阅读说明：本技术 一种pva/cbn复合纤维磨料及用其制备的树脂砂轮 (PVA/CBN composite fiber abrasive and resin grinding wheel prepared by same ) 是由 张国威 高翀 刘民强 周少杰 于 2021-08-04 设计创作，主要内容包括：本发明属于超硬材料制品技术领域,具体涉及一种PVA/CBN复合纤维磨料及用其制备的树脂砂轮。所述PVA/CBN复合纤维磨料的制备方法为：将PVA粉末加入到水中,然后升温至60～90℃,搅拌直至溶解,制成PVA水溶液；向PVA水溶液中加入磨料,得混合溶液；用混合溶液纺丝并切割,即得PVA/CBN复合纤维磨料。本发明砂轮主要是由PVA/CBN复合纤维磨料构成,结构比较疏松,砂轮具有弹性特点,磨削时不会出现堵塞和烧伤工件现象,不会产生太多的磨削热,不易产生刮痕,应用在不同硬度工件磨削上,表面效果优良。(The invention belongs to the technical field of superhard material products, and particularly relates to a PVA/CBN composite fiber abrasive and a resin grinding wheel prepared by using the same. The preparation method of the PVA/CBN composite fiber abrasive comprises the following steps: adding PVA powder into water, heating to 60-90 ℃, and stirring until the PVA powder is dissolved to prepare a PVA aqueous solution; adding an abrasive into the PVA aqueous solution to obtain a mixed solution; and spinning and cutting the mixed solution to obtain the PVA/CBN composite fiber abrasive. The grinding wheel is mainly composed of PVA/CBN composite fiber grinding materials, is loose in structure, has the elastic characteristic, cannot block or burn workpieces during grinding, cannot generate too much grinding heat, is not easy to generate scratches, is applied to grinding of workpieces with different hardness, and has an excellent surface effect.)

1. A preparation method of a PVA/CBN composite fiber abrasive is characterized by comprising the following steps:

(1) adding PVA powder into water, heating to 60-90 ℃, and stirring until the PVA powder is dissolved to prepare a PVA aqueous solution;

(2) adding an abrasive into the PVA aqueous solution obtained in the step (1) to obtain a mixed solution;

(3) and (3) spinning and cutting the mixed solution obtained in the step (2) to obtain the PVA/CBN composite fiber abrasive.

2. The method for preparing the PVA/CBN composite fiber abrasive material according to claim 1, wherein the abrasive material in the step (2) is CBN and/or corundum.

3. The method for preparing the PVA/CBN composite fiber abrasive material according to claim 1, wherein the spinning diameter in the step (3) is 30 to 250 μm, and the cutting length is 50 to 500 μm.

4. The preparation method of the PVA/CBN composite fiber abrasive material according to claim 1, wherein the PVA powder is added in water in an amount of 0.07-0.45g/ml, and the amount of the abrasive material is 0.4-20 times the mass of the PVA powder.

5. A PVA/CBN composite fiber abrasive material prepared by the method of any one of claims 1 to 4.

6. The PVA/CBN composite fiber abrasive resin grinding wheel is characterized by comprising an abrasive layer and a base body, wherein the abrasive layer comprises the following raw materials in percentage by weight: 2-8% of phenolic resin liquid, 3-15% of epoxy resin liquid, 5-20% of phenolic resin powder, 1-20% of auxiliary material and the balance of PVA/CBN composite fiber abrasive.

7. The resinoid grinding wheel of claim 6, wherein the auxiliary material is cryolite and/or talc.

8. The method for manufacturing a resin grinding wheel according to any one of claims 6 to 7, characterized by comprising the steps of: uniformly mixing PVA/CBN composite fiber abrasive, phenolic resin liquid, epoxy resin liquid and phenolic resin powder, and then adding auxiliary materials and uniformly mixing to obtain a mixture; and (5) placing the mixture into a mold for molding and curing to obtain the grinding wheel.

9. Use of the grinding wheel according to any of claims 6 to 7 for high precision grinding and polishing of metal surfaces.

Technical Field

The invention belongs to the technical field of superhard material products, and particularly relates to a PVA/CBN composite fiber abrasive and a resin grinding wheel prepared by using the same.

