Method for precisely repairing blade through laser fuse based on synchronous coordination of workpiece swing and energy dynamic regulation and control

Abstract

The invention discloses a laser fuse precise blade repairing method based on synchronous coordination of workpiece swing and energy dynamic regulation and control, and belongs to the technical field of aero-engine and gas turbine blade repairing. The problems that incomplete fusion and sinking are prone to occurring in existing conventional laser repairing high-temperature alloy blades, and due to the fact that precise control cannot be achieved in variable-power laser repairing high-temperature alloy blades, repairing positions are ablated, and a base body deforms are solved. The method comprises the following steps: 1, fixing turbine blades; 2, setting parameters; 3, laser welding dynamic regulation and control repair; and 4, machining. The method is used for precisely repairing the blade through the laser fuse based on synchronous coordination of workpiece swing and energy dynamic regulation and control.

Description

Technical Field

[0001] The invention belongs to the technical field of aircraft engine and gas turbine blade repair. Background Art

[0002] Some turbine blades of aircraft engines and gas turbines are cast with high-temperature alloys, such as rotor blades, guide vanes and other high-temperature parts that serve at 1000°C. Their serrated crown structure can improve turbine performance. Turbine blades are extremely susceptible to damage in high-temperature, high-speed impact and corrosion environments for a long time, mainly concentrated in the blade body and serrated crown, including bending deformation, corrosion points, pits, cracks, etc., among which the blade crown is prone to wear and cracks. Since high-temperature alloys contain more elements such as Al and Ti, dense oxides such as Al and Ti will form on the surface of the fatigue cracks produced. Mechanical cleaning methods are required to remove the oxide film and inclusions on the defective surface. The cost of replacing new blades is high, so repairing damaged blades helps to achieve multi-cycle long-life reuse of blades, which has extremely high economic benefits.

[0003] At present, manual argon arc welding is mostly used in blade repair processes, and CoCrW welding wire is a commonly used material in blade repair. The heat source area of ​​manual argon arc welding is large, and the heat-affected zone is large, so cracks and other defects are easily generated during the blade repair process; at the same time, argon arc welding is also limited by the size of the blade when repairing turbine blades. Excessive heat input will cause deformation of the blade repair part and reduce material reliability.

[0004] As a repair technology, laser additive manufacturing uses laser as a heat source to apply heat input to the base material and filler material (powder or wire) to melt and combine, and then cool and solidify rapidly to form a weld overlay. At present, laser powder cladding can achieve precise repair of turbine blade serration surface wear, sealing tooth wear or cracks. However, the difficulty of densification of laser powder deposition itself greatly restricts its application in blade damage repair. At the same time, the overall thickness of the damaged part of the blade is inconsistent. The conventional laser repair technology has the problem of inconsistent matching between the laser power and the thickness of the repaired part, which is prone to defects such as unfused or pits. Therefore, variable power is generally used for processing, but the blade repair forming is still difficult to control accurately, and problems such as ablation of the repair position of the repaired blade and deformation of the substrate often occur. Summary of the invention

[0005] The present invention aims to solve the problems that conventional laser repair of high-temperature alloy blades is prone to unfusion and depression, and variable-power laser repair of high-temperature alloy blades cannot be precisely controlled, resulting in ablation of the repair position and deformation of the substrate, and further provides a method for precise blade repair with laser fuse based on the synchronous coordination of workpiece swing and dynamic energy regulation.

[0006] A method for laser fuse precision repair of blades based on synchronous coordination of workpiece swing and energy dynamic regulation is carried out in the following steps:

[0007] 1. Fixing turbine blades:

[0008] Fix the turbine blade with damaged interlocking surface on the CNC machine tool by a fixture, and keep the angle between the interlocking surface and the horizontal plane of the CNC machine tool at 20° to 30°, and the short side of the interlocking surface is parallel to the X-axis;

[0009] 2. Parameter settings:

[0010] The turbine blade with damaged interlocking surface is set to swing along the X-axis of the CNC machine tool, and the swing speed is 400 mm / min to 1000 mm / min; the swing amplitude of the turbine blade with damaged interlocking surface along the X-axis of the CNC machine tool is set to be l, and the short side length of the interlocking surface is set to be L, L>l; the laser beam is set to move along the Y-axis of the CNC machine tool;

