阅读说明：本技术 一种晶簇型无机结合剂及其制备方法 (Cluster type inorganic bonding agent and preparation method thereof ) 是由 谢德龙 潘晓毅 林峰 肖乐银 陈超 陈家荣 莫培程 于 2020-12-23 设计创作，主要内容包括：本发明公开了一种晶簇型无机结合剂及其制备方法,该结合剂按重量百分比计,由以下组分制成：SiO-220～60wt％、Al-2O-35～23wt％、B-2O-35～15wt％、K-2O 1～5wt％、Li-2O 1～8wt％、Na-2O 0～8wt％、ZnO 1～4wt％、BaO 0～5wt％、MgO 0～5wt％、晶簇成核剂1～7wt％。本发明在熔炼过程中利用先在高温下熔炼再急速降温至相对较低的温度下保温一段时间再水淬的过冷条件使熔融态材料成核,形成大量微小的形核点,再结合阶梯式升温的烧结过程使硅酸盐氧阴离子基团沉积、堆垛在形核点上,形成类似络合型的“晶簇”结构,从而实现微晶玻璃的增强增韧。(The invention discloses a crystal cluster type inorganic bonding agent and a preparation method thereof, wherein the bonding agent is prepared from the following components in percentage by weight: SiO 2 2 20～60wt％、Al 2 O 3 5～23wt％、B 2 O 3 5～15wt％、K 2 O 1～5wt％、Li 2 O 1～8wt％、Na 2 0-8 wt% of O, 1-4 wt% of ZnO, 0-5 wt% of BaO, 0-5 wt% of MgO and 1-7 wt% of a cluster nucleating agent. In the smelting process, the molten material is nucleated to form a large number of micro nucleation points by utilizing the supercooling condition that the molten material is firstly smelted at a high temperature, then rapidly cooled to a relatively low temperature, kept warm for a period of time and then quenched by water, and then the silicate oxygen is combined with the sintering process of stepped temperature rise to ensure that the silicate oxygen is oxidizedAnion groups are deposited and stacked on nucleation points to form a complex-type 'crystal cluster' structure, so that the reinforcement and toughening of the glass ceramics are realized.)

1. A cluster type inorganic bonding agent is prepared from the following components in percentage by weight:

SiO₂ 20～60wt％、Al₂O₃ 5～23wt％、B₂O₃ 5～15wt％、K₂O 1～5wt％、Li₂O 1～8wt％、Na₂0-8 wt% of O, 1-4 wt% of ZnO, 0-5 wt% of BaO, 0-5 wt% of MgO and 1-7 wt% of a cluster nucleating agent.

2. The inorganic binder of claim 1, wherein the nucleating agent is selected from ZrO₂、TiO₂And P₂O₅One or a combination of two or more of them.

3. The preparation method of the cluster type inorganic bonding agent according to claim 1, characterized in that, the components are weighed according to the formula, mixed evenly and smelted, then water quenched and ball milled, and the obtained material is sintered to obtain the cluster type inorganic bonding agent; wherein:

the smelting process comprises the following steps: firstly heating to 1350-1600 ℃, preserving heat for 60-180 min, then cooling to 1200-1480 ℃, and preserving heat for 30-60 min;

the sintering process comprises the following steps: the temperature is increased to 80-120 ℃ and is preserved for 30-180 min, then the temperature is increased to 200-300 ℃ and is preserved for 10-180 min, then the temperature is increased to 600-700 ℃ and is preserved for 60-120 min, and then the temperature is increased to 700-850 ℃ and is preserved for 90-240 min.

4. The method according to claim 3, wherein the temperature is raised to 1350-1600 ℃ at a rate of 3-10 ℃/min during the melting process, and then lowered to 1200-1480 ℃ at a rate greater than the temperature at the time of temperature raising.

5. The method according to claim 3 or 4, wherein the temperature is increased to 1200-1480 ℃ at a rate of 5-15 ℃/min during the melting process.

6. The method according to claim 3 or 4, wherein the temperature rise rate in each stage is controlled to 1 to 5 ℃/min in the sintering process.

Technical Field

The invention relates to a superhard material bonding agent, in particular to a crystal cluster type inorganic bonding agent and a preparation method thereof.

Background

The superhard material grinding tool is a grinding tool with a certain shape and strength, which is prepared by using diamond or cubic boron nitride as abrasive particles and by using a bonding agent such as metal, ceramic inorganic substance or resin. Compared with metal bonding agents and resin bonding agents, the ceramic inorganic bonding agent product has the outstanding advantages of high processing efficiency, good shape retention, strong self-sharpening property, good high-temperature stability and the like, and is widely applied to the field of grinding processing.

