Novel zirconium oxide toughened aluminum oxide ceramic material and preparation method thereof

Abstract

The invention provides a novel zirconium oxide toughened aluminum oxide ceramic material and a preparation method thereof, belongs to the field of electronic ceramics and manufacturing thereof, and particularly relates to a novel zirconium oxide toughened aluminum oxide (ZTA) ceramic material and a preparation method thereof. The chemical formula of the material is Al10ZrY0. 03B2xSixO17 (x is greater than or equal to 0 and less than or equal to 0.35), and the material is prepared from the following raw materials: Al2O3, ZrO2, Y2O3, B2O3 and SiO2 through a solid-phase sintering method. The composite material has the advantages of high density (the volume density is 4.2967 g / cm < 3 > and the relative density is 98.4%), high bending strength (596.6 Mpa) and high quality factor (36660GHz). A synthesis formula is improved on the basis of traditional ZTA, high density and high bending strength are guaranteed, meanwhile, high quality factors are achieved, the composite material is suitable for electronic substrates and packaging materials, the preparation method is simple, and industrial production is easy.

Description

Technical Field

[0001] The invention relates to the technical field of electronic ceramics and their manufacturing, and in particular to a novel zirconium oxide toughened aluminum oxide ceramic material and a preparation method thereof. Background Art

[0002] Electronic ceramics play a key role in global society with a wide range of applications, from terrestrial and satellite communications to integrated circuit packaging, and also have important applications in high temperature and highly corrosive working environments. Today, electronic ceramic materials are ubiquitous.

[0003] Electronic ceramics are to be used in the fields of electronic communications and packaging. They should have high mechanical strength, excellent quality factor, high temperature resistance and corrosion resistance to adapt to high-intensity working environments, improve communication efficiency and ensure high-temperature stability.

[0004] Among the numerous electronic ceramics, alumina ceramics have been widely studied due to their high strength and low loss characteristics, and have played an important role in the manufacture of electronic components. Among them, zirconium oxide toughened alumina (ZTA) has good microwave dielectric properties ε r ≈15, Q×f≈15000GHz, often used as electronic substrate material. By adding appropriate additives, the mechanical and dielectric properties of ZTA can be further improved. Summary of the invention

[0005] In view of the above problems, the present invention aims to improve the mechanical and electrical properties of zirconia toughened alumina, develop a high-strength, high-quality factor ceramic material, and provide a new zirconia toughened alumina ceramic material and a preparation method thereof.

[0006] The present invention adopts the following technical solutions:

[0007] A new type of zirconia toughened alumina ceramic material, the chemical formula of the material is A l 10 Yj Y 0.03 B 2x S i x O 17 (0≤x≤0.35), the raw material composition is Al 2 O 3 , ZrO 2 , Y 2 O 3 , B 2 O 3 , SiO 2 , synthesized by solid phase method; when x = 0.15, it has a high density (4.2967g / cm 3 ), high bending strength (596.6Mpa), high quality factor (36660GHz).

[0008] The specific preparation method is as follows:

[0009] Step 1: Al 2 O 3 , ZrO 2 , Y 2 O 3 , B 2 O 3 , SiO 2 The original powder is according to the chemical formula Al 10 Yj Y 0.03 B 2x Si x O 17 (0≤x≤0.35) for batching;

[0010] Step 2: Planetarily ball mill the ingredients prepared in step 1 according to the mass ratio of powder, zirconium oxide balls and ultrapure water of 1:5:1, mix for 8 hours, take out and dry at 110°C, sieve with a 200-mesh sieve, and then granulate the powder with an acrylic acid aqueous solution. After drying, sieve with a 200-mesh sieve again to ensure that the particles are fine and uniform.

[0011] Step 3: Press the obtained powder into a shape, and finally sinter it in a muffle furnace with a heating rate of 3°C / min, keep it at 450°C for one hour to drain the binder, and sinter it at 1550°C in an atmospheric atmosphere for 3 hours to obtain a new type of zirconia toughened alumina ceramic material.

[0012] The present invention makes full use of SiO 2 The high lattice energy of SiO bonds in the molten state allows the silicon-oxygen bonds to maintain local order in the molten state, forming a uniform low-melting compound, avoiding phase separation or uneven structure, and inhibiting excessive grain growth or abnormal coarsening. 2 O 3 At high temperatures, a liquid phase is formed to fill micropores and cracks and hinder grain boundary migration, thereby refining the grains and improving the overall density of the ceramic. 2 O 3 The stabilizer content is fixed at ZrO 2 The content is 3%. Finally, a new type of zirconia toughened alumina ceramic material was obtained.

[0013] The preparation method is traditional pressureless sintering, which can greatly improve the bending strength and microwave dielectric properties of ZTA under the premise of low cost and simple process, and is suitable for mass production.

[0014] In summary, the novel zirconia-toughened alumina ceramic provided by the present invention has a dense structure, high bending strength, and high quality factor, and has great prospects in the application of electronic substrate materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings of the embodiments will be briefly introduced below. Obviously, the drawings in the following description only relate to some embodiments of the present invention, but are not intended to limit the present invention.

