阅读说明：本技术 一种整体叶盘稳定约束层的定轴旋转激光喷丸方法 (Fixed-axis rotating laser shot blasting method for blisk stable constraint layers ) 是由 张峥 吴瑞煜 张永康 于 2019-10-18 设计创作，主要内容包括：本发明公开了一种整体叶盘稳定约束层的定轴旋转激光喷丸方法,包括稳定约束层的辅助支撑和轴向固定夹具,稳定约束层的辅助支撑是通过叶片外形进行等量外扩偏置获得,具有良好的贴合性,通过扩展叶片边界尺寸可获得厚度稳定的约束层,轴向定位夹具配备分度盘,可依据叶盘上叶片数量进行等角度旋转,通过编制单个叶片程序配合夹具的定角度旋转,可大幅降低程序复杂度并提升叶片加工的可靠性。(The invention discloses a fixed-axis rotation laser shot blasting method for blisk stable constraint layers, which comprises auxiliary supports and an axial fixing clamp for the stable constraint layers, wherein the auxiliary supports for the stable constraint layers are obtained by performing equal-amount outward expansion and bias on the shapes of blades, the stable constraint layers have good fitting performance, the constraint layers with stable thickness can be obtained by expanding the boundary size of the blades, the axial positioning clamp is provided with an index plate and can rotate at equal angles according to the number of the blades on the blisk, and the program complexity can be greatly reduced and the processing reliability of the blades can be improved by programming a single blade and matching the fixed-angle rotation of the clamp.)

1, kinds of blisk stable constraint layer fixed axis rotation laser shot blasting method, characterized in that, including the following steps:

step S1: mounting the whole blade disc on an axial positioning fixture, and clamping and fixing;

step S2: obtaining the shape and size of each blade on the blade: the blade shape of each blade on the blade disc can be obtained by design drawings or reverse engineering, and then an auxiliary support for assisting the blade machining is designed according to the obtained dimension data;

step S3: installing an auxiliary support on the blade, and connecting and fixing the blade and the auxiliary support by using a black adhesive tape;

step S4, arranging constraint layers with stable thickness at the processing edges of the blades;

step S5: and the shooting end of the laser shot blasting processes the blade edge.

2. The fixed-axis rotary laser peening method of the blisk stable constraint layer according to claim 1, wherein the axial positioning fixture comprises a bottom plate, a base, an indexing disc, a large conical positioning block and a small conical positioning block, the bottom plate is mounted at the tail end of a robot arm through bolts, the indexing disc is fixedly mounted on the bottom plate through the base, the output end of the indexing disc is fixedly connected with the large conical positioning block, the blisk is arranged on the large conical positioning block, the side of the blisk is fixedly connected with the large conical positioning block, and the other side of the blisk is fixedly connected with the small conical positioning block.

3. The method of claim 2 wherein said axial positioning fixture further comprises a pointer for marking currently processed blades, said pointer being mounted on said base plate and indexed through an angle of units after processing blades.

4. The method of claim 1, wherein said step S2 further comprises: and (3) establishing a blade appearance model in three-dimensional modeling software, and obtaining appearance and size data of the whole auxiliary support by using an equivalent outward expansion biasing function.

5. The method of claim 4, wherein said step S2 further comprises: and subtracting the appearance of the blade through Boolean operation to obtain the auxiliary support with increment in three directions except the root of the blade.

6. The method of claim 1, wherein the distance between the inner edge of the auxiliary support and the blade is set to be 1 to 4 mm.

7. The method of claim 1, wherein said thickness stabilized constraining layer in step S4 is formed by approximately elliptical regions of stabilized thickness radiating outward from the center of the water jet.

8. The method of claim 1, wherein said step S5 further comprises: when a single blade is subjected to laser shot blasting, the auxiliary support is adopted to ensure the processing quality of the air inlet/outlet edge of the blade disc, and after the optimal processing parameters are determined through multiple process tests, the program parameters can be determined and the parameters are fixed.

9. The method for fixed-axis rotation laser peening of blisk stable constraining layer according to claim 1, wherein the step S5 further comprises machining blades each time, and after the machining of a single blade is completed, the axial positioning fixture drives the blisk to rotate integrally

Technical Field

The invention relates to the technical field of aviation manufacturing, in particular to a fixed-axis rotating laser shot blasting method for blisk stable constraint layers.

Background

The novel structural member that blisk (Integral Bladed rotor) designed in order to satisfy high performance aeroengine, it forms bodies with engine rotor blade and rim plate, has saved tenon, tongue-and-groove and locking device etc. in traditional connection, reduces structure weight and part quantity, avoids tenon air current loss, improves aerodynamic efficiency, makes the engine structure greatly simplify, has now obtained general application on military and civilian aeroengine of each country.

During the use of the engine, the rotor blade is often damaged by foreign objects or cracks appear due to vibration, so the fatigue resistance and high reliability of the structure are the difficulties in manufacturing the blisk. Laser peening is a surface strengthening technology that currently solves the problems of foreign object damage resistance and high cycle fatigue resistance. The material is strengthened by mainly utilizing directional high-pressure high-speed shock waves generated by the interaction of a sacrificial layer (black adhesive tape/aluminum foil) and a constraint layer (water flow) with high-energy pulse laser, the microstructure transformation is guided, and the residual compressive stress is introduced, so that the damage tolerance and the fatigue life of the material are improved.

However, the integral leaf disk has two technical difficulties in laser shot blasting, namely is the stability and reliability of boundary processing, the air inlet/outlet edge of the leaf is a key bearing area of the structure, and due to the aerodynamic design requirement, the thickness of the air inlet/outlet edge is thin and the rigidity is weak, water flow is influenced by gravity and geometric mutation (free from attachment and support) in the boundary area, a constraint layer with stable thickness is difficult to form, so that the laser shot blasting condition is unstable and reliable, and the processing quality is uneven.