In the current ceramic inorganic bond superhard abrasive tool, the main component of the general ceramic bond is glass. Because the glass is a brittle material and has poor strength, the integral strength of the superhard grinding block used as a bonding agent is insufficient, the superhard grinding block cannot completely meet the requirement of high-speed and ultrahigh-speed grinding, and the glass is easy to soften, the sintering process must be strictly controlled in the sintering process, otherwise the deformation of the sintered block is easily caused, and the integral quality of the grinding tool is influenced. The superhard abrasive tool also partially uses a microcrystalline glass bonding agent, grains are separated out through a later sintering process and are used for strengthening the performance of the abrasive tool, and the separation amount and the grain size of the superhard abrasive tool have large influence on the performance of the abrasive tool.

The invention patent with publication number CN106219983A discloses a microcrystalline glass bonding agent with low sintering temperature, which specifically comprises the following components in percentage by mass: SiO 2₂ 50～70％，B₂O₃ 3～10％，Al₂O₃ 10～25％，Na₂O 0.5～5％，MgO 2～8％，Li₂O 1～10％，ZrO₂ 1～5％，TiO₂ 1～5％，La₂O₃ 1～3％，Sb₂O₃1-3%; the preparation method comprises the following steps: 1) mixing the raw materials, melting at 1200-1400 ℃, and performing water quenching, drying and grinding to obtain glass powder; 2) sintering and crystallizing the obtained glass powder at 830-850 ℃ to obtain microcrystalline glass powder; 3) and (3) carrying out high-energy ball milling on the obtained glass-ceramic powder (the rotating speed is not lower than 1200r/min, and the time is not lower than 75min) to obtain the glass-ceramic bonding agent. The sintering temperature of the adhesive is reduced by adjusting the formula and combining the method of integrally preparing the microcrystalline glass and then preparing the microcrystalline glass bonding agent by high-energy ball milling, and the sintered microcrystalline glass bonding agent has higher bending strength, wherein the bending strength is about 62MPa when the sintered microcrystalline glass is sintered at 850 ℃ as shown in figure 8. However, the invention needs to add a high-energy ball milling procedure after sintering, and has complex process and high energy consumption.

Disclosure of Invention

The invention aims to solve the technical problem of providing a cluster type inorganic bonding agent with simple process and high self bending strength and a preparation method thereof.

In order to solve the technical problems, the invention adopts the following technical scheme:

a cluster type inorganic bonding agent is prepared from the following components in percentage by weight:

SiO₂ 20～60wt％、Al₂O₃ 5～23wt％、B₂O₃ 5～15wt％、K₂O 1～5wt％、Li₂O 1～8wt％、Na₂0-8 wt% of O, 1-4 wt% of ZnO, 0-5 wt% of BaO, 0-5 wt% of MgO and 1-7 wt% of a cluster nucleating agent.

In the formula of the cluster type inorganic bonding agent, SiO₂As matrix network formers in the formulation, except for SiO₂And the components except the cluster nucleating agent are modified components, namely SiO₂The sum of the total amount of the modifying component and the cluster nucleating agent is 100 percent. The crystal cluster nucleating agent is selected conventionally in the prior art, and can be selected from ZrO₂、TiO₂And P₂O₅One or a combination of more than two of the components in any proportion.

The proportion of the components is preferably as follows:

SiO₂ 25～40wt％、Al₂O₃ 15～23wt％、B₂O₃ 8～12wt％、K₂O 1～2wt％、Li₂O 3～6wt％、Na₂3-5 wt% of O, 2-4 wt% of ZnO, 2-4 wt% of BaO, 1-3 wt% of MgO and 3-6 wt% of a cluster nucleating agent.

The preparation method of the cluster type inorganic bonding agent comprises the following steps: weighing the components according to a formula, uniformly mixing, smelting, performing water quenching and ball milling, and sintering the obtained material to obtain the cluster type inorganic bonding agent; wherein:

the smelting process comprises the following steps: firstly heating to 1350-1600 ℃, preserving heat for 60-180 min, then cooling to 1200-1480 ℃, and preserving heat for 30-60 min;

the sintering process comprises the following steps: the temperature is increased to 80-120 ℃ and is preserved for 30-180 min, then the temperature is increased to 200-300 ℃ and is preserved for 10-180 min, then the temperature is increased to 600-700 ℃ and is preserved for 60-120 min, and then the temperature is increased to 700-850 ℃ and is preserved for 90-240 min.

In the smelting process of the preparation method, the temperature is preferably raised to 1350-1600 ℃ at the speed of 3-10 ℃/min, and then is lowered to 1200-1480 ℃ at the speed of being higher than the temperature when being raised. Further preferably, the temperature is controlled to 1200 to 1480 ℃ at a rate of 5 to 15 ℃/min.