[0011] 3. Laser welding dynamic control and repair:

[0012] Under the conditions that the swing speed of the turbine blade with interlocking surface damage is 400mm / min~1000mm / min, the swing amplitude of the turbine blade with interlocking surface damage is l, the laser beam moving speed is 0.06m / min~0.1m / min and the wire feeding speed is 0.6m / min~0.96m / min, the interlocking surface is repaired by laser welding dynamic control using welding wire to obtain a repaired blade;

[0013] The laser welding dynamic control repair is specifically carried out according to the following steps:

[0014] ① Taking the concave R zone where the interlocking surface and the non-working surface are connected as the starting point, under the conditions that the laser beam output power is 600W to 800W and the focal length of the laser beam on the interlocking surface is +2mm to +3mm, the laser beam stays in the concave R zone where the interlocking surface and the non-working surface are connected for 0.5s to 1.0s;

[0015] ② Under the conditions that the laser beam output power is 550W to 650W and the focal length of the laser beam on the interlocking surface is +2mm to +3mm, the laser beam moves on the interlocking surface until it reaches 1.5mm to 2mm from the end of the interlocking surface;

[0016] ③ When the laser beam output power is 550W to 650W and the focal length of the laser beam on the interlocking surface is +2mm to +3mm, the laser beam stays at a distance of 1.5mm to 2mm from the end of the interlocking surface for 0.4s to 0.6s;

[0017] ④ Reduce the laser power. When the laser beam output power is 500W to 600W and the focal length of the laser beam on the interlocking surface is +2mm to +3mm, the laser beam moves on the interlocking surface until it reaches the end of the interlocking surface.

[0018] ⑤ When the laser beam output power is 500W to 600W and the focal length of the laser beam on the interlocking surface is +2mm to +3mm, the laser beam stays at the end of the interlocking surface for 0.4s to 0.6s;

[0019] ⑥ When the laser beam output power is 500W to 600W, lift the laser head along the Z axis until the focal length of the laser beam on the interlocking surface is +3mm to +4mm, and then when the laser beam output power is 500W to 600W and the focal length of the laser beam on the interlocking surface is +3mm to +4mm, the laser beam stays at the end of the interlocking surface for 0.4s to 0.6s;

[0020] ⑦ Under the condition that the laser beam output power is 500W to 600W, lift the laser head along the Z axis for the second time, then turn off the CNC machine tool and the laser, and take out the repaired blade;

[0021] 4. Mechanical processing:

[0022] The interlocking surfaces of the repaired blades are mechanically processed to restore their original appearance, thus completing a method for precision blade repair with laser fuse based on synchronous coordination of workpiece swing and dynamic energy regulation.

[0023] The beneficial effects of the present invention are:

[0024] The preparation method for laser fuse blade repair based on the synchronous coordination of workpiece swing and dynamic energy regulation is to fix the blade on a specific fixture, and then use a CNC machine tool to swing the turbine blade with damaged interlocking surface along the X-axis direction to increase the scanning area during the laser fuse repair process. The dynamic adjustment refers to the dynamic change of the laser beam output power in different areas of the surface of the blade repair position during the laser fuse process. At the same time, the laser beam is paused at different repair positions to compensate for the unstable fusion problem caused by variable power during the fuse process. For laser fuse repair of interlocking surface wear, it is necessary to lift the laser head at the end of the repair position so that the repair position reaches a certain thickness to form a coated weld layer.