Background

With the continuous improvement of the automation degree of grinding equipment and the higher and higher requirements on the surface appearance of various metal parts, people also put forward higher requirements on the precision grinding processing performance of the grinding wheel, most of the surface processing of the metal workpiece at present adopts a common corundum grinding wheel which is divided into two procedures of fine grinding and polishing, and the processing time and the processing efficiency are relatively longer. The CBN grinding material is a novel tool material which is suitable for the modern processing technical requirements, has unique and excellent cutting performance, and the grinding wheel made of the CBN grinding material is just suitable for the development of high-efficiency precision grinding. Although the CBN abrasive has excellent cutting performance, in the production process of the grinding wheel, if the design and manufacture are not good, the grinding defects of workpiece surface burning, scratch and the like caused by blockage can occur in the grinding process, or the service life of the grinding wheel is low caused by too fast threshing of the grinding wheel. In view of the above, it is important to design and manufacture a grinding wheel with excellent performance during grinding and polishing processes.

Disclosure of Invention

In order to overcome the problems in the prior art, the invention provides a preparation method of a PVA/CBN composite fiber abrasive. The PVA/CBN composite fiber abrasive is used for preparing the resin grinding wheel, so that the grinding wheel has excellent performance and higher grinding efficiency and durability, and a large amount of time cost and production cost are saved.

The invention also provides a method for preparing the resin grinding wheel by adopting the PVA/CBN composite fiber abrasive.

In order to achieve the purpose, the technical scheme of the invention is as follows:

a preparation method of a PVA/CBN composite fiber abrasive material comprises the following steps:

(1) adding PVA powder into water, soaking for 0.5-2 hours, then heating to 60-90 ℃, and stirring until the PVA powder is dissolved to prepare a PVA aqueous solution;

(2) adding an abrasive into the PVA aqueous solution obtained in the step (1) to obtain a mixed solution;

(3) and (3) spinning and cutting the mixed solution obtained in the step (2) to obtain the PVA/CBN composite fiber abrasive.

Preferably, the abrasive in step (2) is CBN and/or corundum.

Preferably, the spinning diameter of step (3) is 30-250 μm, and the cutting length is 50-500. mu.m.

Preferably, the addition amount of the PVA powder in water is 0.07-0.45g/ml, and the using amount of the grinding material is 0.4-20 times of the mass of the PVA powder.

The invention provides a PVA/CBN composite fiber abrasive prepared by the method.

A PVA/CBN composite fiber abrasive resin grinding wheel is composed of an abrasive layer and a base body, wherein the abrasive layer comprises the following raw materials in percentage by weight: 2-8% of phenolic resin liquid, 3-15% of epoxy resin liquid, 5-20% of phenolic resin powder, 1-20% of auxiliary material and the balance of PVA/CBN composite fiber abrasive.

Preferably, the auxiliary material is cryolite and/or talcum powder.

The invention provides a preparation method of the resin grinding wheel, which comprises the following steps: firstly, adding PVA/CBN composite fiber abrasive into phenolic resin liquid and epoxy resin liquid, uniformly mixing, then uniformly mixing phenolic resin powder and auxiliary materials, and uniformly mixing the phenolic resin powder and the auxiliary materials to obtain a molding material; and (3) placing the molding material into a mold for molding and curing (curing at 130-160 ℃ for 3-10 h) to obtain the PVA/CBN composite fiber abrasive resin grinding wheel.

Preferably, the mixture is poured into a grinding wheel die to be pressed and molded in the molding process, and the molding density is 0.82-1.96g/cm³(ii) a The maximum curing temperature is 130-160 ℃, and the curing time is 3-12h, so that the PVA/CBN composite fiber abrasive resin grinding wheel is prepared.

The grinding wheel is used for high-efficiency precise grinding and polishing of metal surfaces, namely for high-precision grinding and polishing of metal surfaces.

In the present invention, each PVA/CBN composite fiber abrasive contains a plurality of small CBN abrasive grains and/or corundum under the binding action of PVA. After the grinding wheel is made, the fiber grinding materials are mutually overlapped under the action of the resin bonding agent to form a nest-shaped structure, the whole composite grinding material is not easy to fall off when the grinding force is applied, and CBN single grinding material particles gradually fall off under the action of the grinding force, so that the service life of the grinding wheel is prolonged, and meanwhile, the grinding wheel is very sharp during grinding due to the fluffy structure of the grinding wheel, so that the grinding efficiency of the grinding wheel is improved.

