CN112853346B - Laser cladding remanufacturing device and remanufacturing method for railway vehicle axle - Google Patents
Laser cladding remanufacturing device and remanufacturing method for railway vehicle axle Download PDFInfo
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- CN112853346B CN112853346B CN202110023930.9A CN202110023930A CN112853346B CN 112853346 B CN112853346 B CN 112853346B CN 202110023930 A CN202110023930 A CN 202110023930A CN 112853346 B CN112853346 B CN 112853346B
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- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C24/00—Coating starting from inorganic powder
- C23C24/08—Coating starting from inorganic powder by application of heat or pressure and heat
- C23C24/10—Coating starting from inorganic powder by application of heat or pressure and heat with intermediate formation of a liquid phase in the layer
- C23C24/103—Coating with metallic material, i.e. metals or metal alloys, optionally comprising hard particles, e.g. oxides, carbides or nitrides
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Abstract
The invention relates to the technical field of railway vehicles, and provides a laser cladding remanufacturing device and a remanufacturing method for an axle of a railway vehicle, wherein the device comprises the following components: the device comprises a clamping mechanism, a cladding laser and an ultrasonic module; the clamping mechanism is used for clamping the axle to be repaired; the cladding laser is arranged corresponding to the part to be repaired of the axle to be repaired and is used for repairing the axle to be repaired; the ultrasonic module is arranged corresponding to the part to be repaired of the axle to be repaired and is used for impacting the surface of the base material of the axle to be repaired; and at least part of the surface of the base material is damaged by laser emitted by the cladding laser in the laser cladding remanufacturing process. According to the laser cladding remanufacturing device and the laser cladding remanufacturing method for the axle of the railway vehicle, provided by the invention, the ultrasonic waves are adopted to impact the surface of the base material of the axle to be repaired, and the distortion energy and the compressive stress are introduced into the position of the damaged area of the base material in advance, so that the problems of the coarsening of the structure and the residual tensile stress of the heat damaged layer of the base material are solved.
Description
Technical Field
The invention relates to the technical field of railway vehicles, in particular to a laser cladding remanufacturing device and a laser cladding remanufacturing method for an axle of a railway vehicle.
Background
The high-speed motor train unit needs to be checked and maintained every certain running period or mileage. When the wheels and the axles are disassembled, scratches are easily generated at the wheel seats, and the scratch depth exceeds the maintenance standard (generally 0.1mm), so that the wheels and the axles need to be scrapped. The laser cladding remanufacturing technology is a technology which takes waste parts with damage exceeding limit as remanufacturing blanks, takes the laser cladding technology as a repairing means, realizes the repair of the shape, the size and the performance of damaged positions by laser heating filling materials such as powder, wire materials and the like, and enables remanufactured products to achieve new product performance. Generally, the cost of laser cladding remanufactured products does not exceed 50% of new products, 60% of energy can be saved, 70% of materials can be saved, resource-saving and environment-friendly social construction is facilitated, and the national green cycle development requirements are met.
The laser cladding remanufactured axle can be divided into four areas, namely a cladding area, an interface layer, a substrate heat damage area and a substrate. The laser thermal field acts on the surface to be repaired, so that parent metal near the surface to be repaired is subjected to phase transformation to precipitate a martensite phase and coarsening the structure, and the performance of the remanufactured axle is seriously deteriorated. In addition, due to the cooling shrinkage effect of the cladding metal, residual tensile stress can be formed in the damaged area of the base material, and the fatigue performance of the remanufactured axle is reduced.
Disclosure of Invention
The invention provides a laser cladding remanufacturing device for a railway vehicle axle, which is used for solving the defects that in the prior art, the surface of a base material is damaged in the cladding remanufacturing process of laser on the base material, so that the base material at the position near the surface to be repaired of the base material generates texture coarsening, the performance of the remanufactured axle is seriously deteriorated and residual tensile stress is formed in the damaged area of the base material.
The invention further provides a laser cladding remanufacturing method of the railway vehicle axle, which is used for solving the defects that in the cladding remanufacturing process of the base material by laser in the prior art, the surface of the base material is damaged, the base material at the position near the surface to be repaired of the base material is coarsened in tissue, the performance of the remanufactured axle is seriously deteriorated and the residual tensile stress is formed in the damaged area of the base material.
According to a first aspect of the invention, a laser cladding remanufacturing device for a railway vehicle axle is provided, which comprises: the device comprises a clamping mechanism, a cladding laser and an ultrasonic module;
the clamping mechanism is used for clamping the axle to be repaired;
the cladding laser is arranged corresponding to the part to be repaired of the axle to be repaired and is used for repairing the axle to be repaired;
the ultrasonic module is arranged corresponding to the part to be repaired of the axle to be repaired and is used for impacting the surface of the base material of the axle to be repaired;
and at least part of the surface of the base material is damaged by laser emitted by the cladding laser in the laser cladding remanufacturing process.
