CN116854466B

CN116854466B - Ceramic ferrule and preparation method and application thereof

Info

Publication number: CN116854466B
Application number: CN202310782164.3A
Authority: CN
Inventors: 郑镇宏
Original assignee: Deyang Sanhuan Technology Co ltd; Chengdu Sanhuan Technology Co ltd; Nanchong Three Circle Electronics Co Ltd
Current assignee: Deyang Sanhuan Technology Co ltd; Chengdu Sanhuan Technology Co ltd; Nanchong Three Circle Electronics Co Ltd
Priority date: 2023-06-28
Filing date: 2023-06-28
Publication date: 2024-03-15
Anticipated expiration: 2043-06-28
Also published as: CN116854466A

Abstract

The invention discloses a ceramic ferrule, a preparation method and application thereof, wherein the ceramic ferrule is prepared from raw materials including ceramic powder; the ceramic powder comprises 70-90% by weight of zirconia and yttria, and in an XRD spectrum, the ratio of the characteristic peak intensity of the zirconia at 2 theta = 30.2 degrees to the characteristic peak intensity of the yttria at 2 theta = 48.5 degrees is greater than 100:1. The ceramic powder with a specific structure is used for preparing the ceramic ferrule, so that the compactness and the flexural strength of the ceramic ferrule meet the index requirements, the probability of cracking and deformation is greatly reduced, meanwhile, the thermal ageing resistance is excellent, the high precision of ceramic ferrule products can be realized, and the qualified rate is improved.

Description

Ceramic ferrule and preparation method and application thereof

Technical Field

The invention relates to the technical field of ceramic photoelectric elements, in particular to a ceramic ferrule and a preparation method and application thereof.

Background

The ceramic fiber ferrule is a necessary core component for producing and manufacturing the fiber connector, is a device for detachably connecting optical fibers, precisely connects two end faces of the optical fibers, ensures that the light energy output by the transmitting optical fiber can be coupled into the receiving optical fiber to the maximum extent, and is a key component for keeping a light path smooth, small in signal loss and high in coaxiality. Therefore, ceramic ferrules with excellent performance are required as urgent requirements in the industry, and are a necessary condition for promoting network optical fibers.

Basically, the ceramic ferrule is made of zirconia fine powder as an essential raw material (usually, a small amount of yttria is added to the zirconia fine powder in order to keep the tetragonal phase with more excellent performance at room temperature), and is formed by high-pressure powder injection molding. Zirconia is a wear-resistant and corrosion-resistant ceramic material and is widely applied to the high and new technical fields of electronic ceramics, functional ceramics, structural ceramics and the like.

However, the existing ceramic ferrule obtained by taking zirconia micropowder as an essential raw material has the problems of poor ageing resistance, low coaxiality qualification rate and low flexural strength.

Disclosure of Invention

The present invention aims to solve at least one of the above technical problems in the prior art. Therefore, the invention aims to provide the ceramic ferrule, the preparation method and the application thereof, and the ceramic powder with a specific structure is used for preparing the ceramic ferrule, so that the density and the flexural strength of the ceramic ferrule meet the index requirements, the probability of cracking and deformation is greatly reduced, the thermal ageing resistance is excellent, the high precision of ceramic ferrule products can be realized, and the qualified rate is improved.

In order to achieve the above purpose, the technical scheme adopted by the invention is as follows:

in a first aspect of the present invention, a ceramic ferrule is provided, which is prepared from a raw material for preparing a ceramic powder; the ceramic powder comprises 70-90% by weight of zirconia and yttria, and in an XRD spectrum, the ratio of the characteristic peak intensity of tetragonal zirconia at 2θ=30.2 degrees to the characteristic peak intensity of yttria at 2θ=48.5 degrees is greater than 100:1.

The ratio of the characteristic peak intensity of the tetragonal zirconia at 2 theta=30.2 degrees to the characteristic peak intensity of the yttria at 2 theta=48.5 degrees is greater than 100:1, and the yttria and the zirconia form more solid solutions and are more stable, so that the prepared insert core has higher intensity and better heat aging performance. When the ratio of the characteristic peak intensity of tetragonal zirconia at 2θ=30.2° to the characteristic peak intensity of yttria at 2θ=48.5° is less than 100:1, part of the yttria does not form a solid solution with zirconia, on the one hand, the tetragonal zirconia can be deteriorated in the ability to be kept to room temperature, and on the other hand, the isolated yttria plays a role of a defect point in a crystal lattice to influence the flexural strength and the ageing resistance of the product.

