A seed crystal orientation testing fixture for single-crystal blades and its application method

Abstract

A seed crystal orientation testing fixture for single-crystal blades and its usage method are disclosed. The fixture includes a base, a clamping platform, a pressure plate, and clamping screws. The clamping platform is placed on the base; the seed crystal is placed inside the clamping platform; the pressure plate is located above the seed crystal; and the clamping screws are vertically installed on the clamping platform above the pressure plate. The method involves: loading the seed crystal into the fixture to form a seed crystal clamping assembly; electrolytically polishing the exposed section of the seed crystal on the clamping assembly; positioning the seed crystal clamping assembly in a crystal orientation analyzer using the base; analyzing and testing the primary dendrite orientation of the seed crystal end face; adjusting the placement direction of the seed crystal clamping assembly and repositioning it; and analyzing and testing the secondary dendrite orientation of the seed crystal side face. This invention can meet the needs of batch electrolytic polishing of seed crystals and the requirements of batch analysis and testing of seed crystal orientation, significantly improving the seed crystal preparation efficiency and thus better meeting the needs of actual production schedules.

Description

Technical Field

[0001] This invention belongs to the field of aero-engine component manufacturing technology, and in particular relates to a seed crystal orientation testing fixture for single-crystal blades and its usage method. Background Technology

[0002] Nickel-based single-crystal superalloys exhibit significant anisotropy in their mechanical properties. By controlling the primary and secondary dendrite orientations of single-crystal blades, the service life of the blades can be significantly improved.

[0003] The seed crystal method can achieve precise control of the orientation of epitaxial growth grains by accurately positioning the pre-placed seed crystal, thereby achieving effective control of the three-dimensional orientation of single crystals. However, this process has high requirements for the initial orientation of the seed crystal.

[0004] Direct casting of seed crystals or electrical discharge machining of single crystal test rods or pieces are common methods for preparing seed crystal samples. To ensure the accuracy of the original orientation of the seed crystal, a crystal orientation analyzer is needed to confirm the primary and secondary dendrite orientation of the seed crystal sample in order to meet the control requirements of the three-dimensional orientation of single crystal blades.

[0005] However, seed crystal samples prepared by direct casting or electrical discharge machining will have an oxide layer of a certain thickness on their surface, which will directly affect the analysis and testing of crystal orientation.

[0006] Therefore, to meet the analytical testing requirements for seed crystal orientation, mechanical polishing is typically used to remove the oxide layer from the surface of the seed crystal sample. However, mechanical polishing is inefficient and cannot meet the requirements for batch analytical testing of seed crystal orientation, thus further reducing the efficiency of seed crystal preparation and making it difficult to keep up with actual production schedules. Summary of the Invention

[0007] To address the problems existing in the prior art, this invention provides a seed crystal orientation testing fixture for single crystal blades and its usage method, which can meet the needs of batch electrolytic polishing of seed crystals, and at the same time meet the requirements of batch analysis and testing of seed crystal orientation, and can significantly improve the preparation efficiency of seed crystals, thereby better meeting the actual production schedule requirements.

[0008] To achieve the above objectives, the present invention adopts the following technical solution: a seed crystal orientation testing fixture for single crystal blades, comprising a base, a clamping platform, a pressure plate, and a clamping screw; the clamping platform is placed on the base; the seed crystal is placed inside the clamping platform; the pressure plate is located above the seed crystal; the clamping screw is vertically installed on the clamping platform above the pressure plate.

[0009] The base adopts an L-shaped structure, and the two support arms of the base are referred to as the first support arm and the second support arm respectively; the end face of the first support arm is designated as the first reference surface, the outer surface of the first support arm is designated as the second reference surface, the inner surface of the first support arm is designated as the third reference surface, and the inner surface of the second support arm is designated as the fourth reference surface.

[0010] The clamping platform adopts an inverted T-shaped groove structure. Several seed crystal slots are evenly distributed on the bottom surface of the inverted T-shaped groove of the clamping platform, and one end of the seed crystal is located in the seed crystal slot.

[0011] The lower surface of the clamping platform is designated as the fifth reference surface, and the back surface of the clamping platform is designated as the sixth reference surface.

