阅读说明：本技术 一种用于高强高模碳化硅纤维的上浆方法 (Sizing method for high-strength high-modulus silicon carbide fiber ) 是由 张新元 杨明杰 张元� 尉寄望 王海涛 于 2020-06-12 设计创作，主要内容包括：本发明公开了一种用于高强高模碳化硅纤维的上浆方法,上浆剂调配：将去离子水、环氧树脂类浆料和亲水性柔软剂以质量比为26～28：4～6：1～3混合搅拌均匀,得到上浆剂；预烘燥：开启烘箱,将温度上升至100℃～130℃；上浆：将碳化硅纤维缠绕在纱筒,经上浆辊进入浆槽,将上浆剂倒入浆槽内对碳化硅纤维进行上浆处理,得到上浆纤维；将上浆纤维经烘箱烘燥后,通过张力控制器、导辊卷绕在绕纱筒上。解决了现有技术中存在的碳化硅纤维在上浆过程中易发毛、断裂,上浆剂不适配的问题。(The invention discloses a sizing method for high-strength high-modulus silicon carbide fibers, which comprises the following steps: deionized water, epoxy resin sizing agent and hydrophilic softening agent are mixed according to the mass ratio of 26-28: 4-6: 1-3, uniformly mixing and stirring to obtain a sizing agent; pre-drying: starting the oven, and raising the temperature to 100-130 ℃; sizing: winding silicon carbide fibers on a bobbin, feeding the silicon carbide fibers into a slurry tank through a sizing roller, and pouring a sizing agent into the slurry tank to perform sizing treatment on the silicon carbide fibers to obtain sizing fibers; and (3) drying the sized fiber by an oven, and winding the fiber on a yarn winding drum through a tension controller and a guide roller. Solves the problems that the silicon carbide fiber is easy to hair and break in the sizing process and the sizing agent is not adaptive in the prior art.)

1. A sizing method for high-strength high-modulus silicon carbide fibers is characterized by comprising the following steps:

step 1, sizing agent blending

Deionized water, epoxy resin sizing agent and hydrophilic softening agent are mixed according to the mass ratio of 26-28: 4-6: 1-3, uniformly mixing and stirring to obtain a sizing agent for later use;

step 2, pre-drying

Starting the oven (5), and raising the temperature to 100-130 ℃;

step 3, sizing

Winding silicon carbide fibers (8) on a bobbin (9), feeding the silicon carbide fibers into a slurry tank (7) through a sizing roller (6), pouring the sizing agent into the slurry tank (7) to perform sizing treatment on the silicon carbide fibers (8) to obtain sizing fibers (3);

and 4, drying the sizing fiber (3) by an oven (5), and winding the sizing fiber on a yarn winding drum (1) through a tension controller (4) and a guide roller (2).

2. The method of claim 1, wherein in step 1, the epoxy resin based slurry is a MU series slurry with a solid content of 50%.

3. The method for sizing a high-strength high-modulus silicon carbide fiber according to claim 1, wherein in step 1, the hydrophilic softener is silicone or glycerol.

4. A sizing method for high-strength high-modulus silicon carbide fiber according to claim 1, wherein the silicon carbide fiber (8) has the following relevant parameters:

the linear density of the fiber is 200 plus or minus 5tex, the tensile strength of the fiber is more than or equal to 2.30Gpa, the elastic modulus is more than or equal to 270Gpa, and the elongation at break is more than or equal to 1.0 percent.

5. A sizing method for high-strength high-modulus silicon carbide fiber according to claim 1, wherein the oven (5) is a hot-air dryer.

6. The sizing method for the high-strength high-modulus silicon carbide fiber according to claim 1, wherein the sizing roller (6) and the guide roller (2) are rolling guide rollers.

Technical Field

The invention belongs to the technical field of preparation of fiber reinforced composite preforms, and particularly relates to a sizing method for high-strength high-modulus silicon carbide fibers.

Background

The silicon carbide fiber is an inorganic fiber obtained by spinning, carbonizing or vapor depositing an organic silicon compound as a raw material, and is also a ceramic fiber with excellent performance. Currently, silicon carbide fibers are sized once when monofilaments are prepared into bundles, but smooth winding of the fibers can only be realized to form a package with a certain specification. Because the silicon carbide fiber has high modulus, thick monofilament diameter and poor bundling property, particularly the fiber has extremely low hooking strength and is easy to break, the fiber bundle is fluffed and broken due to friction in the preparation process of the preform, and the preparation requirements of the subsequent fiber preform cannot be met. Therefore, the secondary sizing of the silicon carbide fiber becomes the difficult point and the key for preparing the silicon carbide fiber preform.

