Disclosure of Invention
The invention provides zirconium boride-based ceramic and a preparation method thereof. The zirconium boride-based ceramic prepared by the method has good compactness and high temperature resistance, and can be widely applied to the fields of heating elements, aerospace devices and the like.
The invention provides a preparation method of zirconium boride-based ceramic, which comprises the following steps:
step 1: preparing zirconium boride prilling balls through a prilling process under the alkaline condition that the pH value is 9.2-9.8, and mixing the zirconium boride prilling balls with zirconium dioxide powder to obtain zirconium boride-zirconium dioxide composite powder;
step 2: and carrying out glue discharging and spark plasma sintering on the zirconium boride-zirconium dioxide composite powder to obtain the zirconium boride-based ceramic.
More preferably, the basic conditions in step 1 are specifically pH 9.5.
Preferably, the volume ratio of the zirconium boride granulating ball to the zirconium dioxide powder in the step 1 is (60-99): (1-40).
More preferably, the volume ratio of the zirconium boride granulated ball to the zirconium dioxide powder in step 1 is 4:1 or 85: 15.
Preferably, the zirconium boride prilling ball is prepared by the following steps:
step a: adding organic base into deionized water, adjusting the pH value to 9.2-9.8, adding zirconium boride powder, and stirring to obtain a first slurry;
step b: adding a binder into the first slurry for ball milling to obtain a second slurry;
step c: and carrying out spray granulation on the second slurry to obtain the zirconium boride granulating ball.
Preferably, the mixing in step 1 is wet mixing.
Preferably, the wet-mixed solvent is ethanol, acetone, butanone or methanol.
More preferably, the wet-mixed solvent is acetone at a pH of 10.5 or ethanol at a pH of 10.5.
Preferably, the temperature rise rate of the spark plasma sintering in the step 2 is 50-200 ℃/min.
More preferably, the temperature increase rate of the spark plasma sintering in the step 2 is 100 ℃/min.
Preferably, the holding time of the spark plasma sintering in the step 2 is 15 s-35 s.
More preferably, the holding time of the spark plasma sintering in the step 2 is 15s, 30s or 35 s.
Preferably, the temperature of the spark plasma sintering in the step 2 is 1000-1400 ℃.
More preferably, the temperature of the spark plasma sintering in step 2 is 1000 ℃, 1050 ℃, 1200 ℃ or 1400 ℃.
Preferably, the peak value of the external electric field intensity of the spark plasma sintering in the step 2 is 50V/cm-200V/cm.
More preferably, the peak value of the applied electric field intensity of the spark plasma sintering in the step 2 is 50V/cm, 100V/cm, 150V/cm or 200V/cm.
The invention also provides zirconium boride-based ceramic prepared by the preparation method of the zirconium boride-based ceramic.
According to the preparation method of the zirconium boride-based ceramic, the nanometer zirconium dioxide powder is wrapped around the micron zirconium boride granulating ball through the mixed materials to be connected into a three-dimensional network structure. The resistance of the zirconium dioxide of the ionic conductor decreases as the temperature increases, so that at a constant electric field strength, the joule heating effect at the grain boundary increases to generate more heat energy. In addition, the flash firing temperature threshold of zirconium boride is lower than that of ion conductor zirconium dioxide, the zirconium dioxide can generate joule heat at lower temperature through a three-dimensional network structure, so that the temperature of zirconium boride-zirconium dioxide composite powder is far higher than that in a furnace, and diffusion effect generated by the action of an electric field is combined, so that zirconium boride-based ceramic is sinteredAnd (4) a dense effect. The zirconium boride-based ceramic prepared by the method has the relative density of over 75 percent, the Vickers hardness of over 14GP and the bending strength of over 2.0MPam1/2The zirconium boride-based ceramic prepared by the preparation method has good compactness and mechanical property.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
The zirconium boride-based ceramic and the preparation method thereof provided by the present invention are further described below.
Example 1
Step 1: adding diammonium citrate, urea and ammonia water into deionized water, adjusting pH to 9.5, magnetically stirring at 500 rpm for 3 hr, and adding zirconium boride (ZrB)2) Stirring the powder for 2 hours, and then adding silicon nitride (Si)3N4) The balls were ball milled at a rotational speed of 300 r/min. Adding a proper amount of polyvinyl butyral (PVB) binder after 24 hours, ball-milling for 24 hours, and preparing ZrB with the particle size of about 50 microns by using ball-milled slurry through spray granulation equipment2And (4) granulating the pellets.
