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CN110629143B - Method for in-situ synthesis of fibrous nano tungsten carbide on surface layer of hard alloy - Google Patents

Method for in-situ synthesis of fibrous nano tungsten carbide on surface layer of hard alloy Download PDF

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CN110629143B
CN110629143B CN201911033947.1A CN201911033947A CN110629143B CN 110629143 B CN110629143 B CN 110629143B CN 201911033947 A CN201911033947 A CN 201911033947A CN 110629143 B CN110629143 B CN 110629143B
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electron beam
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tungsten carbide
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郝胜智
彭文海
卢健
吴垚
杨勃行
姜梦琦
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Dalian University of Technology
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    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
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    • C22F1/00Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
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Abstract

一种硬质合金表层原位合成纤维状纳米碳化钨的方法,属于材料技术领域。通过利用强流脉冲电子束和低温回火,对硬质合金表层进行显微结构调控,强流脉冲电子束辐照的表层微区在满足纳米亚稳组织形成的热动力学和结晶学条件,而温度低于烧结温度的回火,使得固态相变仅仅发生于硬质合金表层的亚稳态组织中。制备时,(1)对硬质合金块体表面进行打磨后,清洗风干;(2)对硬质合金块体进行强流脉冲电子束表面辐照处理;(3)将辐照后的硬质合金块体置于真空管式炉中进行低温回火。本发明的工艺简单,可靠性高,操作方便;硬质合金表层晶粒快速熔凝及固态相变后得到的纳米碳化钨复合结构,这种稳定的纤维状纳米结构起到强化硬质合金表面的作用。

Figure 201911033947

The invention relates to a method for in-situ synthesis of fibrous nano-tungsten carbide on the surface of a hard alloy, belonging to the technical field of materials. Through the use of high-current pulsed electron beam and low-temperature tempering, the microstructure of cemented carbide surface is controlled. The tempering temperature is lower than the sintering temperature, so that the solid-state transformation only occurs in the metastable structure of the cemented carbide surface. During preparation, (1) grinding the surface of the cemented carbide block, cleaning and air-drying; (2) irradiating the surface of the cemented carbide block with high-current pulsed electron beams; (3) irradiating the hard alloy block. The alloy block is placed in a vacuum tube furnace for low temperature tempering. The process of the invention is simple, the reliability is high, and the operation is convenient; the nano-tungsten carbide composite structure is obtained after the crystal grains on the surface of the cemented carbide are rapidly fused and solid-state phase transformation, and the stable fibrous nano-structure can strengthen the surface of the cemented carbide. effect.