[0025] The main advantages of using this method to repair turbine blades are as follows:

[0026] 1. Using CNC machine tools to swing the turbine blades with damaged interlocking surfaces can increase the scanning area during laser welding, reduce the number of welding times, avoid problems such as poor fusion that are prone to occur under multiple welding paths, and precisely repair the damaged parts of the blades. At the same time, the swing amplitude can be changed according to the different blade models and sizes, and different damaged parts on the blades can be repaired, which is more adaptable;

[0027] 2. Dynamic energy adjustment: By controlling the output of laser beam power and changing the defocus, the overall morphology of the surfacing layer at the repair position is shaped, solving problems such as lack of fusion, depression, ablation at the repair position and substrate deformation. At the same time, the gradient power can repair blades of various models, which helps to obtain a well-formed surfacing layer and improve the repair quality and qualified rate of the blade repair position;

[0028] 3. Compared with the swing laser wire feeding, the swing of the workpiece can make the laser beam act evenly on the base material and the wire, ensuring the consistent energy distribution on the base material and the wire. The swing laser fuse repair realizes the swing of the beam by the swing of the galvanometer, and the beam energy distribution cannot be consistent, which easily causes the fuse to be unstable during the repair process.

[0029] 4. Compared with traditional argon arc welding and laser powder feeding repair, the weld layer at the blade repair position of laser fuse repair is closely integrated with the base material, there are no defects at the interface, the structure is more uniform, there are no cracks, pores and other defects inside the weld layer, and the thickness of the weld layer reaches 3mm, leaving a certain margin for subsequent mechanical processing.

[0030] The present invention is used for a method for laser fuse precision repairing blades based on synchronous coordination of workpiece swing and energy dynamic regulation. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 This is a schematic diagram of the structure of a turbine blade with damaged interlocking surface as described in step 1 of the present invention, 1 is the tenon, 2 is the blade body, 3 is the serration crown, and 4 is the sealing tooth;

[0032] Figure 2 This is a partial enlarged top view of a turbine blade serration crown with damaged interlocking surface as described in step 1 of the present invention, 5 is the interlocking surface; 6 is the concave R area where the interlocking surface and the non-working surface are connected;

[0033] Figure 3 This is a partial enlarged view of the damaged position of the interlocking surface of the turbine blade serration crown with damaged interlocking surface as described in step 1 of the present invention, 4 is the sealing tooth, 7 is the damaged position of the interlocking surface, and 8 is the end of the interlocking surface;

[0034] Figure 4 Schematic diagram of power and path of laser fuse precision repair of blades based on synchronous coordination of workpiece swing and energy dynamic control in Example 1, t0-t1 is the laser beam dwell time in step 3 ①, t1-t2 is the laser beam travel and dwell time in steps 3 ② and ③, t2-t3 is the laser beam travel and dwell time in steps 3 ④ to ⑦;

[0035] Figure 5Schematic diagram of laser fuse repair of a swinging workpiece in a CNC machine tool for laser fuse precision repair of a blade based on synchronous coordination of workpiece swing and energy dynamic regulation in Example 1, 9 is a CNC machine tool, 10 is an interlocking surface, and 11 is a laser beam;

[0036] Figure 6 This is Example 1, which shows the surface and cross-sectional morphology of the surfacing layer at the repair position after the laser fuse precision repair of the blade based on the synchronous coordination of the workpiece swing and the dynamic energy regulation. DETAILED DESCRIPTION

[0037] Specific implementation method 1, combined with Figures 1 to 3 Specific analysis: This embodiment is a method for laser fuse precision repair of blades based on synchronous coordination of workpiece swing and energy dynamic regulation, which is carried out in the following steps:

[0038] 1. Fixing turbine blades:

[0039] Fix the turbine blade with damaged interlocking surface on the CNC machine tool by a fixture, and keep the angle between the interlocking surface and the horizontal plane of the CNC machine tool at 20° to 30°, and the short side of the interlocking surface is parallel to the X-axis;

[0040] 2. Parameter settings:

[0041] The turbine blade with damaged interlocking surface is set to swing along the X-axis of the CNC machine tool, and the swing speed is 400 mm / min to 1000 mm / min; the swing amplitude of the turbine blade with damaged interlocking surface along the X-axis of the CNC machine tool is set to be l, and the short side length of the interlocking surface is set to be L, L>l; the laser beam is set to move along the Y-axis of the CNC machine tool;

[0042] 3. Laser welding dynamic control and repair:

[0043] Under the conditions that the swing speed of the turbine blade with interlocking surface damage is 400mm / min~1000mm / min, the swing amplitude of the turbine blade with interlocking surface damage is l, the laser beam moving speed is 0.06m / min~0.1m / min and the wire feeding speed is 0.6m / min~0.96m / min, the interlocking surface is repaired by laser welding dynamic control using welding wire to obtain a repaired blade;