In the sintering process of the preparation method, the heating rate of each stage is preferably controlled to be 1-5 ℃/min.

In the preparation method, the materials are directly subjected to ball milling after water quenching is finished, and the particle size range of the water quenching bonding agent obtained after ball milling is preferably controlled to be 0.01-50 mu m.

When the adhesive is applied to a superhard material grinding tool, the proportion of the adhesive to superhard grinding materials (diamond or cubic boron nitride and the like) is the same as that of the superhard grinding materials in the prior art, and is usually 24-35 wt%: 65 to 76 wt%. The sintering process adopted when the superhard material grinding tool is prepared after the adhesive and the superhard grinding material are uniformly mixed is consistent with the sintering process of the adhesive.

Compared with the prior art, in the smelting process, the invention utilizes the supercooling condition of firstly smelting at high temperature, then rapidly cooling to relatively lower temperature, preserving heat for a period of time and then water quenching to nucleate the molten material to form a large number of tiny nucleation points, and then combines the subsequent sintering process of stepwise temperature rise to deposit and stack the silicate oxyanion groups on the nucleation points to form a complex-type 'crystal cluster' structure, thereby realizing the reinforcement and toughening of the microcrystalline glass and finally obtaining the adhesive with excellent self bending strength and good holding force on the superhard abrasive material. Compared with the traditional bonding agent which is purely crystallized by means of later sintering, the bonding agent prepared by the method has the advantages of more and smaller crystal nuclei, easily controlled nucleation and grain size and the like.

Drawings

FIG. 1 is a scanning electron microscope image of a fracture of a sample obtained after sintering a bonding agent prepared in example 2 of the present invention and a commercially available brand of ceramic bonding agent, wherein (a) is a commercially available brand of ceramic bonding agent; (b) the binder prepared in example 2.

Detailed Description

The present invention will be better understood from the following detailed description of specific examples, which should not be construed as limiting the scope of the present invention.

Example 1: preparation of high-silicon inorganic binder for diamond grinding tool

The formula is as follows:

SiO₂ 60wt％、Al₂O₃ 5wt％、B₂O₃ 15wt％、K₂O 1wt％、Li₂O 1wt％、Na₂O 8wt％、ZnO 1wt％、BaO 1wt％、MgO 1wt％、ZrO₂ 4wt％、TiO₂ 3wt％。

the preparation method comprises the following steps:

grinding the raw materials respectively through a 100-mesh screen, weighing the raw materials according to the chemical ratio, stirring uniformly, then sieving through the 100-mesh screen for 3 times, finally placing the sieved raw materials in an alumina crucible, and putting the crucible in a high-temperature smelting furnace for smelting, wherein the smelting process comprises the following steps: heating to 1350 ℃ at the heating rate of 10 ℃/min, and keeping the temperature for 60 min; then reducing the temperature to 1200 ℃ at the speed of 15 ℃/min, preserving the temperature for 30min, quickly pouring the materials, quenching and ball-milling to obtain the water quenching bonding agent (50 mu m) with a certain granularity. Sintering the ball-milled materials, wherein the sintering process comprises the following steps: heating to 120 ℃ at a heating rate of 1 ℃/min, and keeping the temperature for 30 min; then heating to 200 ℃ at a heating rate of 3 ℃/min, and keeping the temperature for 10 min; then heating to 600 ℃ at the heating rate of 5 ℃/min, and keeping the temperature for 60 min; heating to 750 deg.C at a rate of 1 deg.C/min, and maintaining for 90 min; and naturally cooling along with the furnace after the heat preservation is finished, and finishing sintering to obtain the cluster type inorganic bonding agent.

The three-point tensile strength of the sintered sample block of the binder prepared in this example and a commercially available ceramic binder of a certain brand was measured, and the results are shown in table 1 below.

The adhesive prepared in the embodiment and a commercially available ceramic binder of a certain brand are mixed with diamond (80/100 meshes) according to a ratio of 30 wt%: the three-point tensile strength of the test piece obtained by mixing 70 wt% and sintering the mixture by the sintering process of this example was measured, and the results are shown in table 1 below.

Table 1:

as can be seen from Table 1, from the practical effects, the bonding agent of the present invention has significantly improved strength and ability to consolidate diamond particles after sintering.