[0012] The pressure plate is located in the inverted T-shaped groove of the clamping stage and directly above the seed crystal slot. A rubber pad is fixedly attached to the lower surface of the pressure plate.

[0013] The number of clamping screws is two. Each of the two clamping arms at the top of the inverted T-shaped groove of the clamping platform is equipped with a clamping screw, and the screw end of the clamping screw is directly opposite the upper surface of the pressure plate.

[0014] A positioning block is provided on the back of the clamping platform, and the positioning block is fixedly connected to the clamping platform by fastening screws.

[0015] The method of using the seed crystal orientation testing fixture for single-crystal blades includes the following steps:

[0016] Step 1: Clamping and fixing the seed crystal

[0017] First, insert the cut seed crystals one by one into the seed crystal slot. Then, place the pressure plate above the seed crystal slot, so that the rubber pad is between the seed crystal and the pressure plate. Then tighten the two clamping screws until the pressure plate presses and fixes the seed crystal in the seed crystal slot through the rubber pad, thus forming a seed crystal clamping assembly.

[0018] Step 2: Surface treatment of seed crystals

[0019] Electrolytic polishing was used to electropolish the end face and side face of the seed crystal located outside the seed crystal slot;

[0020] Step 3: Primary dendrite orientation analysis and testing of seed crystals

[0021] First, the base is inserted into the crystal orientation analyzer. The base is positioned in the crystal orientation analyzer by the first and second reference planes. Then, the seed crystal clamping assembly is inserted into the crystal orientation analyzer and placed on the base, so that the clamping stage and the positioning block are in contact. The fifth reference plane of the clamping stage is in contact with the third reference plane of the base, and the sixth reference plane of the clamping stage is in contact with the fourth reference plane of the base. Then, the distance between the measuring head of the crystal orientation analyzer and the seed crystal is adjusted. Then, the primary dendrite orientation of the seed crystal end face is analyzed and tested by the crystal orientation analyzer.

[0022] Step 4: Secondary dendrite orientation analysis and testing of seed crystals

[0023] Adjust the placement orientation of the seed crystal clamping assembly on the base so that the clamping stage and the positioning block are close together, the fifth reference surface of the clamping stage is in contact with the fourth reference surface of the base, and the sixth reference surface of the clamping stage is in contact with the third reference surface of the base. Then, readjust the distance between the measuring head of the crystal orientation analyzer and the seed crystal, and then analyze and test the secondary dendrite orientation on the side of the seed crystal using the crystal orientation analyzer.

[0024] The beneficial effects of this invention are:

[0025] The single-crystal blade seed crystal orientation testing fixture and its usage method of the present invention can meet the needs of batch electrolytic polishing of seed crystals, and at the same time meet the requirements of batch analysis and testing of seed crystal orientation, which can significantly improve the preparation efficiency of seed crystals, thereby better meeting the actual production schedule requirements. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the structure of a seed crystal orientation testing fixture for a single crystal blade according to the present invention;

[0027] Figure 2 This is a schematic diagram of the structure of the seed crystal clamping assembly of the present invention;

[0028] Figure 3 This is a schematic diagram of the clamping stage of the present invention;

[0029] Figure 4 This is a schematic diagram of the base of the present invention (view 1);

[0030] Figure 5 This is a schematic diagram of the base of the present invention (perspective two);

[0031] In the diagram, 1—base, 2—clamping platform, 3—pressure plate, 4—clamping screw, 5—seed crystal, 6—first support arm, 7—second support arm, 8—first reference surface, 9—second reference surface, 10—third reference surface, 11—fourth reference surface, 12—seed crystal slot, 13—fifth reference surface, 14—sixth reference surface, 15—rubber pad, 16—positioning block, 17—fastening screw. Detailed Implementation

[0032] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0033] like Figures 1-5 As shown, a seed crystal orientation testing fixture for single crystal blades includes a base 1, a clamping platform 2, a pressure plate 3, and a clamping screw 4; the clamping platform 2 is placed on the base 1; the clamping platform 2 is used to place the seed crystal 5; the pressure plate 3 is located above the seed crystal 5; the clamping screw 4 is vertically installed on the clamping platform 2 above the pressure plate 3.