In some embodiments of the invention, the ceramic ferrule is made from a manufacturing raw material comprising ceramic powder; the ceramic powder comprises zirconia and yttria, wherein in an XRD spectrum, the ratio of the characteristic peak intensity of tetragonal zirconia at 2 theta = 30.2 degrees to the characteristic peak intensity of yttria at 2 theta = 48.5 degrees is greater than 100:1.

In some embodiments of the invention, the ceramic powder has a specific surface area of 10-20m ² And/g. When the specific surface area of the ceramic powder is smaller than 10m ² At/g, the sintering activity is reduced, and the compactness at the same temperature is deteriorated; when the specific surface area of the ceramic powder is more than 20m ² And at the time of/g, the agglomeration phenomenon is easy to occur, and the flexural strength of the ceramic ferrule product is influenced.

In some embodiments of the invention, the ceramic powder has an average particle size of 0.1-0.3 μm.

In some embodiments of the invention, the ratio of D90 to D10 of the ceramic powder is controlled to be 5.0-10.0. When the ratio of D90 to D10 of the ceramic powder is smaller than 5.0, the particle size distribution is too narrow, the stacking property is not strong, gaps among large particle sizes are filled to a limited extent, the compactness is poor, and the strength of the ceramic ferrule is affected; when the ratio of D90 to D10 of the ceramic powder is more than 10.0, the particle size distribution is too wide, effective accumulation cannot be formed, the compactness is also deteriorated, and the flexural strength is reduced.

In some embodiments of the invention, the zirconia is 90-98% by weight of the ceramic powder and the yttria is 1-9% by weight of the ceramic powder.

In some preferred embodiments of the invention, the zirconia is present in an amount of 96.5% by weight of the ceramic powder and the yttria is present in an amount of 3% by weight of the ceramic powder.

In some embodiments of the invention, the ceramic powder further comprises alumina in an amount of 0.1-1% by weight of the ceramic powder.

In some preferred embodiments of the present invention, the ceramic powder further includes alumina in an amount of 0.5% by weight of the ceramic powder.

In some embodiments of the invention, the ferrule further comprises an organic additive in an amount of 10% -30% by weight.

In some embodiments of the invention, the organic aids include binders, plasticizers, dispersants, and organic macromolecular backbones.

In some embodiments of the invention, the binder is present in an amount of 5-15% by weight of the organic auxiliary.

In some embodiments of the invention, the plasticizer is present in an amount of 0-20% by weight of the organic aid.

In some embodiments of the invention, the dispersant is present in an amount of 5 to 25% by weight of the organic adjuvant.

In some embodiments of the invention, the organic macromolecular scaffold is 20-40% by weight of the organic adjuvant.

The invention adds the organic adhesive to provide a carrier for the injection molding fluidity of the powder, and simultaneously plays a role in bonding the powder, and simultaneously provides a space for the growth of ceramic grains in the sintering process through the pores formed after the glue is discharged.

In some embodiments of the invention, the binder comprises at least one of paraffin wax, polyethylene wax, polypropylene wax, ethylene vinyl acetate wax.

In some embodiments of the invention, the plasticizer comprises at least one of phthalic acid Dingzhi, dimethyl phthalate, dioctyl terephthalate, dibutyl phthalate.

In some embodiments of the invention, the dispersant comprises at least one of stearic acid, oleic acid.

In some embodiments of the invention, the organic macromolecular scaffold component comprises at least one of polymethyl methacrylate, polybutyl methacrylate, polyvinyl alcohol Ding Quanzhi, polypropylene, polystyrene, polyethylene.

In a second aspect of the present invention, a method for preparing the ceramic ferrule is provided, including the steps of:

mixing ceramic powder and an organic additive according to the weight content, mixing, granulating, injection molding, degreasing and sintering to obtain the ceramic ferrule.

In some embodiments of the invention, the temperature of the mixing is 200-300 ℃ and the time of the mixing is 2-5 hours.

In some embodiments of the invention, the temperature of the injection molding is 100-200 ℃, and the speed of the injection molding is 10-50mm/s.

In some embodiments of the invention, the degreasing temperature is 300-800 ℃ and the degreasing time is 20-50h.

In some embodiments of the invention, the sintering temperature is 1200-1500 ℃ and the sintering time is 20-40h.

In some embodiments of the invention, the injection molding peak pressure is 30-70MPa and the injection molding cycle time is 20-50s.