Step 2: ZrB with a volume ratio of 4:12Prilling ball and zirconium dioxide (ZrO)2) Dissolving the powder in acetone, ball milling for 8 hr in a roller ball mill without ball milling medium to obtain ZrB2The surface of the granulation ball is coated with a layer of ZrO2The powder is subjected to rotary evaporation and drying to obtain uniformly mixed ZrB2-ZrO2Mixing the powder. Reacting ZrB2-ZrO2Putting the mixed powder into a glue discharging furnace, heating to 600 ℃ at the heating rate of 5 ℃/min, and preserving the heat for 1 h.
And step 3: and (3) putting the powder sample after the binder removal into a discharge plasma sintering furnace, putting a metal platinum sheet between the graphite pressure head and the sample as an electrode, and applying an electric field to the sample through the metal platinum sheet by an external power supply. And (3) adopting a sintering pressure of 30MPa to enable the sample and the metal platinum sheet to be always connected together in the sintering process, applying an electric field strength of 150V/cm after the temperature rises to 1050 ℃ at a heating rate of 100 ℃/min in an argon atmosphere, rapidly reducing the electric field strength after 35s, and obtaining the zirconium boride-based ceramic after the sintering process is finished.
Example 2
Step 1: adding diammonium citrate, urea and ammonia water into deionized water, adjusting the pH value to 9.5, performing magnetic stirring at the rotating speed of 500 revolutions per minute, and adding ZrB after 3 hours2Stirring the powder for 2 hours, and then adding silicon nitride (Si)3N4) The balls were ball milled at a rotational speed of 300 r/min. Adding a proper amount of polyvinyl butyral (PVB) binder after 24 hours, ball-milling for 24 hours, and preparing ZrB with the particle size of about 50 microns by using ball-milled slurry through spray granulation equipment2And (4) granulating the pellets.
Step 2: ZrB with the volume ratio of 85:152Prilling ball and zirconium dioxide (ZrO)2) Dissolving the powder in acetone with pH of 10.5, ball milling for 8 hr in a roller ball mill to obtain ZrB2The surface of the granulation ball is coated with a layer of ZrO2The powder is subjected to rotary evaporation and drying to obtain uniformly mixed ZrB2-ZrO2Mixing the powder. Reacting ZrB2-ZrO2Putting the mixed powder into a glue discharging furnace, heating to 600 ℃ at the heating rate of 5 ℃/min, and preserving the heat for 1 h.
And step 3: and (3) putting the powder sample after the binder removal into a discharge plasma sintering furnace, putting a metal platinum sheet between the graphite pressure head and the sample as an electrode, and applying an electric field to the sample through the metal platinum sheet by an external power supply. Adopting a sintering pressure of 30MPa to enable the sample and the metal platinum sheet to be always connected together in the sintering process, increasing the temperature to 1050 ℃ at a heating rate of 100 ℃/min in an argon atmosphere, applying an electric field strength of 150V/cm, rapidly reducing the electric field strength after 35s, and obtaining ZrB after the sintering process is finished2A base ceramic.
Example 3
Step 1: adding diammonium citrate to deionized waterRegulating pH value to 9.5, magnetically stirring at 500 rpm for 3 hr, adding zirconium boride (ZrB)2) Stirring the powder for 2 hours, and then adding silicon nitride (Si)3N4) The balls were ball milled at a rotational speed of 300 r/min. Adding a proper amount of polyvinyl butyral (PVB) binder after 24 hours, ball-milling for 24 hours, and preparing ZrB with the particle size of about 50 microns by using ball-milled slurry through spray granulation equipment2And (4) granulating the pellets.
Step 2: ZrB with the volume ratio of 85:152Prilling ball and zirconium dioxide (ZrO)2) Dissolving the powder in ethanol with pH of 10.5, ball milling for 8 hr in a roller ball mill without ball milling medium to obtain ZrB2The surface of the granulation ball is coated with a layer of ZrO2The powder is subjected to rotary evaporation and drying to obtain uniformly mixed ZrB2-ZrO2Mixing the powder. Reacting ZrB2-ZrO2Putting the mixed powder into a glue discharging furnace, heating to 500 ℃ at the heating rate of 5 ℃/min, and preserving the heat for 1 h.