Figure 201911033947

Description

Method for in-situ synthesis of fibrous nano tungsten carbide on surface layer of hard alloy
Technical Field
The invention belongs to the technical field of materials, and provides a method for in-situ synthesis of fibrous nano tungsten carbide on a hard alloy surface layer.
Background
The hard alloy is made into cutters and wear-resistant elements due to good mechanical properties, such as high hardness, high strength, good wear resistance and the like, and is widely applied to various fields of industrial production. It is a composite material prepared by powder metallurgy method, mainly composed of hard phase (refractory metal carbide) and binding phase (metal). Research shows that the grain size of the hard phase in the hard alloy has important influence on the mechanical property of the hard alloy, and the hardness, the strength and the wear resistance of the hard alloy material can be simultaneously improved by refining the hard phase grains. For preparing fine-grained cemented carbide, high-energy ball milling, thermochemical synthesis, plasma and mechanical alloying methods have been developed to prepare nanopowders, or metal inhibitors to limit the growth of hard phases have been added during sintering. The application of the hard alloy material is analyzed, and the surface strength and the wear resistance of the hard alloy material can be effectively improved by changing the surface structure of the hard alloy. Therefore, there are technologists working on developing cemented carbides with a gradient structure (i.e., fine surface grains and coarse matrix grains). However, the existing gradient hard alloy preparation process is still imperfect, the process flow is complex, the influence factors are many, and the maintenance cost of production equipment is high.
According to the tungsten-carbon phase diagram, there are three main types of tungsten-carbon compounds, WC and W2C、WC1-x. Wherein WC is the most stable as the hard phase of common cemented carbides; WC1-xIs a metastable phase which is stable at a temperature above 2516 ℃ and below which decomposition to form WC and W occurs2C. The non-equilibrium solidification thermodynamic analysis of the ultra-high-speed cooling shows that the cooling speed of the melt reaches 108Nano-sized WC can be obtained at room temperature at DEG C/s1-x. The irradiation of the high current pulse electron beam can instantly melt and rapidly cool the surface layer of the block hard alloy at a cooling speed of 108-10The temperature/s can meet the non-equilibrium solidification condition, and metastable nanometer WC can be obtained1-x. The stable nanometer WC surface layer can be obtained by properly heating and tempering the structure, and the preparation of the hard alloy with the gradient structure is realized.
Disclosure of Invention
The invention firstly uses strong current pulse electron beam to irradiate the surface of the hard alloy block body to lead the surface crystal grain to be melted and form the metastable nanometer WC in the ultra-high speed non-equilibrium solidification process1-x(ii) a And then, tempering the irradiated hard alloy block at a proper low temperature to prepare the gradient structure hard alloy with the nano WC surface layer.
In order to achieve the purpose, the invention adopts the technical scheme that:
a method for in-situ synthesizing fibrous nanometer tungsten carbide on a hard alloy surface layer is characterized in that a strong current pulse electron beam and low-temperature tempering treatment are adopted to prepare a fibrous nanometer tungsten carbide composite structure in situ on the hard alloy block surface layer, the structure and the performance in the hard alloy block are not changed, the obtained fibrous nanometer tungsten carbide composite structure is fine in surface layer structure and high in hardness and strength, the special fibrous structure is also beneficial to improving the wear resistance of the hard alloy surface, and the method specifically comprises the following steps:
(1) pretreatment of cemented carbide blocks
And (3) polishing the surface of the hard alloy block sample by using a diamond grinding disc, then sequentially carrying out ultrasonic oscillation cleaning for 5-15min by using alcohol and deionized water, and drying by cold air to obtain the hard alloy block.
The polishing specifically comprises the following steps: and diamond millstones of 180#, 360#, 800#, and 1200# are selected in sequence for polishing to obtain a smoother surface, which is favorable for the electron beam energy to act on the micro-area of the surface layer of the hard alloy more uniformly.
(2) Inducing surface nano metastable tissue by irradiation of high current pulse electron beam
Fixing the hard alloy block obtained in the step (1) on a sample target in a vacuum chamber of a high-current pulse electron beam device according to the polished surface and the direction vertical to the electron beam axis, wherein the air pressure in the vacuum chamber is 5.5-7.5 multiplied by 10-3Pa, electron beam energy density 2-8J/cm2Irradiating for 6-20 times under the conditions of the accelerating voltage of 27keV, the pulse width of 0.5-6 mus and the target pole distance of 10-15cm to obtain the hard alloy block with the nano metastable tissue on the surface layer.
(3) Inducing nano metastable organization solid phase transition by utilizing low-temperature tempering
And (3) placing the hard alloy block obtained in the step (2) into a vacuum tube furnace, vacuumizing, and introducing Ar gas for protection. The temperature of the tubular furnace is raised to 550-750 ℃ at the speed of 5-15 ℃/min, the temperature is kept for 0.5-2.5 hours, and then the temperature is cooled to room temperature along with the furnace, so that the gradient hard alloy block with the fibrous nano tungsten carbide on the surface layer is obtained, the internal structure of the hard alloy block is unchanged, and the fibrous nano tissue on the surface layer has better hardness, strength and wear resistance, thereby playing a good protection role.