[0044] The laser welding dynamic control repair is specifically carried out according to the following steps:

[0045] ① Taking the concave R zone where the interlocking surface and the non-working surface are connected as the starting point, under the conditions that the laser beam output power is 600W to 800W and the focal length of the laser beam on the interlocking surface is +2mm to +3mm, the laser beam stays in the concave R zone where the interlocking surface and the non-working surface are connected for 0.5s to 1.0s;

[0046] ② Under the conditions that the laser beam output power is 550W to 650W and the focal length of the laser beam on the interlocking surface is +2mm to +3mm, the laser beam moves on the interlocking surface until it reaches 1.5mm to 2mm from the end of the interlocking surface;

[0047] ③ When the laser beam output power is 550W to 650W and the focal length of the laser beam on the interlocking surface is +2mm to +3mm, the laser beam stays at a distance of 1.5mm to 2mm from the end of the interlocking surface for 0.4s to 0.6s;

[0048] ④ Reduce the laser power. When the laser beam output power is 500W to 600W and the focal length of the laser beam on the interlocking surface is +2mm to +3mm, the laser beam moves on the interlocking surface until it reaches the end of the interlocking surface.

[0049] ⑤ When the laser beam output power is 500W to 600W and the focal length of the laser beam on the interlocking surface is +2mm to +3mm, the laser beam stays at the end of the interlocking surface for 0.4s to 0.6s;

[0050] ⑥ When the laser beam output power is 500W to 600W, lift the laser head along the Z axis until the focal length of the laser beam on the interlocking surface is +3mm to +4mm, and then when the laser beam output power is 500W to 600W and the focal length of the laser beam on the interlocking surface is +3mm to +4mm, the laser beam stays at the end of the interlocking surface for 0.4s to 0.6s;

[0051] ⑦ Under the condition that the laser beam output power is 500W to 600W, lift the laser head along the Z axis for the second time, then turn off the CNC machine tool and the laser, and take out the repaired blade;

[0052] 4. Mechanical processing:

[0053] The interlocking surfaces of the repaired blades are mechanically processed to restore their original appearance, thus completing a method for precision blade repair with laser fuse based on synchronous coordination of workpiece swing and dynamic energy regulation.

[0054] In step one of the present specific implementation method, the damaged area of ​​the serrated crown of the high-temperature alloy turbine blade is first inspected for damage to determine the types of wear and crack defects, the blades with worn interlocking surfaces are picked out, and the blades with damaged interlocking surfaces are polished and cleaned with minimal grinding loss to the substrate. During repair, the entire interlocking surface is mechanically cleaned and repaired regardless of the size of the damaged area of ​​the interlocking surface.

[0055] In steps 3 ⑥ and ⑦ of this specific implementation method, the laser head is lifted along the Z axis in order to repair the end of the damaged surface and ensure that there is a certain processing allowance at the end, and also to prevent ablation problems caused by excessive heat input at the end.

[0056] The beneficial effects of this specific implementation are:

[0057] The preparation method for laser fuse blade repair based on the synchronous coordination of workpiece swing and dynamic energy regulation is to fix the blade on a specific fixture, and then use a CNC machine tool to swing the turbine blade with damaged interlocking surface along the X-axis direction to increase the scanning area during the laser fuse repair process. The dynamic adjustment refers to the dynamic change of the laser beam output power in different areas of the surface of the blade repair position during the laser fuse process. At the same time, the laser beam is paused at different repair positions to compensate for the unstable fusion problem caused by variable power during the fuse process. For laser fuse repair of interlocking surface wear, it is necessary to lift the laser head at the end of the repair position so that the repair position reaches a certain thickness to form a coated weld layer.