In a third aspect of the present invention, an optical fiber connector is provided that includes the ferrule.

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

(1) According to the invention, the specific surface area of the ceramic powder is controlled, so that the agglomeration phenomenon of the ceramic powder is avoided, and the strength of the ceramic ferrule product is obviously improved; the ratio of D90 to D10 of the ceramic powder is controlled, so that the large-particle-size powder and the small-particle-size powder of the ceramic powder are alternately stacked, the small-particle-size powder is just filled in the gaps of the large-particle-size powder, the stacking property and compactness are enhanced, and the strength of the ceramic ferrule reaches the maximum value; the common control of the specific surface area and the particle size distribution obviously improves the flexural strength of the ceramic ferrule.

(2) The 2 theta characteristic peak intensity ratio of the tetragonal phase zirconia of 30.2 degrees and the yttria of 48.5 degrees in the ceramic powder is more than 100:1, so that more stable solid solution forms are formed in the ceramic ferrule product, defect points caused by isolated yttria are avoided, high strength is achieved, good ageing resistance is achieved, and the ceramic ferrule product meets the application requirements of the ceramic ferrule.

(3) According to the invention, the ceramic powder with the specific surface area, the specific ratio of D90 to D10 and the 2 theta characteristic peak intensity of tetragonal zirconia at 30.2 degrees and the 2 theta characteristic peak intensity of yttria at 48.5 degrees is compounded, so that the improvement of the ceramic ferrule performance and the improvement of the qualified rate can be realized, no additional equipment is required, a long-time mixing process is not required, and the high realizability and good effect can be realized.

Drawings

Fig. 1 is a schematic diagram of a test for flexural strength of a ferrule.

Detailed Description

The present invention will be described in further detail with reference to specific examples. The starting materials, reagents or apparatus used in the examples and comparative examples were either commercially available from conventional sources or may be obtained by prior art methods unless specifically indicated. Unless otherwise indicated, assays or testing methods are routine in the art.

The performance test and reference standards for each example and comparative example are as follows:

the performance testing step:

1. density testing: the ferrule density was measured using a drainage method.

The empty bottle mass was measured and recorded as m ₁ ；

The mass of the empty bottle after filling with water was measured and recorded as m ₂ ；

The total mass of the empty bottle plus the insert is measured and recorded as m ₃ ；

The total mass of the empty bottle with the insert filled with water was measured and recorded as m ₄ ；

The ferrule density is then calculated according to the following formula:

where ρ is the ferrule density.

2. Flexural strength test:

the ferrule is first placed horizontally on the instrument and then the ram and the ferrule are adjusted to have the ram at the center of the support span and the ferrule. And (3) applying increasing pressure with the speed of 50N/s right above the pressure position, continuously increasing the pressure until the ceramic ferrule breaks, and recording the maximum value of the applied pressure as the breaking strength of the ferrule. The flexural strength data of 10 ferrules are calculated averagely, namely the flexural strength of the ferrule in the invention is represented, and the flexural strength test schematic diagram of the ferrule is shown in figure 1.

3. Ageing resistance test:

polishing the surface of the ferrule sample, checking whether the surface is smooth or has other defects under a microscope, and if so, removing the ferrule with the defects. And (5) flatly laying the core insert in an aging furnace for aging resistance test. The aging oven was preloaded with distilled water 5% of its volume. And after the core insert is placed, the cover is screwed down for heating, the furnace is heated to 121+/-3 ℃, and the pressure in the furnace is set to be 0.12MPa. The aging test time was 72 hours. After the test is finished, taking out the ferrule, observing whether the surface of the ferrule becomes rough, cracks or other defects by using a microscope again, testing the flexural strength of the aged ferrule (the same as the test method (2)), and calculating: retention of heat aging performance of ferrule = flexural strength after heat aging of ferrule/flexural strength before heat aging of ferrule.

4. Coaxiality test:

and cleaning the inner hole of the ceramic ferrule after processing, and ensuring that the inner hole is free of dust, burrs and the like. The ferrule is then placed in the V-groove and rotated. The coaxial detection machine station records fluctuation conditions of the edge of the inner hole along with rotation of the ferrule through the CCD lens, performs image processing, and finally judges whether the ferrule is qualified according to the ferrule industry standard.

Standard reference:

1. core plug density after sintering: the density can indirectly reflect the compactness of the ceramic ferrule, and for the conventional ferrule, the density is more than or equal to 6.0g/cm ³ 。

2. Flexural strength: the flexural strength of the core insert can directly influence the service life of the core insert, and the flexural strength of the manufactured core insert is more than or equal to 1500MPa.

