbide powder in a mixer, mixing for 3-6 h, then placing in a vacuum drying oven, and drying for 24-36 h at 60-70 ℃ to obtain mixed powder.

And secondly, spreading the mixed powder in a working bin of selective laser sintering equipment, vacuumizing until the vacuum degree is less than or equal to 100Pa, and filling argon into the working bin to 1 standard atmospheric pressure.

Step three, setting laser processing parameters of the selective laser sintering equipment: the output power is 100-500W, the scanning speed is 100-400 mm/s, the scanning distance is 0.02-0.06 mm, the layering thickness is 0.05-0.09 mm, the powder feeding coefficient is 4-7, and the scanning mode is block scanning or strip X-Y.

Step four, starting selective laser sintering equipment, and scanning the spread mixed powder for 1-3 times according to a preset model, wherein the scanning interval time is 10-20 s; and repeating the steps to a preset height to obtain the titanium boride-boron carbide composite ceramic with the target shape.

And fifthly, placing the titanium boride-boron carbide composite ceramic with the target shape into a vacuum tube furnace, preserving the heat for 1-5 hours at 1100-1500 ℃, and naturally cooling to obtain the titanium boride-boron carbide composite ceramic with the complex shape.

The purity of the titanium powder is more than or equal to 99.9 wt%, and the average grain diameter is less than or equal to 80 mu m.

The purity of the boron carbide powder is more than or equal to 95.00 wt%, and the average grain diameter is less than or equal to 80 mu m.

Compared with the prior art, the invention has the following positive effects and prominent characteristics due to the adoption of the technical scheme:

1. the titanium boride-boron carbide composite ceramic with a complex shape is prepared by adopting a selective laser sintering method, belongs to the category of a material increase manufacturing method, and is prepared by scanning spread mixed powder for 1-3 times according to a preset model, wherein the scanning interval time is 10-20 s, and repeating the steps in the above way; and then preserving heat for 1-5 hours at 1100-1500 ℃, and naturally cooling to obtain the product, so that the method has the advantages of low energy consumption, high efficiency, no need of a mold, complex shape, low surface roughness, high precision and adjustable three-dimensional size.

2. The invention takes commercial titanium powder and commercial boron carbide powder as raw materials for preparing the titanium boride-boron carbide composite ceramic with complex shape, and XRD test results show that the titanium boride-boron carbide composite ceramic with complex shape prepared by the in-situ synthesis/sintering method only contains TiB₂Phase B and₄and the phase C is the titanium boride-boron carbide composite ceramic. In the preparation process, the titanium powder absorbs laser energy to form a molten pool and increase the temperature of a reaction system, so that a strong exothermic chemical reaction between the titanium powder and the boron carbide powder is induced, and the synthesis of titanium boride and the sintering process of the titanium boride-boron carbide composite ceramic are synchronously promoted. Therefore, the prepared product has high density and excellent mechanical property.

3. The titanium boride-boron carbide composite ceramic with a complex shape can be prepared by adopting a selective laser sintering method and only matching with simple annealing treatment, so that the tedious post-treatment processes of cutting, grinding and polishing and the like of a material reduction processing method are omitted, and the corresponding processing cost is saved. Therefore, the method has the advantages of simple process, high efficiency, high material utilization rate and low processing cost, and is suitable for industrial production.

Therefore, the method has the characteristics of low energy consumption, high efficiency, low cost, simple process and high material utilization rate, and the prepared titanium boride-boron carbide composite ceramic with a complex shape has the advantages of complex shape, high density, excellent mechanical property, low surface roughness, high precision and wide adjustable range.

Drawings

FIG. 1 is a photograph of a titanium boride-boron carbide composite ceramic having a complicated shape prepared by the present invention;

fig. 2 is an XRD pattern of the titanium boride-boron carbide composite ceramic having a complex shape shown in fig. 1.

Detailed Description

The invention is further described with reference to the following figures and detailed description, without limiting its scope.

In order to avoid repetition, the raw material information related to this specific embodiment is described in a unified manner, which is not described again in the embodiments:

the purity of the titanium powder is more than or equal to 99.9 wt%, and the average grain diameter is less than or equal to 80 mu m;

the purity of the boron carbide powder is more than or equal to 95.00 wt%, and the average grain diameter is less than or equal to 80 mu m.

Example 1

A titanium boride-boron carbide composite ceramic with a complex shape and a manufacturing method thereof. The preparation method comprises the following steps:

firstly, placing 60-75 wt% of titanium powder and 25-40 wt% of boron carbide powder in a mixer, mixing for 5-6 h, then placing in a vacuum drying oven, and drying for 24-28 h at 60-63 ℃ to obtain mixed powder.