[0058] The main advantages of using this method to repair turbine blades are as follows:

[0059] 1. Using CNC machine tools to swing the turbine blades with damaged interlocking surfaces can increase the scanning area during laser welding, reduce the number of welding times, avoid problems such as poor fusion that are prone to occur under multiple welding paths, and precisely repair the damaged parts of the blades. At the same time, the swing amplitude can be changed according to the different blade models and sizes, and different damaged parts on the blades can be repaired, which is more adaptable;

[0060] 2. Dynamic energy adjustment: By controlling the output of laser beam power and changing the defocus, the overall morphology of the surfacing layer at the repair position is shaped, solving problems such as lack of fusion, depression, ablation at the repair position and substrate deformation. At the same time, the gradient power can repair blades of various models, which helps to obtain a well-formed surfacing layer and improve the repair quality and qualified rate of the blade repair position;

[0061] 3. Compared with the swing laser wire feeding, the swing of the workpiece can make the laser beam act evenly on the base material and the wire, ensuring the consistent energy distribution on the base material and the wire. The swing laser fuse repair realizes the swing of the beam by the swing of the galvanometer, and the beam energy distribution cannot be consistent, which easily causes the fuse to be unstable during the repair process.

[0062] 4. Compared with traditional argon arc welding and laser powder feeding repair, the weld layer at the blade repair position of laser fuse repair is closely integrated with the base material, there are no defects at the interface, the structure is more uniform, there are no cracks, pores and other defects inside the weld layer, and the thickness of the weld layer reaches 3mm, leaving a certain margin for subsequent mechanical processing.

[0063] Specific implementation method 2: This implementation method is different from specific implementation method 1 in that the material of the turbine blade with damaged interlocking surface in step 1 is DZ125 alloy. The rest is the same as specific implementation method 1.

[0064] Specific implementation method three: This implementation method is different from specific implementation method one or two in that: the turbine blade with damaged interlocking surface in step one is a pre-treated turbine blade; the pre-treatment is specifically carried out in the following steps: in an argon environment, the turbine blade is polished and cleaned to remove the damaged surface oxide film, and then the interlocking surface and the surrounding position are wiped with anhydrous ethanol and acetone in turn, and finally dried to reveal the metallic luster. The rest is the same as specific implementation method one or two.

[0065] Specific implementation mode 4: This implementation mode is different from specific implementation modes 1 to 3 in that: in step 2, L1=0.4 mm to 0.6 mm. The rest is the same as specific implementation modes 1 to 3.

[0066] Specific implementation example 5: This implementation example is different from specific implementation examples 1 to 4 in that in step 2, the laser head is set at an angle of 5° to 10° with the interlocking surface. The rest is the same as specific implementation examples 1, 2 to 4.

[0067] Specific implementation example 6: This implementation example is different from specific implementation examples 1 to 5 in that the welding wire described in step 3 is CoCrW welding wire. The rest is the same as specific implementation examples 1 to 5.

[0068] Specific embodiment 7: This embodiment is different from specific embodiments 1 to 6 in that the diameter of the welding wire in step 3 is 1.0 mm to 1.2 mm. The rest is the same as specific embodiments 1 to 6.

[0069] Specific embodiment 8: This embodiment is different from specific embodiments 1 to 7 in that the welding wire described in step 3 is a pre-treated welding wire; the pre-treatment is specifically carried out in the following steps: using 400-grit sandpaper to grind it smooth, then wiping it with anhydrous ethanol and drying it. The rest is the same as specific embodiments 1 to 7.

[0070] Specific embodiment 9: This embodiment is different from any one of specific embodiments 1 to 8 in that: in step 3, under the conditions that the swing speed of the turbine blade with interlocking surface damage is 400 mm / min to 1000 mm / min, the swing amplitude of the turbine blade with interlocking surface damage is 1, the laser beam moving speed is 0.06 m / min to 0.1 m / min, the wire feeding speed is 0.6 m / min to 0.96 m / min, and the argon shielding gas flow rate is 15 L / min to 20 L / min, the interlocking surface is laser welded dynamically regulated and repaired using welding wire to obtain a repaired blade. The rest is the same as specific embodiments 1 to 8.

[0071] Specific embodiment 10: This embodiment differs from specific embodiments 1 to 9 in that: in step 3 (7), under the condition that the laser beam output power is 500W to 600W, the laser head is lifted for the second time along the Z axis until the focal length of the laser beam on the interlocking surface is +4mm to +5mm, and then the CNC machine tool and the laser are turned off, and the repaired blade is taken out. The rest is the same as specific embodiments 1 to 9.