And step 3: and (3) putting the powder sample after the binder removal into a discharge plasma sintering furnace, putting a metal platinum sheet between the graphite pressure head and the sample as an electrode, and applying an electric field to the sample through the metal platinum sheet by an external power supply. Adopting a sintering pressure of 30MPa to enable the sample and the metal platinum sheet to be always connected together in the sintering process, applying an electric field strength of 100V/cm after the temperature rises to 1200 ℃ at a heating rate of 100 ℃/min in an argon atmosphere, rapidly reducing the electric field strength after 35s, and obtaining ZrB after the sintering process is finished2A base ceramic.
Example 4
Step 1: adding diammonium citrate, urea and ammonia water into deionized water, adjusting pH to 9.5, magnetically stirring at 500 rpm for 3 hr, and adding zirconium boride (ZrB)2) Stirring the powder for 2 hours, and then adding Si3N4The balls were ball milled at a rotational speed of 300 r/min. Adding a proper amount of PVB (polyvinyl butyral) binder after 24 hours, ball-milling for 24 hours, and preparing ZrB with the grain diameter of about 50 mu m by using ball-milled slurry through spray granulation equipment2And (4) granulating the pellets.
Step 2: in a volume ratio of4:1 reaction of ZrB2Prilling ball and ZrO2Dissolving the powder in acetone with pH of 10.5, ball milling for 8 hr in a roller ball mill to obtain ZrB2The surface of the granulation ball is coated with a layer of ZrO2The powder is subjected to rotary evaporation and drying to obtain uniformly mixed ZrB2-ZrO2Mixing the powder. Reacting ZrB2-ZrO2Putting the mixed powder into a glue discharging furnace, heating to 600 ℃ at the heating rate of 5 ℃/min, and preserving the heat for 1 h.
And step 3: and (3) putting the powder sample after the binder removal into a discharge plasma sintering furnace, putting a metal platinum sheet between the graphite pressure head and the sample as an electrode, and applying an electric field to the sample through the metal platinum sheet by an external power supply. Adopting a sintering pressure of 30MPa to enable the sample and the metal platinum sheet to be always connected together in the sintering process, applying an electric field strength of 150V/cm after the temperature rises to 1400 ℃ at a heating rate of 100 ℃/min in an argon atmosphere, rapidly reducing the electric field strength after 35s, and obtaining ZrB after the sintering process is finished2A base ceramic.
Example 5
Step 1: adding diammonium citrate, urea and ammonia water into deionized water, adjusting pH to 9.5, magnetically stirring at 500 rpm for 3 hr, and adding zirconium boride (ZrB)2) Stirring the powder for 2 hours, and then adding silicon nitride (Si)3N4) The balls were ball milled at a rotational speed of 300 r/min. Adding a proper amount of polyvinyl butyral (PVB) binder after 24 hours, ball-milling for 24 hours, and preparing ZrB with the particle size of about 50 microns by using ball-milled slurry through spray granulation equipment2And (4) granulating the pellets.
Step 2: ZrB with the volume ratio of 85:152Prilling ball and zirconium dioxide (ZrO)2) Dissolving the powder in acetone with pH of 10.5, ball milling for 4 hr in a roller ball mill to obtain ZrB2The surface of the granulation ball is coated with a layer of ZrO2The powder is subjected to rotary evaporation and drying to obtain uniformly mixed ZrB2-ZrO2Mixing the powder. Reacting ZrB2-ZrO2Putting the mixed powder into a glue discharging furnace, heating to 600 ℃ at the heating rate of 5 ℃/min, and preserving the heat for 1 h.
And step 3: will discharge glueAnd putting the powder sample into a discharge plasma sintering furnace, putting a metal platinum sheet between the graphite pressure head and the sample as an electrode, and applying an electric field to the sample through the metal platinum sheet by an external power supply. Adopting a sintering pressure of 30MPa to enable the sample and the metal platinum sheet to be always connected together in the sintering process, applying an electric field strength of 50V/cm after the temperature rises to 1050 ℃ at a heating rate of 100 ℃/min in an argon atmosphere, rapidly reducing the electric field strength after 30s, and obtaining ZrB after the sintering process is finished2A base ceramic.