[0034] The base 1 adopts an L-shaped structure. The two support arms of the base 1 are respectively referred to as the first support arm 6 and the second support arm 7. The end face of the first support arm 6 is designated as the first reference surface 8, the outer surface of the first support arm 6 is designated as the second reference surface 9, and the inner surface of the first support arm 6 is designated as the third reference surface 10. The inner surface of the second support arm 7 is designated as the fourth reference surface 11.

[0035] The clamping platform 2 adopts an inverted T-shaped groove structure. Several seed crystal slots 12 are evenly distributed on the bottom surface of the inverted T-shaped groove of the clamping platform 2, and one end of the seed crystal 5 is located in the seed crystal slot 12.

[0036] The lower surface of the clamping platform 2 is designated as the fifth reference surface 13, and the back surface of the clamping platform 2 is designated as the sixth reference surface 14.

[0037] The pressure plate 3 is located in the inverted T-shaped groove of the clamping platform 2 and directly above the seed crystal slot 12. A rubber pad 15 is fixedly attached to the lower surface of the pressure plate 3.

[0038] There are two clamping screws 4. Each of the two clamping arms at the top of the inverted T-shaped groove of the clamping platform 2 is equipped with a clamping screw 4. The screw end of the clamping screw 4 is directly opposite the upper surface of the pressure plate 3.

[0039] A positioning block 16 is provided on the back of the clamping table 2, and the positioning block 16 is fixedly connected to the clamping table 2 by fastening screws 17.

[0040] The method of using the seed crystal orientation testing fixture for single-crystal blades includes the following steps:

[0041] Step 1: Clamping and fixing seed crystal 5

[0042] First, insert the cut seed crystals 5 one by one into the seed crystal slot 12. Then, place the pressure plate 3 above the seed crystal slot 12 so that the rubber pad 15 is between the seed crystal 5 and the pressure plate 3. Then tighten the two clamping screws 4 until the pressure plate 3 presses and fixes the seed crystal 5 in the seed crystal slot 12 through the rubber pad 15, thus forming a seed crystal 5 clamping assembly.

[0043] In this embodiment, the seed crystal 5 is prepared by electrical discharge machining. The cut seed crystal 5 has a square cross-sectional shape with a side length of 3mm and a length of 30mm. The cross-sectional shape of the seed crystal slot 12 is designed to be adapted to the seed crystal 5. The insertion depth of the seed crystal 5 in the seed crystal slot 12 is 5mm, and the length of the seed crystal 5 remaining outside the seed crystal slot 12 is 25mm.

[0044] Step 2: Surface treatment of seed crystal 5

[0045] Electrolytic polishing was used to electropolish the end face and side face of the seed crystal 5 located outside the seed crystal slot 12;

[0046] In this embodiment, the voltage for electropolishing is 30V, the current for electropolishing is 10mA, the time for electropolishing is 10s, and the electrolyte used for electropolishing is a saturated sodium chloride aqueous solution. The side and end faces of the polished seed crystal 5 should exhibit a metallic luster in order to meet the requirements for subsequent analysis and testing of the orientation of the seed crystal 5.

[0047] Step 3: Primary dendrite orientation analysis and testing of seed crystal 5

[0048] First, the base 1 is sent into the crystal orientation analyzer. The base 1 is positioned in the crystal orientation analyzer by the first reference surface 8 and the second reference surface 9. Then, the seed crystal 5 clamping assembly is sent into the crystal orientation analyzer and placed on the base 1, so that the clamping stage 2 and the positioning block 16 are close together, so that the fifth reference surface 13 of the clamping stage 2 is in contact with the third reference surface 10 of the base 1, and so that the sixth reference surface 14 of the clamping stage 2 is in contact with the fourth reference surface 11 of the base 1. Then, the distance between the measuring head of the crystal orientation analyzer and the seed crystal 5 is adjusted, and then the primary dendrite orientation of the end face of the seed crystal 5 is analyzed and tested by the crystal orientation analyzer.