[0072] The following examples are used to verify the beneficial effects of the present invention:

[0073] Embodiment 1, combined with Figure 4 and Figure 5 Specific instructions:

[0074] A method for laser fuse precision repair of blades based on synchronous coordination of workpiece swing and energy dynamic regulation is carried out in the following steps:

[0075] 1. Fixing turbine blades:

[0076] The turbine blade with damaged interlocking surface is fixed on the CNC machine tool by a fixture, and the interlocking surface is kept at an angle of 25° with the horizontal plane of the CNC machine tool, and the short side of the interlocking surface is parallel to the X-axis;

[0077] 2. Parameter settings:

[0078] The turbine blade with damaged interlocking surface is set to swing along the X-axis of the CNC machine tool, and the swing speed is 600 mm / min; the swing amplitude of the turbine blade with damaged interlocking surface along the X-axis of the CNC machine tool is set to l, and the short side length of the interlocking surface is set to L=4.5 mm, l=4 mm, Ll=0.5 mm; the laser beam is set to move along the Y-axis of the CNC machine tool;

[0079] 3. Laser welding dynamic control and repair:

[0080] Under the conditions of the turbine blade swing speed of 600mm / min, the turbine blade swing amplitude of 4mm, the laser beam moving speed of 0.06m / min, the wire feeding speed of 0.72m / min and the argon shielding gas flow rate of 18L / min, the interlocking surface was repaired by laser welding dynamic control using welding wire to obtain a repaired blade.

[0081] The laser welding dynamic control repair is specifically carried out according to the following steps:

[0082] ① Taking the concave R zone where the interlocking surface and the non-working surface transition as the starting point, under the conditions that the laser beam output power is 650W and the focal length of the laser beam on the interlocking surface is +2mm, the laser beam stays in the concave R zone where the interlocking surface and the non-working surface transition for 0.5s;

[0083] ② Under the conditions that the laser beam output power is 600W and the focal length of the laser beam on the interlocking surface is +2mm, the laser beam moves on the interlocking surface until it reaches 2mm from the end of the interlocking surface;

[0084] ③ Under the conditions that the laser beam output power is 600W and the focal length of the laser beam on the interlocking surface is +2mm, the laser beam stays at a distance of 2mm from the end of the interlocking surface for 0.5s;

[0085] ④ Reduce the laser power. Under the conditions that the laser beam output power is 500W and the focal length of the laser beam on the interlocking surface is +2mm, the laser beam moves on the interlocking surface until it reaches the end of the interlocking surface;

[0086] ⑤ Under the conditions that the laser beam output power is 500W and the focal length of the laser beam on the interlocking surface is +2mm, the laser beam stays at the end of the interlocking surface for 0.5s;

[0087] ⑥ Under the condition that the laser beam output power is 500W, lift the laser head along the Z axis until the focal length of the laser beam on the interlocking surface is +3mm, and then under the condition that the laser beam output power is 500W and the focal length of the laser beam on the interlocking surface is +3mm, the laser beam stays at the end of the interlocking surface for 0.5s;

[0088] ⑦ Under the condition that the laser beam output power is 500W, lift the laser head along the Z axis for the second time until the focal length of the laser beam on the interlocking surface is +4mm, then turn off the CNC machine tool and the laser, and take out the repaired blade;

[0089] 4. Mechanical processing:

[0090] The interlocking surfaces of the repaired blades are mechanically processed to restore their original appearance, thus completing a method for precision blade repair with laser fuse based on synchronous coordination of workpiece swing and dynamic energy regulation.

[0091] The material of the turbine blade with interlocking surface damage described in step 1 is DZ125 alloy, which is a directionally solidified high-temperature alloy. The high-pressure and high-temperature service environment causes corrosion, oxidation, thermal fatigue and mechanical fatigue of the turbine blades and nozzles. Since it contains more elements such as Al and Ti, dense oxides such as Al and Ti will be formed on the surface of the fatigue cracks. Mechanical cleaning methods are required to remove the oxide film and inclusions on the defective surface.