And secondly, spreading the mixed powder in a working bin of selective laser sintering equipment, vacuumizing until the vacuum degree is less than or equal to 100Pa, and filling argon into the working bin to 1 standard atmospheric pressure.

Step three, setting laser processing parameters of the selective laser sintering equipment: the output power is 150-300W, the scanning speed is 100-200 mm/s, the scanning interval is 0.02-0.03 mm, the layering thickness is 0.05-0.06 mm, the powder feeding coefficient is 5-6, and the scanning mode is block scanning.

Step four, starting selective laser sintering equipment, and scanning the spread mixed powder for 1-2 times according to a preset model, wherein the scanning interval time is 10-12 s; and repeating the steps to a preset height to obtain the titanium boride-boron carbide composite ceramic with the target shape.

And fifthly, placing the titanium boride-boron carbide composite ceramic with the target shape into a vacuum tube furnace, preserving the heat for 1-2 hours at 1100-1200 ℃, and naturally cooling to obtain the titanium boride-boron carbide composite ceramic with the complex shape.

Example 2

A titanium boride-boron carbide composite ceramic with a complex shape and a manufacturing method thereof. The preparation method comprises the following steps:

firstly, 53-70 wt% of titanium powder and 30-47 wt% of boron carbide powder are placed in a mixer to be mixed for 3.5-4.5 hours, and then the mixture is placed in a vacuum drying oven to be dried for 26-30 hours at the temperature of 62-65 ℃ to obtain mixed powder.

And secondly, spreading the mixed powder in a working bin of selective laser sintering equipment, vacuumizing until the vacuum degree is less than or equal to 100Pa, and filling argon into the working bin to 1 standard atmospheric pressure.

Step three, setting laser processing parameters of the selective laser sintering equipment: the output power is 100-250W, the scanning speed is 200-300 mm/s, the scanning interval is 0.02-0.03 mm, the layering thickness is 0.07-0.08 mm, the powder feeding coefficient is 6-7, and the scanning mode is block scanning.

Step four, starting selective laser sintering equipment, and scanning the spread mixed powder for 2-3 times according to a preset model, wherein the scanning interval time is 12-14 s; and repeating the steps to a preset height to obtain the titanium boride-boron carbide composite ceramic with the target shape.

And fifthly, placing the titanium boride-boron carbide composite ceramic with the target shape into a vacuum tube furnace, preserving the heat for 2-3 hours at 1200-1300 ℃, and naturally cooling to obtain the titanium boride-boron carbide composite ceramic with the complex shape.

Example 3

A titanium boride-boron carbide composite ceramic with a complex shape and a manufacturing method thereof. The preparation method comprises the following steps:

firstly, placing 46-58 wt% of titanium powder and 42-54 wt% of boron carbide powder in a mixer, mixing for 4.5-5.5 h, then placing in a vacuum drying oven, and drying for 28-32 h at 64-67 ℃ to obtain mixed powder.

And secondly, spreading the mixed powder in a working bin of selective laser sintering equipment, vacuumizing until the vacuum degree is less than or equal to 100Pa, and filling argon into the working bin to 1 standard atmospheric pressure.

Step three, setting laser processing parameters of the selective laser sintering equipment: the output power is 200-350W, the scanning speed is 150-250 mm/s, the scanning distance is 0.03-0.04 mm, the layering thickness is 0.06-0.07 mm, the powder feeding coefficient is 4-5, and the scanning mode is a strip X-Y.

Step four, starting selective laser sintering equipment, and scanning the spread mixed powder for 2-3 times according to a preset model, wherein the scanning interval time is 14-16 s; and repeating the steps to a preset height to obtain the titanium boride-boron carbide composite ceramic with the target shape.

And fifthly, placing the titanium boride-boron carbide composite ceramic with the target shape into a vacuum tube furnace, preserving the heat for 3-4 hours at 1400-1500 ℃, and naturally cooling to obtain the titanium boride-boron carbide composite ceramic with the complex shape.

Example 4

A titanium boride-boron carbide composite ceramic with a complex shape and a manufacturing method thereof. The preparation method comprises the following steps:

firstly, putting 38-51 wt% of titanium powder and 49-62 wt% of boron carbide powder into a mixer, mixing for 4-5 h, then putting into a vacuum drying oven, and drying for 32-36 h at 68-70 ℃ to obtain mixed powder.

And secondly, spreading the mixed powder in a working bin of selective laser sintering equipment, vacuumizing until the vacuum degree is less than or equal to 100Pa, and filling argon into the working bin to 1 standard atmospheric pressure.

Step three, setting laser processing parameters of the selective laser sintering equipment: the output power is 250-400W, the scanning speed is 250-350 mm/s, the scanning distance is 0.04-0.05 mm, the layering thickness is 0.06-0.07 mm, the powder feeding coefficient is 5-6, and the scanning mode is block scanning.