[0049] Step 4: Secondary dendrite orientation analysis and testing of seed crystal 5

[0050] Adjust the placement orientation of the seed crystal 5 clamping assembly on the base 1 so that the clamping stage 2 and the positioning block 16 are close together, the fifth reference surface 13 of the clamping stage 2 is in contact with the fourth reference surface 11 of the base 1, and the sixth reference surface 14 of the clamping stage 2 is in contact with the third reference surface 10 of the base 1. Then, readjust the distance between the measuring head of the crystal orientation analyzer and the seed crystal 5, and then analyze and test the secondary dendrite orientation on the side of the seed crystal 5 using the crystal orientation analyzer.

[0051] The solutions in the embodiments are not intended to limit the scope of protection of the present invention. All equivalent implementations or modifications that do not depart from the present invention are included in the scope of protection of the present invention.

Claims

1. A seed crystal orientation testing fixture for single-crystal blades, characterized in that: The system includes a base, a clamping platform, a pressure plate, and clamping screws. The clamping platform is placed on the base. A seed crystal is placed inside the clamping platform. The pressure plate is located above the seed crystal. The clamping screws are vertically installed on the clamping platform above the pressure plate. The base has an L-shaped structure, with two supporting arms designated as the first arm and the second arm. The end face of the first arm is designated as the first reference surface, the outer surface of the first arm as the second reference surface, and the inner surface of the first arm as the third reference surface. The inner surface of the second arm is designated as the fourth reference surface. The clamping platform has an inverted T-shaped groove structure. The bottom surface of the T-shaped groove is evenly spaced with several seed crystal slots, one end of the seed crystal being located within the seed crystal slot; the lower surface of the clamping platform is designated as the fifth reference surface, and the back surface of the clamping platform is designated as the sixth reference surface; the pressure plate is located within the inverted T-shaped groove of the clamping platform and directly above the seed crystal slot, with a rubber pad fixedly attached to the lower surface of the pressure plate; there are two clamping screws, one on each of the two clamping arms at the top of the inverted T-shaped groove of the clamping platform, with the screw end facing the upper surface of the pressure plate; a positioning block is provided on the back surface of the clamping platform, and the positioning block is fixedly connected to the clamping platform by fastening screws.

2. The method of using the seed crystal orientation testing fixture for single-crystal blades as described in claim 1, characterized in that, Includes the following steps: Step 1: Clamping and fixing the seed crystal First, insert the cut seed crystals one by one into the seed crystal slot. Then, place the pressure plate above the seed crystal slot, so that the rubber pad is between the seed crystal and the pressure plate. Then tighten the two clamping screws until the pressure plate presses and fixes the seed crystal in the seed crystal slot through the rubber pad, thus forming a seed crystal clamping assembly. Step 2: Surface treatment of seed crystals Electrolytic polishing was used to electropolish the end face and side face of the seed crystal located outside the seed crystal slot; Step 3: Primary dendrite orientation analysis and testing of the seed crystal First, the base is inserted into the crystal orientation analyzer. The base is positioned in the crystal orientation analyzer by the first and second reference planes. Then, the seed crystal clamping assembly is inserted into the crystal orientation analyzer and placed on the base, so that the clamping stage and the positioning block are in contact. The fifth reference plane of the clamping stage is in contact with the third reference plane of the base, and the sixth reference plane of the clamping stage is in contact with the fourth reference plane of the base. Then, the distance between the measuring head of the crystal orientation analyzer and the seed crystal is adjusted. Then, the primary dendrite orientation of the seed crystal end face is analyzed and tested by the crystal orientation analyzer. Step 4: Secondary dendrite orientation analysis and testing of seed crystals Adjust the placement orientation of the seed crystal clamping assembly on the base so that the clamping stage and the positioning block are close together, the fifth reference surface of the clamping stage is in contact with the fourth reference surface of the base, and the sixth reference surface of the clamping stage is in contact with the third reference surface of the base. Then, readjust the distance between the measuring head of the crystal orientation analyzer and the seed crystal, and then analyze and test the secondary dendrite orientation on the side of the seed crystal using the crystal orientation analyzer.

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