[0092] The turbine blade with damaged interlocking surface described in step one is a pretreated turbine blade; the pretreatment is specifically carried out according to the following steps: in an argon environment, the turbine blade is polished and cleaned to remove the oxide film on the damaged surface, and then the damaged surface and the surrounding area are wiped with anhydrous ethanol and acetone in turn, and finally dried to reveal the metallic luster.

[0093] In step 2, the laser head is set at an angle of 10° to the interlocking surface.

[0094] The welding wire described in step three is a CoCrW welding wire, and the CoCrW welding wire is composed of 29.64% C, 1.15% C, 4.12% W and the balance Co in mass percentage.

[0095] The diameter of the welding wire described in step 3 is 1.0 mm.

[0096] The welding wire described in step three is a pretreated welding wire; the pretreatment is specifically carried out according to the following steps: polishing it smooth with 400-mesh sandpaper, then wiping it with anhydrous ethanol and drying it.

[0097] Table 1 Example 1 Parameters of laser fuse precision blade repair based on synchronous coordination of workpiece swing and energy dynamic control

[0098]

[0099] Figure 6 This is Example 1, which shows the surface and cross-sectional morphology of the weld layer at the repair position after the blade is repaired by laser fuse based on the synchronous coordination of workpiece swing and energy dynamic regulation. As can be seen from the figure, the surface of the wear-resistant layer of the blade repaired by laser fuse based on the synchronous coordination of workpiece swing assistance and energy dynamic regulation is smooth, and the thickness of the weld layer reaches 3mm. The melting of the metal at the repair position can be accurately controlled by energy regulation to ensure that there is no burning on the left and right sides of the interlocking surface and the end of the repair position, no substrate deformation problem, and the interlocking surface and the non-working surface transition concave R zone are fused continuously without unfused and concave problems. The repaired wear-resistant layer has no defects such as cracks and pores, and the bonding strength between the weld layer and the base material is high. After milling, the surface of the weld layer is flat and smooth, and the transition with the base material is continuous and uniform, which meets the current usage standards. The process has good stability and can adapt to the repair of damaged parts of blades of various models with a high pass rate.

Claims

1. A method for precision blade repair by laser fuse based on synchronous coordination of workpiece swing and energy dynamic regulation. Features It is carried out in the following steps:

1. Fixing turbine blades: Fix the turbine blade with damaged interlocking surface on the CNC machine tool by a fixture, and keep the angle between the interlocking surface and the horizontal plane of the CNC machine tool at 20° to 30°, and the short side of the interlocking surface is parallel to the X-axis; 2. Parameter settings: The turbine blade with damaged interlocking surface is set to swing along the X-axis of the CNC machine tool, and the swing speed is 400 mm / min to 1000 mm / min; the swing amplitude of the turbine blade with damaged interlocking surface along the X-axis of the CNC machine tool is set to be l, and the short side length of the interlocking surface is set to be L, L>l; the laser beam is set to move along the Y-axis of the CNC machine tool; 3. Laser welding dynamic control and repair: Under the conditions that the swing speed of the turbine blade with interlocking surface damage is 400mm / min~1000mm / min, the swing amplitude of the turbine blade with interlocking surface damage is l, the laser beam moving speed is 0.06m / min~0.1m / min and the wire feeding speed is 0.6m / min~0.96m / min, the interlocking surface is repaired by laser welding dynamic control using welding wire to obtain a repaired blade; The laser welding dynamic control repair is specifically carried out according to the following steps: ① Taking the concave R zone where the interlocking surface and the non-working surface are connected as the starting point, under the conditions that the laser beam output power is 600W to 800W and the focal length of the laser beam on the interlocking surface is +2mm to +3mm, the laser beam stays in the concave R zone where the interlocking surface and the non-working surface are connected for 0.5s to 1.0s; ② Under the conditions that the laser beam output power is 550W to 650W and the focal length of the laser beam on the interlocking surface is +2mm to +3mm, the laser beam moves on the interlocking surface until it reaches 1.5mm to 2mm from the end of the interlocking surface; ③ When the laser beam output power is 550W to 650W and the focal length of the laser beam on the interlocking surface is +2mm to +3mm, the laser beam stays at a distance of 1.5mm to 2mm from the end of the interlocking surface for 0.4s to 0.6s; ④ Reduce the laser power. When the laser beam output power is 500W to 600W and the focal length of the laser beam on the interlocking surface is +2mm to +3mm, the laser beam moves on the interlocking surface until it reaches the end of the interlocking surface. ⑤ When the laser beam output power is 500W to 600W and the focal length of the laser beam on the interlocking surface is +2mm to +3mm, the laser beam stays at the end of the interlocking surface for 0.4s to 0.6s; ⑥ When the laser beam output power is 500W to 600W, lift the laser head along the Z axis until the focal length of the laser beam on the interlocking surface is +3mm to +4mm, and then when the laser beam output power is 500W to 600W and the focal length of the laser beam on the interlocking surface is +3mm to +4mm, the laser beam stays at the end of the interlocking surface for 0.4s to 0.6s; ⑦ Under the condition that the laser beam output power is 500W to 600W, lift the laser head along the Z axis for the second time, then turn off the CNC machine tool and the laser, and take out the repaired blade; 4. Mechanical processing: The interlocking surfaces of the repaired blades are mechanically processed to restore their original appearance, thus completing a method for precision blade repair with laser fuse based on synchronous coordination of workpiece swing and dynamic energy regulation.