3. Ageing resistance: in the accelerated aging test, after the insert core is placed for 72 hours under the conditions of 120 ℃ and 0.12MPa, the surface is observed to have no defects such as cracks, moire and the like by amplifying by a CCD lens 100 times, if the surface appears, the surface is not qualified, the flexural strength after aging is tested, and the retention rate of the thermal aging performance of the insert core is more than or equal to 98%.

4. Coaxiality: the coaxiality of the insert core reflects the deviation degree of the center of the inner hole and the center of the outer diameter. In the coaxiality detection test, 100 ferrules are subjected to sampling inspection to judge whether the ferrules are qualified or not, and the qualification rate is required to be more than 90%.

Examples 1 to 13 and comparative examples 1 to 7 provide a ceramic ferrule:

the weight content of the ceramic powder in the ceramic ferrule is denoted by A.

The weight content of zirconia in the ceramic powder is represented by B.

The weight content of yttrium oxide in the ceramic powder is represented by C.

The weight content of alumina in the ceramic powder is denoted by D.

The weight content of the organic auxiliary agent in the ceramic ferrule is represented by E, wherein the weight ratio of the binder, the plasticizer, the dispersing agent and the organic macromolecular skeleton component is 3:4:5:8.

The specific surface area of the ceramic powder is denoted by F.

The ratio of D90 to D10 of the ceramic powder is denoted by G.

In the XRD pattern, the ratio of the characteristic peak intensity of the zirconia tetragonal phase at 2θ=30.2° to the characteristic peak intensity of the yttria at 2θ=48.5° in the ceramic powder is represented by H.

The composition of the ferrule is shown in table 1:

TABLE 1 composition of ceramic ferrules.

The binder used in examples and comparative examples was paraffin wax, the plasticizer used was dimethyl phthalate, the dispersant used was stearic acid, and the organic macromolecular skeleton used was polybutylmethacrylate.

The preparation methods of the ceramic ferrules of examples 1 to 13 and comparative examples 1 to 7 are as follows:

s1, mixing process: mixing ceramic powder with organic auxiliary agent (at least one of binder, plasticizer, dispersant and organic macromolecular skeleton) according to the weight content ratio shown in table 1, pouring into a mixing chamber for mixing, wherein the mixing temperature is controlled between 200 ℃, and the mixing time is 3h;

s2, granulating: regulating the screw speed of the granulator to ensure that the material to be granulated obtained in the step S1 has proper fluidity, setting the rotating speed at 70r/min, allowing the mixed material to flow out from an outlet and cutting by a cutter, and finishing granulation;

s3, injection molding process: putting the granulated powder obtained in the step S2 into an injection molding machine, wherein the injection molding process parameters are as follows: the molding temperature is 150 ℃, the molding speed is 20mm/s, the molding peak pressure is 35MPa, the period time is 25s, and the period refers to the total time of different steps (injection molding, pressure maintaining, cooling and storage are one period) of the injection molding machine;

s4, degreasing and sintering process: and (3) putting the molded product obtained in the step (S3) into a kiln, wherein the degreasing temperature is 500 ℃, and the duration is 20h. The sintering temperature is 1200 ℃ and the sintering time is 30 hours.

The results of the performance test of the ceramic ferrule are shown in table 2:

table 2. Results of the performance test of the ceramic ferrules.

As can be seen from Table 1, the compactness and the flexural strength of the ceramic ferrule obtained by the invention meet the index requirements, the probability of cracking and deforming of the ceramic ferrule is greatly reduced, and meanwhile, the ceramic ferrule has excellent thermal ageing resistance, so that the high precision of ceramic ferrule products can be realized, and the qualified rate is improved.

The comparative examples 1-3 and 1-2 can find that the proportion of zirconia ceramic powder has a larger influence on the performance of the final product, the compactness of the material is increased, the flexural strength is also increased, and the coaxiality qualification rate of the final product is also obviously improved along with the increase of the proportion of the powder within a certain range (from 55% -90%). However, when the powder proportion reaches 95%, the maximum allowable powder loading is exceeded, so that the fluidity is lowered, and the plasticization molding cannot be completed.