At present, secondary sizing of high-strength high-modulus silicon carbide fibers with extremely low hooking strength by adopting the traditional sizing process and sizing agent still has many problems:

(1) the silicon carbide fiber has the characteristics of high strength and high modulus, thick monofilament diameter, poor bundling property, extremely low fiber hooking strength and easy breakage, and hair and breakage are caused by friction between the silicon carbide fiber bundle and the fiber bundle, between the fiber bundle and a guide roller and between the fiber bundle and a press roller in the sizing process; (2) in the traditional sizing process, thousands of yarns are wound on a warp beam after being warped, and then are sized in batches; this requires that the length of yarn of each package be over kilometers and even more than ten thousand meters, and thousands of yarns enter the size box and the oven through the guide roller simultaneously in the sizing process; however, the package length of the current domestic silicon carbide fiber is only 500-530 m, and the traditional sectional warping or batch warping mode cannot be used for warping and then sizing; in addition, the friction between yarns and guide rollers is large in the batch sizing process, and the yarns and the guide rollers are in sliding friction, so that the silicon carbide fiber bundles are easy to hair and brittle fracture, and huge waste is caused; (3) the traditional sizing agent is prepared by compounding a plurality of chemical additives, and the components of the traditional sizing agent are determined by the yarn performance; for silicon carbide fibers, no chemical auxiliary is currently identified.

Disclosure of Invention

The invention aims to provide a sizing method for high-strength high-modulus silicon carbide fibers, which solves the problems that the silicon carbide fibers are easy to hair and break and sizing agents are not adaptive in the sizing process in the prior art.

The technical scheme adopted by the invention is a sizing method for high-strength high-modulus silicon carbide fibers, which is implemented according to the following steps:

step 1, sizing agent blending

Deionized water, epoxy resin sizing agent and hydrophilic softening agent are mixed according to the mass ratio of 26-28: 4-6: 1-3, uniformly mixing and stirring to obtain a sizing agent for later use;

step 2, pre-drying

Starting the oven, and raising the temperature to 100-130 ℃;

step 3, sizing

Winding silicon carbide fibers on a bobbin, feeding the silicon carbide fibers into a slurry tank through a sizing roller, and pouring a sizing agent into the slurry tank to perform sizing treatment on the silicon carbide fibers to obtain sizing fibers;

and 4, drying the sizing fiber by an oven, and winding the sizing fiber on a yarn winding drum through a tension controller and a guide roller.

The invention is also characterized in that:

in step 1, the epoxy resin slurry is an MU series slurry having a solid content of 50%.

In step 1, the hydrophilic softener is organosilicon or glycerol.

The relevant parameters for silicon carbide fibers are as follows:

the linear density of the fiber is 200 plus or minus 5tex, the tensile strength of the fiber is more than or equal to 2.30Gpa, the elastic modulus is more than or equal to 270Gpa, and the elongation at break is more than or equal to 1.0 percent.

The oven is a hot air blowing type dryer.

The sizing roller and the guide roller are rolling guide rollers.

The invention has the beneficial effects that:

the sizing method for the high-strength high-modulus silicon carbide fiber provided by the invention effectively solves the problems of difficult sizing of the silicon carbide fiber and unmatched sizing agent, only adopts the sizing roller and the guide roller, changes the traditional sliding friction into rolling friction, has soft friction working condition, and greatly reduces the friction between the silicon carbide fiber and between the silicon carbide fiber and the sizing roller; according to the sizing method for the high-strength high-modulus silicon carbide fiber, the unwinding speed of the silicon carbide fiber can be adjusted in the sizing process, the optimal unwinding and winding speeds are determined, the tension uniformity of the silicon carbide fiber during sizing is favorably ensured, frequent brittle fracture caused by uneven tension is avoided, the sizing speed is reduced, and the tension and the sizing efficiency of the silicon carbide fiber during sizing are effectively ensured;