Secondly, the complexity of a machining procedure is high, 24-36 blades are generally uniformly distributed on the circumference of the blisk, the angle of each blade is different, the air inlet/outlet edges of the blades need to be treated, at least 24-36 stations are involved, the complexity and controllability of the machining procedure are poor, the process reliability is difficult to guarantee, and the requirement of high reliability of an aviation key structural component is difficult to meet.

Therefore, there is a need in the art for improvements and improvements.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provides fixed-axis rotating laser shot blasting methods for a blisk stable constraint layer.

The purpose of the invention is realized by the following technical scheme:

kinds of blisk stable constrained layer fixed-axis rotation laser shot blasting method, which mainly comprises the following concrete steps:

step S1: mounting the whole blade disc on an axial positioning fixture, and clamping and fixing;

step S2: obtaining the shape and size of each blade on the blade: the blade shape of each blade on the blade disc can be obtained by design drawings or reverse engineering, and then an auxiliary support for assisting the blade machining is designed according to the obtained dimension data;

as a preferable embodiment of the present invention, the step S2 further includes: and (3) establishing a blade appearance model in three-dimensional modeling software, and obtaining appearance and size data of the whole auxiliary support by using an equivalent outward expansion biasing function.

As a preferable embodiment of the present invention, the step S2 further includes: and subtracting the appearance of the blade through Boolean operation to obtain the auxiliary support with increment in three directions except the root of the blade.

As a preferable aspect of the present invention, a distance between the inner edge of the auxiliary support and the blade is set to be 1 to 4 mm. Preferably, the clearance between the auxiliary support and the blades is set to be 1-2 mm, and is determined according to the number of the blades and the space allowance.

Step S3: installing an auxiliary support on the blade, and connecting and fixing the blade and the auxiliary support by using a black adhesive tape;

step S4, arranging constraint layers with stable thickness at the processing edges of the blades;

as a preferable aspect of the present invention, the thickness-stabilized constraining layer in step S4 is formed by an approximately elliptical stable thickness region radiating outward from the center of the water jet.

Step S5: and the shooting end of the laser shot blasting processes the blade edge.

As a preferable embodiment of the present invention, the step S5 further includes: when a single blade is subjected to laser shot blasting, the auxiliary support is adopted to ensure the processing quality of the air inlet/outlet edge of the blade disc, and after the optimal processing parameters are determined through multiple process tests, the program parameters can be determined and the parameters are fixed.

As a preferable scheme of the invention, the step S5 further comprises the steps of only processing blades each time, and after the processing of a single blade is finished, driving the blade disc to integrally rotate by the axial positioning clamp

And the angle is changed, the pointer is shifted to mark the blade being processed, and the single blade processing program is operated again.

More importantly, the blades of the blisk are processed under the same conditions and parameters, the quality stability is ensured, and an operator is not easy to make mistakes during the processing process, so that the blisk is the simplest and most effective method for engineering production.

The axial positioning clamp comprises a bottom plate, a base, an indexing disc, a large conical positioning block and a small conical positioning block, wherein the bottom plate is installed at the tail end of a robot arm through bolts, the indexing disc is fixedly installed on the bottom plate through the base, the output end of the indexing disc is fixedly connected with the large conical positioning block, a vane disc is arranged on the large conical positioning block, the side of the vane disc is fixedly connected with the large conical positioning block, and the side of the vane disc is fixedly connected with the small conical positioning block.

The pointer is arranged on the bottom plate, and is shifted to an angle of units after blades are machined.

Compared with the prior art, the invention also has the following advantages:

(1) the fixed-axis rotation laser shot blasting method for the blisk stable constraint layer provided by the invention has the advantages that the program complexity can be greatly reduced and the processing reliability of the blade can be improved by programming a single blade program and matching the fixed-angle rotation of the clamp with the repeated program and the rotating blisk angle during processing.

(2) The fixed-axis rotation laser shot blasting method for the blisk stable constraint layer provided by the invention obtains the shape and size data of the auxiliary support by carrying out equal external offset on the overall size of the blade, so that the auxiliary support has good fitting property when being installed on the blade.

(3) The fixed-axis rotation laser shot blasting method for the blisk stable constraint layer provided by the invention adopts customized auxiliary support, uniformly expands the processing area of the air inlet/outlet edge of the blade, and provides physical support for forming stable laminar flow for the water flow of the constraint layer, thereby ensuring the stability and uniformity of boundary conditions during processing.

Drawings

FIG. 1 is a schematic view of the combination of the auxiliary support, the blade, the black tape and the constraint layer provided by the present invention.

Fig. 2 is a schematic view of a clamping structure between the axial positioning fixture and the blisk.

Fig. 3 is a schematic diagram of the boundary of the stable constrained layer obtained after the auxiliary support is adopted.

Fig. 4 is a schematic diagram of the boundary of the unstable constraint layer obtained without using the auxiliary support provided by the present invention.

The reference numerals in the above figures illustrate:

1-auxiliary support, 2-blade, 3-black adhesive tape, 4-constraint layer, 5-water spray pipe, 6-stable constraint layer boundary (obtained after using auxiliary support), 7-unstable boundary (boundary when not using auxiliary support), 8-bottom plate, 9-pointer, 10-base fixing hole, 11-base and dividing disc, 12-large conical positioning block, 13-blade disc and 14-small conical positioning block.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention clearer and clearer, the present invention is further illustrated in below by referring to the accompanying drawings and examples.