[0016] Figure 1 for Figure 1 is the XRD diffraction pattern of Example 1-8;

[0017] Figure 2 for Figure 2 (a) to (h) correspond to the cross-sectional morphology SEM images of Examples 1-8 after the bending strength test; DETAILED DESCRIPTION

[0018] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0019] like Figure 1 to Figure 2 As shown, the present invention is described in detail below in conjunction with the accompanying drawings and embodiments.

[0020] The chemical formula of the material of the present invention is Al 10 Yj Y 0.03 B 2x S i x O 17 (0≤x≤0.35), the material is prepared by a solid phase method, and the specific steps are the same as the above steps.

[0021] The composition and microwave dielectric properties of the specific embodiments are as follows:

[0022] Table 1: Component content of ZTA samples

[0023]

[0024] Table 2: Microwave dielectric properties of ZTA samples

[0025]

[0026] From Table 1 and Table 2, we can see that as B 2 O 3 、S iO 2As the content increases, the dielectric constant of the sample increases first and then decreases, the density increases first and then decreases, and the flexural strength gradually increases and then decreases. The dielectric constant shows an overall trend of first increasing and then decreasing, while the quality factor increases first and then decreases. Overall, the best mechanical properties are obtained in Example 4. The relative density is 98.4%, and the density ρ = 4.2967g / cm 3 , flexural strength 596.6Mpa, best microwave dielectric properties ε r =15.91, Q×f=36660GHz.

[0027] XRD spectra of ZTA ceramic samples of different examples ( Figure 1 ) were analyzed and found that their phase compositions were basically the same, with the main phase composition being α-Al 2 O 3 With t-ZrO 2 , prove that adding B 2 O 3 、SiO 2 No new phase will be formed, nor will the original phase composition of the ZTA matrix change. This also proves that the new ZTA ceramic material does not rely on phase change to improve mechanical and dielectric properties.

[0028] Figure 2 (a) to (h) show the SEM microstructures of samples 1 to 8, respectively. It can be seen that in samples 1 and 2, the ZTA has relatively more pores, and obvious pores can be seen in the scanning electron microscope images (such as Figure 2 In addition, the aluminum oxide particles (bright white) are larger, 2 O 3 The particles (dark gray) agglomerated. 2 O 3 、S iO 2 With the increase of ZrO content, the pores of ZTA are reduced, the grain size is better controlled, and the 2 Evenly distributed in Al 2 O 3 In the crystal, it is proved that the silicon-oxygen bond maintains local order in the molten state, forming a uniform low-melting compound, avoiding phase separation or inhomogeneous structure, inhibiting excessive growth or abnormal coarsening of grains. It also forms a liquid phase at high temperature, filling micropores and cracks, and hindering grain boundary migration, thereby refining the grains and improving the overall density of the ceramic. 2 O 3 、S i O 2 As the content increases further, adverse effects begin to appear, and it is observed that the grain size of Sample 8 increases significantly, the number of fine and evenly distributed alumina particles decreases, and large areas of liquid phase aggregation appear on the crystal surface, which weakens the overall structural strength of the ZTA composite.

[0029] In summary, the present invention adopts the traditional pressureless sintering method to prepare the new zirconia toughened alumina ceramics, and adjusts the formula and tests the performance to obtain the best formula (Sample 4). 2 O 3 、S iO 2 Composite materials can greatly improve density, bending strength and quality factor. They are suitable for electronic packaging substrate materials, have low requirements on production conditions, and are easy to industrialize and mass-produce.

[0030] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A new type of zirconia toughened alumina ceramic material, characterized in that: The basic formula is Al2O3, ZrO2, Y2O3, B2O3, SiO2, prepared by solid phase method; density (bulk density 4.2967g / cm 3 Relative density 98.4%), flexural strength (596.6Mpa), quality factor (36660GHz).

2. The method for preparing the novel zirconia toughened alumina ceramic material according to claim 1, characterized in that: The details are as follows: Step 1: Prepare the raw powders of high-purity Al2O3, ZrO2, Y2O3, B2O3 and SiO2 according to the chemical formula Al 10 Yj Y 0.03 B 2x Si x O 17 (0≤x≤0.35) for batching; Step 2: The ingredients prepared in step 1 are subjected to planetary ball milling according to a mass ratio of powder, zirconium oxide balls and ultrapure water of 1:5:1, mixed for 8 hours, taken out and dried at 110°C, sieved with a 200-mesh sieve, and then granulated with an acrylic acid aqueous solution. After drying, the powder is sieved again with a 200-mesh sieve to ensure that the particles are fine and uniform; Step 3: Press the obtained powder into a shape, and finally sinter it in a muffle furnace with a heating rate of 3°C / min, keep it at 450°C for one hour to drain the binder, and sinter it at 1550°C in an atmospheric atmosphere for 3 hours to obtain a new type of zirconia toughened alumina ceramic material.

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