Compared with the prior art, the invention has the beneficial effects that:

1) the grinding wheel abrasive layer is mainly composed of PVA/CBN composite fiber abrasives, so that the prepared grinding wheel is loose in structure and has the elastic characteristic, the phenomena of blockage and workpiece burning cannot occur during workpiece grinding, too much grinding heat cannot be generated, scratches cannot be easily generated on the surface of the workpiece, and the excellent grinding/polishing effect is shown;

2) the grinding wheel can continuously grind for a long time, two procedures of fine grinding and polishing can be replaced in the automatic grinding process, grinding with larger allowance is carried out, and the surface brightness of a workpiece is far superior to the effect which can be achieved by a common polishing grinding wheel;

3) the grinding wheel prepared by the invention has higher grinding efficiency and durability, and saves a large amount of time cost and production cost, thereby improving the economic benefit.

Drawings

FIG. 1 is a PVA/CBN composite fiber abrasive prepared in example 1; as can be seen in fig. 1: each PVA/CBN composite fiber abrasive comprises a plurality of small-particle CBN abrasives;

FIG. 2 is a microscopic morphology of the PVA/CBN composite fiber abrasive wheel prepared in example 1; as can be seen from fig. 2: a plurality of PVA/CBN composite fiber abrasives are mutually lapped to form a nest-shaped structure, and each fiber abrasive is more firmly lapped by the binding agent;

FIG. 3 is a schematic structural diagram of a PVA/CBN composite fiber abrasive grinding wheel. In the figure, 1 is an abrasive layer, and 2 is a grinding wheel base.

Detailed Description

The invention is further illustrated, but not limited, by the following examples and the accompanying drawings.

It should be noted that: the degree of polymerization of PVA powder used in the invention is 800-2600, and the degree of alcoholysis is 80-92; the granularity of the CBN abrasive is M36/54-M0.5/1.5, and is referred to as JB T7990-2012; the granularity of the corundum abrasive is F400-F2000, and the reference standard GB/T2481.2-2020; are all common commercial products or can be prepared by adopting the conventional technology in the field.

Phenolic resin liquid: product model PF-2551, New Material Ltd of Shandong Shengquan,

epoxy resin liquid: product model E44, Gallery Nolnogon chemical Co., Ltd,

phenolic resin powder: product model No. PF-2802A, santa americana new materials gmbh.

Example 1

The preparation method of the PVA/CBN composite fiber abrasive material comprises the following steps:

(1) adding 15g of PVA powder into 100ml of water, soaking for 1 hour, then heating to 60 ℃, and stirring until the PVA powder is dissolved to prepare a PVA aqueous solution;

(2) adding 80g of CBN abrasive micropowder with the granularity of M20/30 and 10g of F600 corundum micropowder into the PVA aqueous solution obtained in the step (1), and uniformly stirring to obtain a mixed solution;

(3) and (3) spinning by using the mixed solution obtained in the step (2) (the mixed solution is uniformly stirred by using a stirrer to prepare a colloid mixed suspension, then spinning the colloid mixed suspension into filaments by using spinning equipment, and controlling the spinning diameter through the pore diameters of different spinneret plates, which is realized by adopting the conventional technology in the field, and is not repeated because the conventional technology is not the innovation of the application, the spinning diameter is 180 mu m, and the prepared filaments are cut into short filaments with the length of 450 mu m, so that the PVA/CBN composite fiber abrasive material (see figure 1) is obtained.

The resin grinding wheel prepared from the PVA/CBN composite fiber abrasive comprises an abrasive layer and a base body, wherein the abrasive layer comprises the following raw materials in percentage by weight: 2% of phenolic resin liquid, 3% of epoxy resin liquid, 10% of phenolic resin powder, 3% of cryolite and the balance of PVA/CBN composite fiber abrasive.

The preparation method of the resin grinding wheel comprises the following steps: according to the formula, the PVA/CBN composite fiber abrasive is added into the phenolic resin liquid and the epoxy resin liquid to be uniformly mixed, then the phenolic resin powder and the cryolite powder are uniformly mixed, and then the phenolic resin powder and the cryolite powder are uniformly mixed to obtain a molding material; pouring the molding material into a grinding wheel die to be strickled off and pressed for molding, wherein the molding density is 1.76g/cm³(ii) a The maximum curing temperature is 160 ℃, the curing time is 3 hours, and the PVA/CBN composite fiber abrasive resin grinding wheel is prepared (see figures 2 and 3).

Example 2

The preparation method of the PVA/CBN composite fiber abrasive material comprises the following steps:

(1) adding 30g of PVA powder into 100ml of water, soaking for 1 hour, then heating to 75 ℃, and stirring until the PVA powder is dissolved to prepare a PVA aqueous solution;

(2) adding 50g of CBN abrasive micropowder with the granularity of M8/12 and 1g of corundum micropowder with the granularity of F1000 into the PVA aqueous solution obtained in the step (1), and uniformly stirring to obtain a mixed solution;

(3) and (3) spinning by using the mixed solution obtained in the step (2), wherein the spinning diameter is 80 microns, and cutting the prepared filaments into short filaments with the length of 400 microns to obtain the PVA/CBN composite fiber abrasive.

