JPS63259040A - Manufacture of cylindrical fiber compact for reinforcement - Google Patents

Abstract

PURPOSE:To obtain the titled fiber compact which is improved in strength and in which fiber exfoliation is inhibited, by applying sucking action to the inside of a cylindrical mold to allow fiber reinforcement and inorganic binder to adhere to the outside peripheral surface of the mold, by applying and impregnating inorganic binder to and into the inside peripheral surface along the compact material after heating and burning, and then by applying heating and drying. CONSTITUTION:A mold 2 is immersed, e.g., in an aqueous solution 1 of compacting material containing alumina fiber and binder such as silica sol, and a medium is sucked 3 via the mold 2. By this procedure, a compact material 4 in which the alumina fiber is allowed to adhere together with the binder to the outside peripheral surface of the mold 2 is prepared. Subsequently, the material 4 is dried and burned together with the mold 2 in a drying furnace 5 and then subjected to mold release. The material 4 released from the mold is placed on a turntable 6 and, while turning the material 4, the above-mentioned binder is sprayed 7 on the internal, surface and a dry hot-air jet pipe 9 is inserted into the inside peripheral side of the material 4, and the internal surface 4a of the material 4 is dried by heating to undergo burning. By this method, a cylindrical fiber compact for reinforcement in which binder distribution in the inside peripheral layer is finely regulated and binder distribution is uniformized in both inside and outside peripheral layers can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a method for manufacturing a reinforcing cylindrical fiber molded body used in manufacturing a fiber composite member.

<Prior Art> Fiber-reinforced composite materials manufactured by mixing alumina fibers or the like into the structure of a base metal are known.

As a method for manufacturing reinforcing fiber molded bodies used in this type of composite material, as disclosed in JP-A No. 60-243240, for example, a breathable cylindrical mold or the like is used to mold reinforcing fibers and inorganic It is known that the molding material is immersed in an aqueous solution containing a binder and a suction action is applied to the inside of the mold, thereby causing the molding material to adhere to the outer peripheral surface of the mold.

<Problems to be Solved by the Invention> The material of the fiber molded body formed in this way contains a large amount of water and has poor shape retention if left as is, so it is heated and dried together with the mold. . Therefore, the drying of the material of the fiber molded body progresses from the outer peripheral surface, and the binder particles float to the outer peripheral layer of the molded body material due to the flotation phenomenon, and the binder portion 15 in the inner peripheral layer tends to become sparse.

Therefore, there was a problem in that the fiber bonding strength on the inner peripheral side was insufficient, resulting in fiber peeling and cracking.

In view of the problems of the prior art, the main purpose of the present invention is to homogenize the binder distribution inside the material of the fiber molded body,
An object of the present invention is to provide a method for manufacturing a reinforcing cylindrical fiber molded article that can improve fiber bond strength.

<Means for Solving the Problems> According to the present invention, an air permeable cylindrical mold with both ends sealed is immersed in an aqueous solution of a molding material containing reinforcing fibers and an inorganic binder. and a step of adhering the molding material to the outer peripheral surface of the mold by applying suction into the mold, and drying and baking the molded body material formed through this step by heating from its outer surface. A method for producing a reinforcing cylindrical fiber molded article, the method comprising:
The method comprises a step of impregnating the inorganic binder only on the inner peripheral surface of the molded material released from the mold, and a step of heating and drying the inner peripheral surface of the molded material after the step. This is achieved by providing a method for manufacturing a reinforced cylindrical fiber molded article characterized by the following.

<Function> In this way, by applying the binder to the inner peripheral surface of the molded material that has been preformed and has undergone the drying process from the outer peripheral surface, the binder is supplemented to the inner peripheral layer, which tends to be sparse, and the inner peripheral layer is By heating and drying from the surface side, binder particles float to the inner peripheral layer, thereby strengthening the inner peripheral surface.

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

First, as shown in FIG. 1, a mold 2 formed by sealing the openings at both ends of a cylindrical part made of shell sand is immersed in an aqueous solution 1 of a molding material containing alumina fibers and a binder such as silica sol. A suction pump 3 sucks the medium through the mold 2 . As a result, the alumina fibers are attached to the outer peripheral surface of the mold 2 together with the binder, and a molded body material 4 is formed.

The molded body material 4 attached to the outer peripheral surface of the mold 2 is shaped using a rubber press or the like, and then heated together with the mold 2 in a drying oven 5 as shown in FIG. The heat source 1 faces the outer peripheral surface of the molded body material 4, and the molded body material 4 is
Drying progresses more than the outer layer, which is in direct contact with the outside air. Therefore, the binder particles move to the outer peripheral layer due to the flotation phenomenon, and therefore the binder distribution in the inner peripheral layer in contact with the mold 2 becomes sparse.

The molded body material 4, which has been dried and baked into a difficult shape in this manner, is placed on the turntable 6, and a binder is sprayed onto the inner surface of the molded body material 4 while rotating the molded body material 4. At this time, the binder is applied evenly and uniformly to the inner surface 4a of the molded body material 4 while moving the spray nozzle 7 in the vertical direction, and the binder is impregnated into the fiber layer (FIG. 3).

Next, as shown in FIG. 4, an electric heater 8 is inserted into the inner circumferential side of the molded body material 4, or a dry hot air jet tube 9 is inserted as shown in FIG. inside i! i'i
4a is heated and dried and fired. As a result, the binder content of the inner circumferential layer is closely adjusted, and the binder distribution in both the inner and outer circumferential layers is made uniform.

In this way, the radial crushing load is increased by approximately 60% compared to the conventional molded material in which only the outer peripheral layer is dried,
The amount of surface peeling could be reduced to 115 or less.

<Effects of the Invention> According to the present invention, by impregnating the inner peripheral layer, which has become sparse due to the binder flotation phenomenon, with the binder again, the bonding strength of the fibers can be made uniform in both the inner and outer peripheral layers. , improve the strength of reinforcing cylindrical fiber molded bodies,
It is highly effective in suppressing fiber peeling.

[Brief explanation of the drawing]

FIGS. 1 to 4 are process diagrams showing an embodiment of the method for producing a reinforcing cylindrical fiber molded body according to the present invention. FIG. 5 is an explanatory diagram showing another example of the drying process. 1... Aqueous solution 2... Molding mold 3... Suction pump 4... Molded body material 4a... Inner surface
5...Drying oven 6...Turntable 7...
Spray nozzle 8...Electric heater 9...Dry hot air jet Applicant: Honda Motor Co., Ltd. Representative Patent attorney: Yo Oshima - No. 2
Figure 4 Figure 5

Claims (1)

[Claims] A cylindrical mold with air permeability sealed at both ends is immersed in an aqueous solution of a molding material containing reinforcing fibers and an inorganic binder,
A step of adhering the molding material to the outer circumferential surface of the mold by applying suction into the mold, and a step of drying and baking the molded body material formed through this step by heating from its outer surface. A method for producing a reinforcing cylindrical fiber molded body, comprising: applying and impregnating the inorganic binder only on the inner circumferential surface of the molded body material released from the mold; and after the step, the molding. 1. A method for producing a reinforcing cylindrical fiber molded body, comprising the step of heating and drying the inner circumferential surface of a body material.