JPH02196104A - Fiber reinforced ceramic turbine blade - Google Patents

Abstract

PURPOSE:To make manufacturing and assembling easy while to improve strength in the required direction by forming a through such process turbine blade as laminating ceramic films having a hollow part in the center part and reinforced with such as long fibers arranged in every direction, across a range from the innermost layer part to the outermost layer part. CONSTITUTION:A bucket 1 is formed of a blade part 2 for receiving high temperature, high pressure gas flow, a platform part 3 connected to the blade part 2, and a dovetail part 4 held in a disc to be a rotation axis. Together with forming respective parts 3, 4 in an integral construction, a recessed part 3a in to which the blade part 2 is fitted is formed in the platform part 3. In this case, the blade part 2 is formed of a laminated body 6 in the center part of which a hollow part 5 is present. The laminated body 6 is formed in a stream- line shape in its section while is formed of ceramic films 7 composed of long fibers or short fibers laminated in parallel across a range from the innermost layer part to the outermost layer part. And respective fibers are arranged in different directions in respective layers.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application J] The present invention relates to a fiber-reinforced ceramic turbine, and more particularly, to a ceramic turbine having an airfoil reinforced with ceramic fibers, which is manufactured by increasing the strength and toughness of the airfoil. The present invention relates to fiber-reinforced ceramic turbines that can improve performance.

[Prior Art J] Turbine blades of gas turbines used for power generation and transportation are required to handle high temperatures and high speeds. For this reason,
This type of turbine blade requires strength and toughness;
In recent years, ceramic wing parts reinforced with ceramic fibers have been attracting attention.

In general, fiber-reinforced ceramic wing parts are roughly divided into those made of long fibers and those made of short fibers. In the case of long fibers, the entire wing part is reinforced with one-dimensional, two-dimensional, or three-dimensional continuous fibers as a -tJk structure. was being done. Furthermore, in the case of short fibers, the short fibers were almost randomly oriented dispersed throughout the wing.

[Challenges to be solved by the invention] By the way, it is difficult to use long fibers for parts of the wing parts that have complex shapes, as in the former case, and especially for parts of the wing parts that have shapes such as fastening parts. There was a problem with poor manufacturability due to the complicated shape. Additionally, it has been difficult to strengthen the long fiber bonds of an integrated structure, taking into account the direction in which strength is required.

On the other hand, the latter type of wing section using short fibers has problems in that it is not easy to manufacture parts with complex shapes, or it is not possible to increase the strength in the required directions.

The present invention has been devised to effectively solve the above problems.

SUMMARY OF THE INVENTION An object of the present invention is to provide a fiber-reinforced ceramic turbine blade that can improve the manufacturability and assemblability of the blade part and increase the strength in required directions.

[Means and effects for solving the problem] The present invention provides a ceramic membrane having a cavity in the center and reinforced with long fibers or short fibers oriented in one direction or two dimensions, from the innermost layer to the outermost layer. The wing section, which requires particularly strength and toughness, has a laminated structure of fiber-reinforced ceramic membranes, and by changing the direction of fiber orientation for each layer of the ceramic membrane, the direction of the fibers can be adjusted. This allows for multidimensional orientation.

[Example] An embodiment of the present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 shows a rotor blade of a turbine blade that is rotationally driven by a high-temperature, high-pressure gas flow.

As shown in the figure, the rotor blade 1 consists of a blade section 2 which receives a flow of high-temperature, high-pressure gas, a platform section 3 connected to the blade section 2, and a dovetail section 4 held by a disk serving as a rotating shaft. Mainly composed of

The platform portion 3 and the dovetail portion 4 are integrally formed, and the platform portion 3 is formed with a recess 3 a for holding the base end portion of the wing portion 2 .

In particular, the wing section 2 is constituted by a laminate 6 having a cavity 5 in its center (axial center). As shown in FIGS. 2 and 3, this laminate 6 has a streamlined cross-section and is made of ceramic membranes made of long fibers or short fibers laminated in parallel from the innermost layer to the outermost layer. In the illustrated example, ceramic IN! 7 are laminated into a three-layer structure consisting of an innermost layer, an intermediate layer, and an outermost layer.

Further, the fibers of these shellac membranes 7 are oriented in different directions for each layer.

Specifically, the ceramic membrane 7 includes ceramic long fibers oriented in one direction or two-dimensionally oriented in a fabric-like manner, or ceramic fibers oriented in one direction or two-dimensionally oriented even if the in-plane orientation is randomly oriented. Constructed of ceramics reinforced with short ceramic fibers.

For example, the wings 2 are formed by stacking silicon carbide ceramic membranes 7 reinforced with unidirectionally oriented silicon carbide whiskers.

Moreover, the platform part 3 and the dovetail part 4 are formed of isotropic ceramics. In other words, even if the ceramic is not reinforced with fibers or reinforced with short fibers, the orientation is random.

For example, a platform portion 3 and a dovetail portion 4 made of silicon nitride ceramics reinforced with randomly oriented silicon carbide whiskers are formed, and the blade portion 2 is joined to these to form a turbine rotor blade l. The rotor blade 1 is fitted and attached to a metal disk forming a rotating shaft.