The resin grinding wheel prepared from the PVA/CBN composite fiber abrasive comprises an abrasive layer and a base body, wherein the abrasive layer comprises the following raw materials in percentage by weight: 6% of phenolic resin liquid, 10% of epoxy resin liquid, 16% of phenolic resin powder, 16% of talcum powder and the balance of PVA/CBN composite fiber abrasive.

The preparation method of the resin grinding wheel comprises the following steps: according to the formula, the PVA/CBN composite fiber abrasive is added into the phenolic resin liquid and the epoxy resin liquid to be uniformly mixed, then the phenolic resin powder and the talcum powder are uniformly mixed, and then the phenolic resin powder and the talcum powder are uniformly mixed to obtain a molding material; pouring the mixture into a grinding wheel die, strickling and pressing for molding, wherein the molding density is 1.49g/cm³(ii) a The highest curing temperature is 150 ℃, and the curing time is 6 hours, so that the PVA/CBN composite fiber abrasive resin grinding wheel is prepared.

Example 3

The preparation method of the PVA/CBN composite fiber abrasive material comprises the following steps:

(1) adding 10g of PVA powder into 100ml of water, heating to 85 ℃, and stirring until the PVA powder is dissolved to prepare a PVA aqueous solution;

(2) adding 120g of abrasive CBN micro powder with the granularity of M2/4 and 20g of corundum micro powder with the granularity of F1500 into the PVA aqueous solution obtained in the step (1), and uniformly stirring to obtain a mixed solution;

(3) and (3) spinning by using the mixed solution obtained in the step (2), wherein the spinning diameter is 40 mu m, and cutting the prepared filaments into short filaments with the length of 100 mu m to obtain the PVA/CBN composite fiber abrasive.

The resin grinding wheel prepared from the PVA/CBN composite fiber abrasive comprises an abrasive layer and a base body, wherein the abrasive layer comprises the following raw materials in percentage by weight: 4% of phenolic resin liquid, 7% of epoxy resin liquid, 8% of phenolic resin powder, 10% of talcum powder and the balance of PVA/CBN composite fiber abrasive.

The preparation method of the resin grinding wheel comprises the following steps: according to the formula, the PVA/CBN composite fiber abrasive is added into the phenolic resin liquid and the epoxy resin liquid to be uniformly mixed, then the phenolic resin powder and the talcum powder are uniformly mixed, and then the phenolic resin powder and the talcum powder are uniformly mixed to obtain a molding material; pouring the mixture into a grinding wheel die to be strickled and pressed for molding, wherein the molding density is 1.0g/cm³(ii) a The maximum curing temperature is 130 ℃, the curing time is 10 hours, and the PVA/CBN composite fiber abrasive resin grinding wheel is prepared.

Comparative example 1

The grinding wheel of this comparative example differs from the grinding wheel of example 1 in that: the abrasive of this comparative example did not undergo a spinning process with PVA, i.e. the grinding wheel formulation was: the abrasive layer comprises the following raw materials in percentage by weight: 11.7% of PVA powder, 2% of phenolic resin liquid, 3% of epoxy resin liquid, 10% of phenolic resin powder, 3% of cryolite powder, 62.5% of CBN micro powder as an abrasive and 7.8% of corundum micro powder (the dosage is the same as that in example 1).

Data of effect test

The results of comparison of the grinding performance of the grinding wheel of example 1 according to the invention with the grinding wheel of comparative example 1 under the same grinding conditions (grinding machine: model No. MM7120A test modified grinding machine; grinding wheel speed: 2800 rpm; workpiece material: Cr12MoV, HRC 60-62; workpiece size: length, width, thickness: 200MM, 30MM, 5 MM; grinding allowance: 0.1 MM.) are given in table 1.

TABLE 1 grinding wheel grinding test comparison

From the data in table 1, it can be seen that: in the grinding wheel with the same specification, the grinding time of the grinding wheel is reduced by 22 percent, the grinding ratio is improved by 7 percent, and the surface roughness of the ground workpiece is basically consistent, which shows that the grinding efficiency and the durability of the grinding wheel are obviously improved under the action of the bird nest structure after the PVA/CBN composite fiber grinding material is adopted.