According to an embodiment of the present invention, further comprising: and the cleaning laser is arranged close to the cladding laser along the circumferential direction of the axle to be repaired and is used for cleaning the surface of the base material of the axle to be repaired after being impacted by the ultrasonic module.
Specifically, this embodiment provides an implementation mode of laser cladding refabrication device, and through setting up the cleaning laser and carrying out the cleaning operation to the surface to be repaired after the ultrasonic impact, factors that influence laser cladding refabrication such as oxide, greasy dirt, dust are got rid of.
In an application scenario, the clamping mechanism is a lathe with a corresponding clamping structure, and the axle to be repaired is clamped on the lathe, and then the manipulator is used for lapping the cleaning laser. When laser cleaning is used as a single process, the time interval between cleaning operation and cladding operation is not more than 4h, so that the surface of the axle is prevented from being polluted again; the laser cleaning process parameters are as follows: the laser cleaning power is 100 to 500W, the laser cleaning speed is 0.01 to 0.03m/s, and the cleaning width is 10 to 30 mm.
In an application scene, the clamping mechanism is a lathe with a corresponding clamping structure, and the axle to be repaired is clamped on the lathe, and the cleaning laser and the cladding laser are coupled and arranged on the same fixed structure together, so that an integrated operation mode of cleaning and cladding simultaneously is realized.
In one application scenario, the laser line width emitted by the cleaning laser is in the range of 10mm to 30mm and is adjustable. The laser cleaning process parameters are as follows: the laser cleaning power is 100 to 500W, the laser cleaning speed is 0.01 to 0.03m/s, and the cleaning width is 10 to 30 mm.
According to an embodiment of the present invention, further comprising: the preheating module is arranged corresponding to the part to be repaired of the axle to be repaired and used for preheating the axle to be repaired.
Specifically, the embodiment provides another embodiment of a laser cladding remanufacturing device, and the preheating treatment is performed before laser cladding of the axle to be repaired, so that the cooling rate of the laser cladding can be reduced, and the problem of precipitation of hard and brittle martensite phase in the heat damage area of the substrate is solved. By implementing the laser cladding remanufacturing pretreatment method, the mechanical property of the laser cladding remanufactured axle is improved, and the service life of the remanufactured axle is prolonged.
It should be noted that, due to the cooling shrinkage effect of the clad metal, tensile stress is formed in the damaged region of the base material, and the fatigue performance of the remanufactured axle is reduced. The above problem makes the damaged layer of the substrate become a weak area of the remanufactured axle, which seriously affects the safety of use of the remanufactured axle. Aiming at the problem of substrate damage caused by laser cladding remanufacturing, the method can effectively solve the problems of precipitation of hard and brittle martensite phase, coarsening of tissue and residual tensile stress of a heat damage layer of the substrate by performing preheating treatment before laser cladding remanufacturing of the axle to be repaired, improve the mechanical property of the laser cladding remanufactured axle and prolong the service life of the remanufactured axle.
According to an embodiment of the invention, the preheating module comprises: a first pre-heating laser and a second pre-heating laser temperature sensor;
the first preheating laser and the second preheating laser are arranged opposite to each other in the radial direction of the repair axle.
Specifically, this embodiment provides an implementation mode of preheating the module, and radial relative setting first preheating laser and the second preheating laser of treating the repair axletree, this kind of mode is symmetrical two preheating, can effectively avoid the stress problem that refabrication axletree preheats inhomogeneous production through symmetrical two preheating.
Further, the surface to be repaired is heated using a laser as a heat source, and the temperature of the heated surface is measured using a temperature sensor (e.g., an infrared induction thermometer). And heating the position to be repaired of the axle to be repaired to 100-300 ℃, and further reducing the cooling speed of laser cladding. The precipitation of martensite phase in the damaged area of the base material is avoided.
In an application scenario, the temperature sensor includes a first sensor and a second sensor, the first sensor is disposed corresponding to the first preheating laser, and the second sensor is disposed corresponding to the second preheating laser.
It should be noted that, because the laser preheating range is small and the cooling speed is fast, the preheating laser and the cladding laser need to be integrated, so as to realize the integrated operation mode of simultaneous preheating and simultaneous cladding.
In one application scenario, semiconductor lasers are used as emission sources of the first preheating laser and the second preheating laser.
According to one embodiment of the invention, the first preheating laser is arranged close to the cladding laser in the circumferential direction of the axle to be repaired;
wherein the first preheating laser emits spot laser;
the second preheating laser emits linear laser.
Specifically, this embodiment provides another embodiment of the preheating module, where the preheating laser close to the cladding laser preheats in a laser spot form, the laser preheating spot diameter is 4 to 6mm, and the distance between the preheating spot and the laser cladding spot is 1 to 4 mm.
The distance between the preheating laser spot and the cladding laser spot is too small, and the preheating laser enters a molten pool and cannot play a role in preheating the base material; the preheating laser distance is too large to melt the laser, the preheating basal body becomes cool, and the preheating effect can not be achieved.