The obtained surface fibrous gradient hard alloy block is subjected to surface microhardness test, the surface microhardness of the obtained surface fibrous gradient hard alloy block is greatly improved compared with that of a hard alloy block which is not subjected to any treatment, and the prepared gradient hard alloy block can be applied to wear-resistant parts such as cutting tools, drill bits, dies and the like, so that the service life of the parts, the processing precision and the quality of workpieces are improved.
The invention has the beneficial effects that:
(1) the energy density of the high-current pulse electron beam is high, and the temperature condition of the irradiation induction surface micro-area is more favorable for the hard alloy surface layer to form a fine nano metastable state structure; annealing the metastable structure at low temperature can form stable fibrous tungsten carbide with the same scale through solid-state phase transition.
(2) The whole preparation process is simple in flow, high in reliability and few in influencing factors; the prepared hard alloy with the fibrous nano-structure surface layer has higher surface hardness and better surface wear resistance.
Drawings
Fig. 1 is a scanning electron micrograph of untreated sintered cemented carbide.
FIG. 2 is the SEM image of the surface of the cemented carbide after the irradiation of the high current pulsed electron beam in example 2.
FIG. 3 is the SEM photograph of the surface of the cemented carbide after low temperature tempering in example 2.
FIG. 4 is a comparison of the micro-hardness of the surface of the cemented carbide of example 2.
Detailed Description
The present invention will be described in more detail with reference to the following examples, which are not intended to limit the scope of the present invention.
Example 1:
(1) pretreatment: grinding YG10 hard alloy (WC average particle size is 1.27 μm) blocks by 180#, 360#, 800# and 1200# diamond grinding discs in sequence, then ultrasonically cleaning by ethanol and deionized water for 10min in sequence and blow-drying by cold air;
(2) the pre-treated YG10 hard metal block was fixed to a sample target inside the vacuum chamber of a high current pulsed electron beam device. Vacuum-pumping to 7.0 × 10-3And (3) starting pulsed electron beam irradiation on the surface of the sample at Pa, and performing irradiation 20 times. Energy density of electron beam 6J/cm2Accelerating voltage 27keV, pulse width 2.5 mus, target pole distance 12.5 cm;
(3) and placing the YG10 hard alloy block irradiated by the electron beam in a vacuum tube furnace, vacuumizing, and introducing Ar gas for protection. The temperature of the tube furnace is raised to 600 ℃ at the speed of 10 ℃/min, the temperature is kept for 1.5 hours, and then the tube furnace is cooled to the room temperature.
Example 2:
(1) pretreatment: grinding the YG10 hard alloy block by using a 180#, 360#, 800# and 1200# diamond grinding disc in sequence, then ultrasonically cleaning for 15min by using ethanol and deionized water in sequence, and drying by cold air;
(2) the pre-treated YG10 hard metal block was fixed to a sample target inside the vacuum chamber of a high current pulsed electron beam device. Vacuum-pumping to 5.5X 10-3And when Pa, starting pulsed electron beam to irradiate the surface of the sample for 6 times. Energy density of electron beam 8J/cm2The accelerating voltage is 27keV, the pulse width is 6 microseconds, the target pole distance is 15 centimeters, the surface appearance of the hard alloy after the irradiation of the high-current pulse electron beam is observed by using a scanning electron microscope and is shown in figure 2;
(3) and placing the YG10 hard alloy block irradiated by the electron beam in a vacuum tube furnace, vacuumizing, and introducing Ar gas for protection. The temperature of the tube furnace is increased to 750 ℃ at the speed of 15 ℃/min, the temperature is kept for 0.5 hour, then the tube furnace is cooled to room temperature, the observation is carried out by utilizing a scanning electron microscope, the surface appearance of the hard alloy after the irradiation of the high-current pulse electron beam is shown in figure 3, and the hard alloy is in a fibrous nano structure.
The surface microhardness of the prepared surface fibrous gradient hard alloy block is greatly improved compared with that of the hard alloy block without any treatment by a surface microhardness test, as shown in fig. 4.
Example 3
(1) Pretreatment: grinding the YG10 hard alloy block by using a 180#, 360#, 800# and 1200# diamond grinding disc in sequence, then ultrasonically cleaning for 5min by using ethanol and deionized water in sequence, and drying by cold air;
(2) will be pretreatedThe rear YG10 hard metal block was fixed on the sample target inside the vacuum chamber of the high current pulsed electron beam device. Vacuum-pumping to 7.5 × 10-3And (3) starting pulsed electron beam irradiation on the surface of the sample at Pa, and irradiating for 15 times. Energy density of electron beam 2J/cm2Accelerating voltage 27keV, pulse width 0.5 mu s, target pole distance 10 cm;
(3) and placing the YG10 hard alloy block irradiated by the electron beam in a vacuum tube furnace, vacuumizing, and introducing Ar gas for protection. The temperature of the tubular furnace is raised to 550 ℃ at the speed of 5 ℃/min, the temperature is kept for 2.5 hours, and then the tubular furnace is cooled to room temperature to obtain the product.
The above-mentioned embodiments only express the embodiments of the present invention, but not should be understood as the limitation of the scope of the invention patent, it should be noted that, for those skilled in the art, many variations and modifications can be made without departing from the concept of the present invention, and these all fall into the protection scope of the present invention.