2. According to claim 1, a method for precision repairing blades by laser fuse based on synchronous coordination of workpiece swing and energy dynamic regulation, Features The material of the turbine blade with damaged interlocking surface described in step 1 is DZ125 alloy.

3. According to claim 1, a method for precision repairing blades by laser fuse based on synchronous coordination of workpiece swing and energy dynamic regulation, Features The turbine blade with damaged interlocking surface described in step one is a pretreated turbine blade; the pretreatment is specifically carried out according to the following steps: in an argon environment, the turbine blade is polished and cleaned to remove the damaged surface oxide film, and then the interlocking surface and the surrounding position are wiped with anhydrous ethanol and acetone in turn, and finally dried to reveal the metallic luster.

4. According to claim 1, a method for precision repairing blades by laser fuse based on synchronous coordination of workpiece swing and energy dynamic regulation, Features In step 2, Ll=0.4mm~0.6mm.

5. According to claim 1, a method for precision repairing blades by laser fuse based on synchronous coordination of workpiece swing and energy dynamic regulation, Features In step 2, the laser head is set at an angle of 5° to 10° with the interlocking surface.

6. According to claim 1, a method for precision repairing blades by laser fuse based on synchronous coordination of workpiece swing and energy dynamic regulation, Features The welding wire described in step 3 is CoCrW welding wire.

7. According to claim 1, a method for precision repairing blades by laser fuse based on synchronous coordination of workpiece swing and energy dynamic regulation, Features The diameter of the welding wire described in step 3 is 1.0 mm to 1.2 mm.

8. According to claim 1, a method for precision blade repair by laser fuse based on synchronous coordination of workpiece swing and energy dynamic regulation, Features The welding wire described in step three is a pretreated welding wire; the pretreatment is specifically carried out according to the following steps: polishing it smooth with 400-mesh sandpaper, then wiping it with anhydrous ethanol and drying it.

9. According to claim 1, a method for precision repairing blades by laser fuse based on synchronous coordination of workpiece swing and energy dynamic regulation, Features In step three, under the conditions that the swing speed of the turbine blade with interlocking surface damage is 400mm / min~1000mm / min, the swing amplitude of the turbine blade with interlocking surface damage is l, the laser beam moving speed is 0.06m / min~0.1m / min, the wire feeding speed is 0.6m / min~0.96m / min and the argon shielding gas flow rate is 15L / min~20L / min, the interlocking surface is laser welded dynamically controlled and repaired using welding wire to obtain a repaired blade.

10. According to claim 1, a method for precision repairing blades by laser fuse based on synchronous coordination of workpiece swing and energy dynamic regulation, Features Step 3 ⑦: Under the condition that the laser beam output power is 500W to 600W, lift the laser head along the Z axis for the second time until the focal length of the laser beam on the interlocking surface is +4mm to +5mm, then turn off the CNC machine tool and the laser, and take out the repaired blade.

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