JPH039223B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to a ceramic fiber blanket that has significantly improved strength in the thickness direction and has a uniform thickness, and a method for manufacturing the same. [Prior Art] As a conventional method for manufacturing ceramic fiber blankets, for example, according to Japanese Patent Publication No. 52-42946, ``a layered ceramic fiber assembly containing an anti-friction agent is needle-punched, and then the anti-friction agent is applied. A method for treating a layered ceramic fiber aggregate is disclosed. [Problems to be Solved by the Invention] The ceramic fiber blanket manufactured by the above-mentioned conventional method has a uniform thickness because it has been subjected to a needling process, but the thickness of the ceramic fiber blanket is uniform in the areas where there are no fibrous loops. It has the disadvantage that the interlayer strength in the direction is weak, causing delamination in some parts. The present invention aims to solve these drawbacks of the prior art, and achieves the object by providing a ceramic fiber blanket and a method for manufacturing the same as set forth in the claims. [Means for Solving the Problems and Their Effects] The ceramic fiber blanket of the present invention and its manufacturing method will be specifically described below with reference to the drawings. FIG. 1 is a longitudinal section of a ceramic fiber blanket of the present invention, and FIG. 2 is a longitudinal section of a conventional ceramic fiber blanket. Conventional ceramic fiber blankets have a structure in which the fibers are entwined only on the back side by needling, as shown in FIG. 2, so the interlaminar strength of the fibers is weak and delamination easily occurs. Therefore, the ceramic fiber blanket 1 of the present invention is made by continuously dotting a large number of fibrous loops 2 formed by needling from the front surface A to the back surface B with overlapping at least their tips. The interlayer strength was significantly improved, and no interlayer peeling occurred at all. In the present invention, if the number of fibrous loops is less than 5 per square centimeter, the blanket will not have sufficient interlaminar strength, and if it is more than 20, the fibers will be significantly broken due to needling and the tensile strength of the blanket will decrease. Undesirable. Next, if the number of continuous fibrous loops 3. from the front surface to the back surface of the blanket is less than one pair per square centimeter, the blanket will not have sufficient interlaminar strength and delamination will occur. FIG. 3 shows a needle board for forming continuous fibrous loops in the thickness direction of the blanket. FIG. 4 shows an enlarged view of the tip of the needle. The ceramic fiber is tied only by the barb 4 at the tip of the needle to form a fibrous loop 2 in the longitudinal direction. Therefore, in conventional ceramic fiber blankets that use one type of needle (with the same tip barb position), the fibrous loops are concentrated only on the back side. Therefore, by intentionally changing the position of the tip barb 4 of the needle, it has become possible to uniformly form fibrous loops in each layer in the thickness direction of the blanket. That is, according to the present invention, uniform fibrous loops can be formed in each layer in the thickness direction by using several types of needles with different lengths or by changing the depth of the groove in which the needles are fixed. [Example] Using a needle board in which five types of needles of different lengths were embedded in a blanket-like laminate of ceramic fibers, the tensile strength of the blanket was subjected to needling treatment and further fired at 600°C. The strength and interlaminar strength were as follows. Note that examples outside the scope of the examples of the present invention are also shown as comparative examples. The interlaminar strength of the blanket was determined by measuring the time required for the blanket to break using a tester as shown in FIG. The blanket 1 is vibrated in the left and right directions of the arrows to cause delamination and the time required until the blanket is cut is measured.

〔Effect of the invention〕

As described above, according to the present invention, it is possible to provide a ceramic fiber blanket with significantly improved interlaminar strength, and it is suitable for heat insulating materials that require interlaminar strength and durability such as locally sintered steel and oil heating furnaces.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal cross-sectional view of a ceramic fiber blanket of the present invention, Fig. 2 is a longitudinal cross-sectional view of a conventional blanket, Fig. 3 is a schematic diagram of a needling device used in the present invention, and Fig. 4 is a needle needle. Fig. 5 is an enlarged view of the tip of , and Fig. 5 is a side view of a testing machine for measuring the needling effect.

Claims (1)

[Scope of Claims] 1. A blanket made of a blanket-like laminate of ceramic fibers, wherein at least 5 to 20 fibrous loops formed by needling exist per square centimeter in the plane direction of the blanket, and the fibrous loops are formed by needling. The presence of one or more pairs of fibrous loops per square centimeter in the plane direction of the blanket, which are continuously scattered from the front surface to the back surface of the blanket, with their tips overlapping each other in each layer of the laminate. A blanket made of ceramic fiber. 2 The number of fibrous loops continuously scattered from the front surface to the back surface of the blanket is 3 per square centimeter in the plane direction of the blanket.
The blanket according to claim 1, characterized in that there are .about.4 pairs. 3 Needling is performed on a blanket-like laminate of ceramic fibers using a needle board in which the position of the tip barb of the needle needle is arranged in stages, so that the fibrous loops are at least 5 to 1 square centimeter per square centimeter in the plane direction of the blanket.
20 and the ends of the fibrous loops are overlapped in each layer of the laminate, and the fibrous loops are continuously scattered from the front surface to the back surface of the blanket at a rate of 1 per square centimeter in the plane direction of the blanket. A method for producing a ceramic fiber blanket characterized by forming two or more pairs of ceramic fibers.