Example 6
Step 1: adding diammonium citrate, urea and ammonia water into deionized water, adjusting pH to 9.5, magnetically stirring at 500 rpm for 3 hr, and adding zirconium boride (ZrB)2) Stirring the powder for 2 hours, and then adding silicon nitride (Si)3N4) The balls were ball milled at a rotational speed of 300 r/min. Adding a proper amount of polyvinyl butyral (PVB) binder after 24 hours, ball-milling for 24 hours, and preparing ZrB with the particle size of about 50 microns by using ball-milled slurry through spray granulation equipment2And (4) granulating the pellets.
Step 2: ZrB with the volume ratio of 85:152Prilling ball and zirconium dioxide (ZrO)2) Dissolving the powder in acetone with pH of 10.5, ball milling for 8 hr in a roller ball mill to obtain ZrB2The surface of the granulation ball is coated with a layer of ZrO2The powder is subjected to rotary evaporation and drying to obtain uniformly mixed ZrB2-ZrO2Mixing the powder. Reacting ZrB2-ZrO2Putting the mixed powder into a glue discharging furnace, heating to 600 ℃ at the heating rate of 5 ℃/min, and preserving the heat for 1 h.
And step 3: and (3) putting the powder sample after the binder removal into a discharge plasma sintering furnace, putting a metal platinum sheet between the graphite pressure head and the sample as an electrode, and applying an electric field to the sample through the metal platinum sheet by an external power supply. Adopting a sintering pressure of 30MPa to enable the sample and the metal platinum sheet to be always connected together in the sintering process, applying an electric field strength of 200V/cm after the temperature rises to 1200 ℃ at a heating rate of 100 ℃/min in an argon atmosphere, rapidly reducing the electric field strength after 35s, and obtaining ZrB after the sintering process is finished2A base ceramic.
Example 7
Step 1: adding diammonium citrate, urea and ammonia water into deionized water, adjusting pH to 9.5, magnetically stirring at 500 rpm for 3 hr, and adding zirconium boride (ZrB)2) Stirring the powder for 2 hours, and then adding silicon nitride (Si)3N4) The balls were ball milled at a rotational speed of 300 r/min. Adding a proper amount of polyvinyl butyral (PVB) binder after 24 hours, ball-milling for 24 hours, and preparing ZrB with the particle size of about 50 microns by using ball-milled slurry through spray granulation equipment2And (4) granulating the pellets.
Step 2: ZrB with the volume ratio of 85:152Prilling ball and zirconium dioxide (ZrO)2) Dissolving the powder in ethanol with pH of 10.5, ball milling for 8 hr in a roller ball mill without ball milling medium to obtain ZrB2The surface of the granulation ball is coated with a layer of ZrO2The powder is subjected to rotary evaporation and drying to obtain uniformly mixed ZrB2-ZrO2Mixing the powder. Reacting ZrB2-ZrO2Putting the mixed powder into a glue discharging furnace, heating to 600 ℃ at the heating rate of 5 ℃/min, and preserving the heat for 1 h.
And step 3: and (3) putting the powder sample after the binder removal into a discharge plasma sintering furnace, putting a metal platinum sheet between the graphite pressure head and the sample as an electrode, and applying an electric field to the sample through the metal platinum sheet by an external power supply. Adopting a sintering pressure of 30MPa to enable the sample and the metal platinum sheet to be always connected together in the sintering process, increasing the temperature to 1000 ℃ at a heating rate of 100 ℃/min in an argon atmosphere, applying an electric field strength of 150V/cm, rapidly reducing the electric field strength after 30s, and obtaining ZrB after the sintering process is finished2A base ceramic.
Example 8
Step 1: adding diammonium citrate, urea and ammonia water into deionized water, adjusting pH to 9.5, magnetically stirring at 500 rpm for 3 hr, and adding zirconium boride (ZrB)2) Stirring the powder for 2 hours, and then adding silicon nitride (Si)3N4) The balls were ball milled at a rotational speed of 300 r/min. Adding a proper amount of polyvinyl butyral (PVB) binder after 24 hours, ball-milling for 24 hours, and spraying the ball-milled slurryA grain device for preparing ZrB with grain diameter of about 50 μm2And (4) granulating the pellets.
Step 2: ZrB with the volume ratio of 85:152Prilling ball and zirconium dioxide (ZrO)2) Dissolving the powder in acetone with pH of 10.5, ball milling for 12 hr in a roller ball mill without ball milling medium to obtain ZrB2The surface of the granulation ball is coated with a layer of ZrO2The powder is subjected to rotary evaporation and drying to obtain uniformly mixed ZrB2-ZrO2Mixing the powder. Reacting ZrB2-ZrO2Putting the mixed powder into a glue discharging furnace, heating to 550 ℃ at the heating rate of 5 ℃/min, and preserving the heat for 1 h.