Comparative examples 1, 4 to 7 and 3 to 4 show that the specific surface area of the zirconia ceramic powder has a large influence on the sintering density and the flexural strength, and defects such as deformation easily occur due to too low, so that the qualification rate of coaxiality is affected. Wherein the specific surface area is 10-20m ² The core insert prepared at the time of/g can meet the application requirement, wherein the specific surface area is 13-17.5m ² The effect per g is the best. When the specific surface area is 8m ² /g and 23m ² And when the core is/g, the former can influence the sintering density, and the latter can lead to poor dispersion due to agglomeration, so that the strength of the prepared core insert can not meet the requirement, and the qualification rate of coaxiality is influenced.

In comparative examples 1, 8-11 and 5-6, it can be found that when the ratio of D90 particle diameter to D10 particle diameter (reflecting the particle diameter distribution) is in a suitable range of 5.0-10.0 on the basis of the same specific surface area, large particle diameter powder and small particle diameter powder are alternately stacked, the small particle diameter powder is just filled in the gaps of the large particle diameter powder, the stacking property and compactness are enhanced, the strength of the ceramic ferrule can reach the maximum value, and the coaxiality qualification rate is relatively higher. Wherein the overall performance is best for ratios between 6 and 8. In comparative examples 5 and 6, when the ratio of D90 particle diameter/D10 particle diameter was 4 and 11, respectively, the density was affected to some extent, resulting in unsatisfactory performance and yield.

Comparative examples 1, 12-13 and 7 show that as the ratio of the 2 theta characteristic peak corresponding to 30.2 deg. of tetragonal zirconia to the 2 theta characteristic peak intensity of yttria at 48.5 deg. is reduced, both the flexural strength of the ferrule and the percent pass of coaxiality of the product are deteriorated, and particularly when the ratio is reduced below 100:1, the performance of the ferrule cannot meet the use requirement, and particularly the small cracks of the manufactured ferrule begin to appear due to the reduction of the thermal aging resistance, which may be related to the solid solution state of yttria formed in zirconia powder.

The above examples are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above examples, and any other changes, modifications, substitutions, combinations, and simplifications that do not depart from the spirit and principle of the present invention should be made in the equivalent manner, and the embodiments are included in the protection scope of the present invention.

Claims

1. The ceramic ferrule is characterized by being prepared from raw materials including ceramic powder; the weight percentage of the ceramic powder in the preparation raw materials is 70% -90%, the ceramic powder comprises zirconia and yttria, and in an XRD spectrum, the ratio of the characteristic peak intensity of tetragonal zirconia at 2θ=30.2 degrees to the characteristic peak intensity of yttria at 2θ=48.5 degrees is greater than 100:1; the specific surface area of the ceramic powder is 10-20m ² /g; the ratio of D90 to D10 of the ceramic powder is 5.0-10.0.

2. The ferrule of claim 1, wherein the ceramic powder has an average particle size of 0.1-0.3 μm.

3. The ceramic ferrule of claim 1, wherein the zirconia is 90-98% by weight of the ceramic powder and the yttria is 1-9% by weight of the ceramic powder.

4. The ferrule of claim 1, wherein the ceramic powder further comprises alumina in an amount of 0.1-1% by weight of the ceramic powder.

5. The ferrule of claim 1, wherein the raw materials for preparing the ferrule further comprise 10-30% by weight of an organic auxiliary agent, the organic auxiliary agent comprises at least one of a binder, a plasticizer, a dispersing agent and an organic macromolecular skeleton, the binder comprises at least one of paraffin wax, polyethylene wax, polypropylene wax and ethylene-vinyl acetate wax, the plasticizer comprises at least one of phthalic acid Dingzhi, dimethyl phthalate, dioctyl terephthalate and dibutyl phthalate, the dispersing agent comprises at least one of stearic acid and oleic acid, and the organic macromolecular skeleton comprises at least one of polymethyl methacrylate, polybutyl methacrylate, polyvinyl shrinkage Ding Quanzhi, polypropylene, polystyrene and polyethylene.

6. The method for manufacturing a ceramic ferrule according to any one of claims 1 to 5, comprising the steps of:

7. The method of preparing a ceramic ferrule of claim 6, wherein the temperature of the mixing is 200-300 ℃;

and/or mixing for 2-5h;

and/or, the temperature of the injection molding is 100-200 ℃;

and/or the injection molding speed is 10-50mm/s;

and/or, the degreasing temperature is 300-800 ℃;

and/or degreasing for 20-50h;

and/or, the sintering temperature is 1200-1500 ℃;

and/or the sintering time is 20-40h.

8. An optical fiber connector comprising the ferrule of any one of claims 1-5.