Claims (3)

1. A method for in-situ synthesizing fibrous nanometer tungsten carbide on a hard alloy surface layer is characterized in that a strong current pulse electron beam and low-temperature tempering treatment are adopted in the preparation method to prepare a fibrous nanometer tungsten carbide composite structure on the hard alloy block surface layer in situ without changing the structure and the performance in the hard alloy block, and the method comprises the following steps:
(1) pretreatment of cemented carbide blocks
Polishing the surface of a hard alloy block sample to obtain a relatively flat surface, then sequentially carrying out ultrasonic oscillation cleaning for 5-15min by using alcohol and deionized water, and drying by cold air;
(2) inducing surface nano metastable tissue by irradiation of high current pulse electron beam
Fixing the hard alloy block obtained in the step (1) on a sample target in a vacuum chamber of a high-current pulse electron beam device according to the polished surface and the direction vertical to the axial direction of an electron beam, and keeping the air pressure in the vacuum chamber at 5.5 multiplied by 10-3-7.5×10-3Pa, electron beam energy density 2-8J/cm2Irradiating for 6-20 times under the conditions of accelerating voltage 27keV, pulse width 0.5-6 mus and target pole distance 10-15cm to obtain the tableA cemented carbide block having a nano metastable structure in a layer;
(3) inducing nano metastable organization solid phase transition by utilizing low-temperature tempering
Placing the hard alloy block obtained in the step (2) in a vacuum tube furnace, vacuumizing, and introducing Ar gas as protection; the temperature of the tube furnace is increased to 550 ℃ and 750 ℃, the temperature is kept constant for 0.5 to 2.5 hours, and then the tube furnace is cooled to room temperature, so as to obtain the gradient hard alloy block body with the fibrous nano tungsten carbide on the surface layer.
2. The method for in-situ synthesis of the fibrous nano tungsten carbide on the surface layer of the hard alloy according to claim 1, wherein in the step (1), 180#, 360#, 800# and 1200# diamond millstones are sequentially selected for surface grinding of the hard alloy block sample.
3. The method for in-situ synthesis of fibrous nano tungsten carbide on the surface layer of cemented carbide as claimed in claim 1 or 2, wherein in the step (3), the temperature rise rate of the tube furnace is 5-15 ℃/min.
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Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0445305A1 (en) * 1989-09-22 1991-09-11 Showa Denko Kabushiki Kaisha Vapor deposited diamond synthesizing method on electrochemically treated substrate
CN102071386A (en) * 2011-01-13 2011-05-25 中南大学 Thermo-magnetic composite file processing technique for hard alloy
CN102154536A (en) * 2010-01-13 2011-08-17 大连理工大学 Method for handling high current pulsed electron beams (HCPEB) on surface of hard alloy cutter
CN107475548A (en) * 2017-06-28 2017-12-15 沈阳寰博磁电科技有限公司 A kind of preparation method of nanometer of toughness reinforcing Ultra-fine Grained WC Co hard alloy
CN109652700A (en) * 2017-10-12 2019-04-19 杨振文 A kind of Irradiated by High-intensity Pulsed Ion Beams WC-Co hard alloy

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0445305A1 (en) * 1989-09-22 1991-09-11 Showa Denko Kabushiki Kaisha Vapor deposited diamond synthesizing method on electrochemically treated substrate
CN102154536A (en) * 2010-01-13 2011-08-17 大连理工大学 Method for handling high current pulsed electron beams (HCPEB) on surface of hard alloy cutter
CN102071386A (en) * 2011-01-13 2011-05-25 中南大学 Thermo-magnetic composite file processing technique for hard alloy
CN107475548A (en) * 2017-06-28 2017-12-15 沈阳寰博磁电科技有限公司 A kind of preparation method of nanometer of toughness reinforcing Ultra-fine Grained WC Co hard alloy
CN109652700A (en) * 2017-10-12 2019-04-19 杨振文 A kind of Irradiated by High-intensity Pulsed Ion Beams WC-Co hard alloy

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
强流脉冲电子束处理对WC-Co硬质合金耐磨性的影响;任鑫等;《金属热处理》;20151025(第10期);第132-134页 *

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