And step 3: and (3) putting the powder sample after the binder removal into a discharge plasma sintering furnace, putting a metal platinum sheet between the graphite pressure head and the sample as an electrode, and applying an electric field to the sample through the metal platinum sheet by an external power supply. Adopting a sintering pressure of 30MPa to enable the sample and the metal platinum sheet to be always connected together in the sintering process, applying an electric field strength of 150V/cm after the temperature rises to 1050 ℃ at a heating rate of 100 ℃/min in an argon atmosphere, rapidly reducing the electric field strength after 15s, and obtaining ZrB after the sintering process is finished2A base ceramic.
Comparative example 1
Step 1: adding diammonium citrate, urea and ammonia water into deionized water, adjusting pH to 9.5, magnetically stirring at 500 rpm for 3 hr, and adding zirconium boride (ZrB)2) Stirring the powder for 2 hours, and then adding silicon nitride (Si)3N4) The balls were ball milled at a rotational speed of 300 r/min. Adding a proper amount of polyvinyl butyral (PVB) binder after 24 hours, ball-milling for 24 hours, and preparing ZrB with the particle size of about 50 microns by using ball-milled slurry through spray granulation equipment2And (4) granulating the pellets.
Step 2: ZrB with the volume ratio of 85:152Prilling ball and ZrO2Dissolving the powder in ethanol, ball milling for 8h in a roller ball mill without a ball milling medium to ensure that ZrB2The surface of the granulation ball is coated with a layer of ZrO2The powder is subjected to rotary evaporation and drying to obtain uniformly mixed ZrB2-ZrO2Mixing the powder. Reacting ZrB2-ZrO2Discharging the mixed powderIn the rubber oven, the temperature is raised to 500 ℃ at the heating rate of 5 ℃/min, and the temperature is kept for 1 h.
Step 3: and (3) putting the powder sample after the binder removal into a discharge plasma sintering furnace, putting a metal platinum sheet between the graphite pressure head and the sample as an electrode, and applying an electric field to the sample through the metal platinum sheet by an external power supply. And (3) adopting a sintering pressure of 30MPa to enable the sample and the metal platinum sheet to be always connected together in the sintering process, applying an electric field strength of 100V/cm after the temperature rises to 850 ℃ at a heating rate of 100 ℃/min in an argon atmosphere, and rapidly reducing the electric field strength after 5s, wherein the sintering atmosphere in the whole process is argon.
Comparative example 2
Step 1: adding diammonium citrate, urea and ammonia water into deionized water, adjusting the pH value to 9.5, performing magnetic stirring at the rotating speed of 500 revolutions per minute, and adding ZrB after 3 hours2Stirring the powder for 2 hours, and then adding silicon nitride (Si)3N4) The balls were ball milled at a rotational speed of 300 r/min. Adding a proper amount of polyvinyl butyral (PVB) binder after 24 hours, ball-milling for 24 hours, and preparing ZrB with the particle size of about 50 microns by using ball-milled slurry through spray granulation equipment2And (4) granulating the pellets.
Step 2: ZrB with the volume ratio of 95:52Prilling ball and zirconium dioxide (ZrO)2) Dissolving the powder in acetone with pH of 10.5, ball milling for 12 hr in a roller ball mill without ball milling medium to obtain ZrB2The surface of the granulation ball is coated with a layer of ZrO2The powder is subjected to rotary evaporation and drying to obtain uniformly mixed ZrB2-ZrO2Mixing the powder. Reacting ZrB2-ZrO2Putting the mixed powder into a glue discharging furnace, heating to 600 ℃ at the heating rate of 5 ℃/min, and preserving the heat for 1 h.
And step 3: and (3) putting the powder sample after the binder removal into a discharge plasma sintering furnace, putting a metal platinum sheet between the graphite pressure head and the sample as an electrode, and applying an electric field to the sample through the metal platinum sheet by an external power supply. And (3) adopting a sintering pressure of 30MPa to enable the sample and the metal platinum sheet to be always connected together in the sintering process, applying an electric field strength of 50V/cm after the temperature rises to 1050 ℃ at a heating rate of 100 ℃/min in an argon atmosphere, and rapidly reducing the electric field strength after 5s, wherein the sintering atmosphere in the whole process is argon.