Therefore, by orienting the fibers of each ceramic M7 of the laminate 6 constituting the wing section 2 in different directions for each layer, it becomes possible to combine and orient the fiber directions multidimensionally. For this reason, it is possible to handle parts with complex shapes, improve manufacturability, and provide strength and strength in the required direction.
Toughness can be controlled and increased.

In addition, a cavity 5 formed in the center part (axis center part) of the wing part 2
can be used as a cooling space. That is, a passage 4a communicating with the cavity 5 of the blade part 2 is formed in the dovetail part 4, and by supplying cooling air to the cavity 5 of the blade part 2 through this passage 4a, the entire rotor blade is cooled. Can be cooled.

This is particularly effective when the turbine inlet temperature is extremely high. At high speed and high rotation, the turbine inlet temperature is 1500℃.
℃ and a circumferential speed of 700 m/s.

Moreover, in this case, since the cavity 5 is formed in the wing section 2,
Since the heat capacity is small, the unsteady thermal stress at the time of starting and stopping the turbine is reduced, and the weight is also reduced, so the stress caused by centrifugal force on the rotor blades is reduced.

Further, a ceramic member or a metal member can be inserted into and passed through the cavity 5 of the wing portion 2. Therefore, the wing portion 2 can be easily fastened, and the ease of assembly is improved.

For example, as shown in FIGS. 4 and 5, the central portion of the platform portion 3 extends into the hollow portion 5 of the wing portion 2, and the extending portion 8 is inserted and held within the hollow portion 8. In this case, the one-ratform portion 3 and dovetail portion 4 of the extending portion 8 are made of isotropic ceramics, as in the above embodiment.

Therefore, by configuring the inside of the blade section 2, the platform section, and the dovetail section 4 with GaN ceramics reinforced with randomly oriented GaN carbide whiskers, the rotor blade 1 can be constructed using a ceramic reinforced with randomly oriented GaN carbide whiskers. W shock resistance when compared to membrane turbine blades,
Excellent properties were obtained in both erosion and thermal shock resistance.

On the other hand, FIG. 6 shows a stator blade of a turbine blade, and the stator blade 10 has a cavity 11 in the center (axial center).
A wing portion 12 is formed. This wing section 12 has a laminate 13 with a three-layer structure, and this laminate 13 has a silicon carbide ceramic film 14 reinforced with three types of oriented fibers laminated from the innermost layer to the outermost layer. It is constituted by

In this example, the outermost layer is reinforced with unidirectionally oriented silicon carbide whiskers, the middle layer is reinforced with two-dimensionally woven silicon carbide long fibers, and the innermost layer is reinforced with two-dimensionally randomly oriented silicon carbide short fibers.

Therefore, as in the above embodiment, since the ceramic membrane 14 is oriented in different directions for each layer, the fiber orientation is multidimensionally oriented, and the strength of the wing portion 12 can be increased.

Further, a rod 15 is inserted and fitted into the cavity 11 of the wing section 12, and a sheroud 16 and a fastening section 17 are integrally formed on this rod 15. The rod 15, shell 16, and fastening portion 17 are made of isotropic ceramics, that is, ordinary dihydrogen carbide ceramics.

The stator blade 10 constructed in this manner exhibited superior characteristics in impact resistance against flying particles and thermal shock resistance when compared with a stator blade whose entire blade was made of ordinary silicon carbide ceramics.

[Effects of the Invention] In summary, the present invention exhibits the following excellent effects.

(1) The wing has a cavity in the center and is made of laminated ceramic membranes reinforced with long or short fibers, so it can accommodate complex shaped parts of the wing.
Excellent manufacturability.

(2) Since the optimal fiber orientation direction of the ceramic membrane is selected for each layer, the fiber orientation can be multidimensionally oriented, and the strength and toughness of the wing section can be controlled and increased in the required directions.

(3) Complex-shaped parts other than the blades are made of isodirectional ceramics that are highly manufacturable, and the 1a fiber oriented blades are integrated, making it easy to manufacture and design the turbine blade.

[Brief explanation of the drawing]

Figure 1 is a sectional view of the rotor blade, Figure 2 is a view taken along the line ■-■ in Figure 1, Figure 3 is a perspective view of the blade section of the rotor blade, and Figure 4 is a view of other parts of the rotor blade. A sectional view showing the embodiment, FIG. 5 is taken along V-v in FIG. 4.
The line arrow view and FIG. 6 are cross-sectional views showing the stationary blades. In the figure, 2 and 12 are wing portions, and 7 and 14 are ceramic membranes. Patent Applicant: Ishikawajima-Harima Heavy Industries Co., Ltd. Representative Patent Attorney Nobuo Kinutani Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6

Claims (1)

[Claims] 1. It is characterized by having a cavity in the center and laminated from the innermost layer to the outermost layer of ceramic membranes reinforced with long fibers or short fibers oriented in one direction or two dimensions. Fiber-reinforced ceramic turbine blade.