according to the sizing method for the high-strength high-modulus silicon carbide fiber, the silicon carbide fiber bundle is directly unwound from the yarn barrel, so that the problems of silicon carbide fiber hair, yarn splitting and even brittle fracture caused by entanglement, friction and overlapping between the silicon carbide fiber and between the silicon carbide fiber and a sizing roller during batch warping and batch sizing are solved;

the sizing method for the high-strength high-modulus silicon carbide fiber can finish sizing at normal temperature, does not need to boil the sizing before sizing, does not need to preserve the temperature of the sizing liquid during sizing, reduces the complexity of sizing equipment, and also reduces the energy waste in the sizing process; according to the invention, the silicon carbide fiber is not required to be soaked in the sizing agent, and the sizing agent is directly driven by the sizing roller to size the silicon carbide fiber, so that the size hanging amount of the silicon carbide fiber is reduced, and the waste of the sizing agent is reduced.

Drawings

FIG. 1 is a flow chart of a sizing method for high strength and high modulus silicon carbide fibers according to the present invention.

In the figure, 1 is a yarn winding drum, 2 is a guide roller, 3 is sizing fiber, 4 is a tension controller, 5 is an oven, 6 is a sizing roller, 7 is a size groove, 8 is silicon carbide fiber, and 9 is a yarn drum.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings and specific embodiments.

The sizing method for the high-strength high-modulus silicon carbide fiber disclosed by the invention is implemented according to the following steps as shown in figure 1:

step 1, sizing agent blending

Deionized water, epoxy resin sizing agent and hydrophilic softening agent are mixed according to the mass ratio of 26-28: 4-6: 1-3, uniformly mixing and stirring to obtain a sizing agent for later use;

the epoxy resin sizing agent is MU series sizing agent with solid content of 50%; the hydrophilic softening agent is organic silicon or glycerin;

the epoxy resin sizing agent has good film forming property and adhesiveness; can be completely volatilized in a high-temperature environment, and the performance of the sizing fiber 3 is kept; the silicon carbide fibers 8 can be bonded together, the bundling property of the silicon carbide fibers 8 is improved, meanwhile, a layer of protective film can be formed on the surfaces of the silicon carbide fibers 8 to completely adhere to the broken filaments on the surfaces of the fibers, more broken filaments generated by contact friction of the silicon carbide fibers 8 in the subsequent weaving process are avoided, and the weaving performance of the silicon carbide fibers 8 is improved;

step 2, pre-drying

Starting the oven 5, raising the temperature to 100-130 ℃, and keeping the temperature constant; wherein, the drying oven 5 is a hot blowing type drying machine;

step 3, sizing

Winding silicon carbide fibers 8 on a bobbin 9, feeding the silicon carbide fibers into a slurry tank 7 through a sizing roller 6, pouring a sizing agent into the slurry tank 7 to perform sizing treatment on a single silicon carbide fiber 8, reducing damage caused by friction among the silicon carbide fibers 8, and obtaining sizing fibers 3;

when the silicon carbide fiber 8 is wound on the sizing roller 6, the force needs to be slowly and uniformly applied, so that the tensile property of the silicon carbide fiber 8 is prevented from being damaged due to uneven stress, and even the fiber is prevented from being broken; adding the prepared sizing agent into the size box 7, wherein the volume of the size box 7 needs to be 2/3, and when the sizing agent in the size box 7 is less than 1/3, the sizing agent needs to be continuously added to 2/3 of the volume of the size box 7;

the relevant parameters of the silicon carbide fiber 8 are as follows:

the linear density of the fiber is 200 plus or minus 5tex, the tensile strength of the fiber is more than or equal to 2.30Gpa, the elastic modulus is more than or equal to 270Gpa, and the elongation at break is more than or equal to 1.0 percent;

the relevant parameters of the sizing fibres 3 are as follows:

the linear density of the fiber is 200.4tex, the tensile strength of the fiber is 2.91Gpa, the elastic modulus is 303Gpa, and the elongation at break is 1.22%;

step 4, drying the sizing fiber 3 by an oven 5, and winding the sizing fiber on a yarn winding drum 1 through a tension controller 4 and a guide roller 2;

wherein, the sizing roller 6 and the guide roller 2 are rolling guide rollers, and the sizing roller 6 and the guide roller 2 need to be wiped smoothly before use, so that the sizing roller 6 and the guide roller 2 are prevented from damaging the silicon carbide fiber 8 due to broken filaments, residual pulp and the like.