Comparative example 3
Step 1: adding diammonium citrate, urea and ammonia water into deionized water, adjusting pH value to 9.5, magnetically stirring at 500 rpm for 3 hr, and adding ZrB2Stirring the powder for 2 hours, and then adding silicon nitride (Si)3N4) The balls were ball milled at a rotational speed of 300 r/min. Adding a proper amount of PVB (polyvinyl butyral) binder after 24 hours, ball-milling for 24 hours, and preparing ZrB with the grain diameter of about 50 mu m by using ball-milled slurry through spray granulation equipment2And (4) granulating the pellets.
Step 2: reacting ZrB2Putting the powder into a glue discharging furnace, heating to 600 ℃ at the heating rate of 5 ℃/min, and preserving the heat for 1 h.
And step 3: and (3) putting the powder sample after the binder removal into a discharge plasma sintering furnace, putting a metal platinum sheet between the graphite pressure head and the sample as an electrode, and applying an electric field to the sample through the metal platinum sheet by an external power supply. Adopting a sintering pressure of 30MPa to enable the sample and the metal platinum sheet to be always connected together in the sintering process, increasing the temperature to 1050 ℃ at a heating rate of 100 ℃/min in an argon atmosphere, applying an electric field strength of 150V/cm, rapidly reducing the electric field strength after 35s, and obtaining ZrB after the sintering process is finished2A base ceramic.
Comparative example 4
Step 1: adding diammonium citrate, urea and ammonia water into deionized water, adjusting pH value to 9.5, magnetically stirring at 500 rpm for 3 hr, and adding ZrB2Stirring the powder for 2 hours, and then adding silicon nitride (Si)3N4) The balls were ball milled at a rotational speed of 300 r/min. Adding a proper amount of PVB (polyvinyl butyral) binder after 24 hours, ball-milling for 24 hours, and preparing ZrB with the grain diameter of about 50 mu m by using ball-milled slurry through spray granulation equipment2And (4) granulating the pellets.
Step 2: reacting ZrB2Putting the powder into a glue discharging furnace, heating to 600 ℃ at the heating rate of 5 ℃/min, and preserving the heat for 1 h.
And step 3: loading the powder sample after binder removal into a discharge plasma sintering furnace, and placing a graphite pressure head and the sampleA metal platinum sheet is placed between the two electrodes as an electrode, and an external power supply applies an electric field to the sample through the metal platinum sheet. Adopting a sintering pressure of 30MPa to enable the sample and the metal platinum sheet to be always connected together in the sintering process, increasing the temperature to 1850 ℃ at a heating rate of 100 ℃/min in an argon atmosphere, applying an electric field strength of 150V/cm, rapidly reducing the electric field strength after 35s, and obtaining ZrB after the sintering process is finished2A base ceramic.
In summary, ZrB prepared in examples 1 to 8 and comparative examples 1 to 42The properties of the base ceramics are shown in Table 1
TABLE 1 ZrB prepared in examples 1 to 8 and comparative examples 1 to 42Properties of the base ceramic
As can be seen from Table 1, ZrB prepared in examples 1 to 82The relative density of the base ceramic reaches over 75 percent, and the compactness of the base ceramic is far stronger than that of ZrB prepared in comparative examples 1-32ZrB based ceramic and produced by sintering at high temperature with comparative example 42The density of the base ceramic has little difference. The higher the density, the fewer holes and defects in the ceramic, and the better the mechanical properties.
In addition, comparative example 1 and comparative example 2 used shorter time for spark plasma sintering, and comparative example 3 used ZrB alone2Sintering the powder to obtain ZrB prepared in comparative examples 1-32The base ceramic is not sintered completely, the density is below 70%, and the grain size of the ceramic is compared with that of ZrB prepared in examples 1-8 because the ceramic in comparative examples 1-3 is not sintered completely and is dense2The base ceramic is small. While examples 1-8 are compared to comparative example 4, comparative example 4 produced ZrB despite the traditional high temperature sintering process2The Vickers hardness and the bending strength of the base ceramic are slightly less than those of ZrB prepared in examples 1 to 82A base ceramic. Therefore, the method can quickly prepare ZrB without adopting high-temperature conditions2Based on ceramics and still have excellent mechanical properties such as hardness, bending strength and fracture toughness, and can be widely appliedThe method is used in the fields of heating elements, aerospace devices and the like.
The above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.