Step four, starting selective laser sintering equipment, and scanning the spread mixed powder for 1-2 times according to a preset model, wherein the scanning interval time is 16-18 s; and repeating the steps to a preset height to obtain the titanium boride-boron carbide composite ceramic with the target shape.

And fifthly, placing the titanium boride-boron carbide composite ceramic with the target shape into a vacuum tube furnace, preserving the heat for 4-5 hours at 1300-1400 ℃, and naturally cooling to obtain the titanium boride-boron carbide composite ceramic with the complex shape.

Example 5

A titanium boride-boron carbide composite ceramic with a complex shape and a manufacturing method thereof. The preparation method comprises the following steps:

firstly, placing 33-45 wt% of titanium powder and 55-67 wt% of boron carbide powder in a mixer, mixing for 3-4 h, then placing in a vacuum drying oven, and drying for 30-34 h at 65-68 ℃ to obtain mixed powder.

And secondly, spreading the mixed powder in a working bin of selective laser sintering equipment, vacuumizing until the vacuum degree is less than or equal to 100Pa, and filling argon into the working bin to 1 standard atmospheric pressure.

Step three, setting laser processing parameters of the selective laser sintering equipment: the output power is 350-500W, the scanning speed is 300-400 mm/s, the scanning interval is 0.05-0.06 mm, the layering thickness is 0.08-0.09 mm, the powder feeding coefficient is 4-5, and the scanning mode is a strip X-Y.

Step four, starting selective laser sintering equipment, and scanning the spread mixed powder for 2-3 times according to a preset model, wherein the scanning interval time is 18-20 s; and repeating the steps to a preset height to obtain the titanium boride-boron carbide composite ceramic with the target shape.

And fifthly, placing the titanium boride-boron carbide composite ceramic with the target shape into a vacuum tube furnace, preserving the heat for 2-3 hours at 1350-1450 ℃, and naturally cooling to obtain the titanium boride-boron carbide composite ceramic with the complex shape.

Compared with the prior art, the specific implementation mode has the following positive effects and outstanding characteristics:

1. the method adopts a selective laser sintering method to prepare the titanium boride-boron carbide composite ceramic with a complex shape, belongs to the category of additive manufacturing methods, and only needs to scan the spread mixed powder for 1-3 times according to a preset model, wherein the scanning interval time is 10-20 s, and the scanning is repeated in such a way, so that the titanium boride-boron carbide composite ceramic with a target shape is obtained; and then preserving heat for 1-5 h at 1100-1500 ℃, and naturally cooling to obtain the titanium boride-boron carbide composite ceramic with a complex shape as shown in figure 1. FIG. 1 is a photograph of a titanium boride-boron carbide composite ceramic having a complicated shape prepared in example 1, and it can be seen from FIG. 1 that: the manufactured product has complex shape and high precision; therefore, the embodiment has the advantages of low energy consumption, high efficiency, no need of a die, complex shape, low surface roughness, high precision and adjustable three-dimensional size.

2. In the specific embodiment, commercial titanium powder and commercial boron carbide powder are used as raw materials for preparing the titanium boride-boron carbide composite ceramic with the complex shape, and the titanium boride-boron carbide composite ceramic with the complex shape is prepared by an in-situ synthesis/sintering method. The XRD test result of the prepared product is shown in figure 2, figure 2 is the XRD pattern of the titanium boride-boron carbide composite ceramic with complex shape shown in figure 1, and as can be seen from figure 2, the prepared product only contains TiB₂Phase B and₄and the phase C is the titanium boride-boron carbide composite ceramic. In the preparation process of the specific embodiment, the titanium powder absorbs laser energy to form a molten pool and increase the temperature of a reaction system, so that a strong exothermic chemical reaction between the titanium powder and the boron carbide powder is induced, and the synthesis of titanium boride and the sintering process of the titanium boride-boron carbide composite ceramic are synchronously promoted. Therefore, the prepared product has high density and excellent mechanical property.

3. The specific embodiment adopts the selective laser sintering method, and can prepare the titanium boride-boron carbide composite ceramic with a complex shape only by matching with simple annealing treatment, thereby omitting the tedious post-treatment processes of cutting, grinding and polishing and the like of a material reduction processing method and saving the corresponding processing cost. Therefore, the method has the advantages of simple process, high efficiency, high material utilization rate and low processing cost, and is suitable for industrial production.

Therefore, the specific embodiment has the characteristics of low energy consumption, high efficiency, low cost, simple process and high material utilization rate, and the prepared titanium boride-boron carbide composite ceramic with a complex shape has the advantages of complex shape, high density, excellent mechanical property, low surface roughness, high precision and wide adjustable range.