Example 2: high-alumina inorganic binder for preparing cubic boron nitride (cBN) grinding tool

The formula is as follows:

SiO₂ 20wt％、Al₂O₃ 23wt％、B₂O₃ 15wt％、K₂O 5wt％、Li₂O 8wt％、Na₂O 8wt％、ZnO 4wt％、BaO 5wt％、MgO 5wt％、ZrO₂ 2wt％、TiO₂ 3wt％、P₂O₅、2wt％。

the preparation method comprises the following steps:

grinding the raw materials respectively through a 100-mesh screen, weighing the raw materials according to the chemical ratio, stirring uniformly, then sieving through the 100-mesh screen for 3 times, finally placing the sieved raw materials in an alumina crucible, and putting the crucible in a high-temperature smelting furnace for smelting, wherein the smelting process comprises the following steps: heating to 1600 ℃ at a heating rate of 3 ℃/min, and keeping the temperature for 180 min; then reducing the temperature to 1480 ℃ at the speed of 5 ℃/min, quickly pouring the materials after heat preservation for 60min, quenching and ball milling to obtain the water quenching bonding agent (15 mu m) with a certain granularity. Sintering the ball-milled materials, wherein the sintering process comprises the following steps: heating to 80 ℃ at a heating rate of 3 ℃/min, and keeping the temperature for 180 min; then heating to 300 ℃ at the rate of 5 ℃/min, and preserving heat for 180 min; then heating to 700 ℃ at the heating rate of 1 ℃/min, and keeping the temperature for 120 min; heating to 850 deg.C at a rate of 5 deg.C/min, and maintaining for 240 min; and naturally cooling along with the furnace after the heat preservation is finished, and finishing sintering to obtain the cluster type inorganic bonding agent.

The three-point tensile strength of the sintered sample block of the binder prepared in this example and a commercially available ceramic binder of a certain brand was measured, and the results are shown in table 2 below. The morphology of the resulting sample fractures is shown in FIG. 1. As can be seen from FIG. 1, the fracture of the sample after sintering with the common ceramic bond is smooth and compact, and only part of the round holes caused by shrinkage during sintering exist. The cluster-type binding agent forms a large number of finely distributed spot-shaped particles, which are typical cluster-type structures formed by continuous nucleation, deposition and stacking of silicate ions.

The binder prepared in this example and a commercially available ceramic binder of a certain brand were mixed with cBN grinding material (100/120 mesh) in a ratio of 30 wt%: the three-point tensile strength of the test piece obtained by mixing 70 wt% and sintering the mixture by the sintering process of this example was measured, and the results are shown in table 2 below.

Table 2:

as can be seen from Table 2, from the practical effects, the bonding agent of the present invention has significantly improved strength and ability to consolidate cBN abrasive after sintering.

Example 3: preparation of diamond tool ceramic bond for precision grinding

The formula is as follows:

SiO₂ 45wt％、Al₂O₃ 15wt％、B₂O₃ 10wt％、K₂O 1wt％、Li₂O 4wt％、Na₂O 5wt％、ZnO 4wt％、BaO 5wt％、MgO 5wt％、ZrO₂ 2wt％、TiO₂ 4wt％。

the preparation method comprises the following steps:

grinding the raw materials respectively through a 100-mesh screen, weighing the raw materials according to the chemical ratio, stirring uniformly, then sieving through the 100-mesh screen for 3 times, finally placing the sieved raw materials in an alumina crucible, and putting the crucible in a high-temperature smelting furnace for smelting, wherein the smelting process comprises the following steps: heating to 1400 ℃ at a heating rate of 5 ℃/min, and keeping the temperature for 120 min; then reducing the temperature to 1250 ℃ at the speed of 12 ℃/min, preserving the temperature for 40min, quickly pouring the materials, quenching and ball-milling to obtain the water quenching bonding agent (0.01 mu m) with a certain granularity. Sintering the ball-milled materials, wherein the sintering process comprises the following steps: heating to 100 deg.C at a rate of 2 deg.C/min, and maintaining for 50 min; then heating to 250 ℃ at the heating rate of 5 ℃/min, and keeping the temperature for 100 min; then heating to 650 ℃ at the heating rate of 3 ℃/min, and preserving heat for 80 min; heating to 730 deg.C at a rate of 5 deg.C/min, and maintaining for 120 min; and naturally cooling along with the furnace after the heat preservation is finished, and finishing sintering to obtain the cluster type inorganic bonding agent.

The three-point tensile strength of the sintered sample block of the binder prepared in this example and a commercially available ceramic binder of a certain brand was measured, and the results are shown in table 3 below.

The adhesive prepared in the embodiment and a common ceramic bonding agent of a certain brand on the market are mixed with diamond micro powder (5 mu m) according to the weight percentage of 28 percent: the three-point tensile strength of the test pieces obtained by mixing 72 wt% and sintering the mixture by the sintering process of this example was measured, and the results are shown in table 3 below.

Table 3:

as can be seen from Table 3, from the practical effects, the bonding agent of the present invention has significantly improved strength and ability to consolidate cBN abrasive after sintering.