Further, the preheating laser far away from the cladding laser is preheated in a laser line form, the laser line width is 8-12 mm, the preheating laser on the side can achieve the purpose of preheating the base material on one hand, and can achieve the annealing effect on the cladding metal on the other hand, and the residual stress generated by cladding metal shrinkage is reduced.
According to a second aspect of the invention, the laser cladding remanufacturing method for the railway vehicle axle comprises the following steps:
turning the surface of the axle to be repaired;
carrying out ultrasonic impact treatment on the surface of the axle to be repaired after turning treatment through an ultrasonic module;
and carrying out cladding treatment on the surface of the base material of the axle to be repaired after the turning treatment by using a cladding laser.
According to an embodiment of the present invention, the step of performing ultrasonic impact treatment on the surface of the axle to be repaired after turning by using the ultrasonic module specifically includes:
and carrying out ultrasonic impact treatment on the surface of the base material subjected to axle turning to be repaired at least twice through the ultrasonic module.
Specifically, the embodiment provides an implementation manner in which the ultrasonic module performs ultrasonic impact on the surface of the axle to be repaired after turning, and after at least two ultrasonic impacts, it can be ensured that a distortion layer of at least about 0.3mm can be formed on the surface of the axle to be repaired.
The distortion layer is expressed as compressive stress, and the existence of the distortion layer stress can eliminate residual tensile stress generated by solidification and shrinkage of cladding metal, so that the fatigue performance of remanufactured axles is improved.
According to an embodiment of the present invention, before performing the cladding process on the surface of the axle to be repaired after the turning process by using the cladding laser, the method specifically further includes:
and cleaning the surface of the base material of the axle to be repaired, which is subjected to the impact treatment of the ultrasonic module, by using a cleaning laser.
Particularly, this embodiment provides a treat that repair the axletree after turning through the implementation mode that substrate surface that ultrasonic module impact was handled washs, through washing the laser instrument to the surface of treating repairing after the ultrasonic impact washs the operation, has realized getting rid of influence laser cladding refabrication factor such as oxide, greasy dirt, dust.
In an application scene, the clamping mechanism is a lathe with a corresponding clamping structure, and the axle to be repaired is clamped on the lathe, and a manipulator is used for putting on the cleaning laser. When laser cleaning is used as a single process, the time interval between cleaning operation and cladding operation is not more than 4h, so that the surface of the axle is prevented from being polluted again; the laser cleaning process parameters are as follows: the laser cleaning power is 100 to 500W, the laser cleaning speed is 0.01 to 0.03m/s, and the cleaning width is 10 to 30 mm.
In an application scene, the clamping mechanism is a lathe with a corresponding clamping structure, and the axle to be repaired is clamped on the lathe, and the cleaning laser and the cladding laser are coupled and arranged on the same fixed structure together, so that an integrated operation mode of cleaning and cladding simultaneously is realized.
In one application scenario, the laser line width emitted by the cleaning laser is in the range of 10mm to 30mm and is adjustable. The laser cleaning process parameters are as follows: the laser cleaning power is 100 to 500W, the laser cleaning speed is 0.01 to 0.03m/s, and the cleaning width is 10 to 30 mm.
According to an embodiment of the present invention, before performing the cladding process on the surface of the axle to be repaired after the turning process by using the cladding laser, the method specifically further includes:
preheating the surface of the base material cleaned by the cleaning laser through the axle to be repaired by a preheating module;
the first preheating laser and the second preheating laser are oppositely arranged along the circumferential direction of the axle to be repaired, and simultaneously, the surface of the axle to be repaired is preheated;
and detecting the surface temperature of the axle to be repaired through a temperature sensor, and stopping preheating after the surface temperature of the axle to be repaired reaches a preset temperature.
Specifically, this embodiment provides one kind to treat the implementation mode that the surface after the repair axletree turned preheats, sets up first preheating laser and second preheating laser in the radial of treating the repair axletree relatively, and this kind of mode is symmetrical double preheating, can effectively avoid refabrication axletree to preheat the stress problem of inhomogeneous production through symmetrical double preheating.
Further, the surface to be repaired is heated using a laser as a heat source, and the temperature of the heated surface is measured using a temperature sensor (e.g., an infrared induction thermometer). And heating the position to be repaired of the axle to be repaired to 100-300 ℃, and further reducing the cooling speed of laser cladding. The precipitation of martensite phase in the damaged area of the base material is avoided.
It should be noted that, because the laser preheating range is small and the cooling speed is fast, the preheating laser and the cladding laser need to be integrated, so as to realize the integrated operation mode of simultaneous preheating and simultaneous cladding.
In one application scenario, semiconductor lasers are used as emission sources of the first preheating laser and the second preheating laser.
According to an embodiment of the present invention, the step of performing cladding processing on the surface of the axle to be repaired after turning processing by using a cladding laser specifically includes:
carrying out primary laser cladding and secondary laser cladding on the surface of the base material of the axle to be repaired cleaned by the cleaning laser through the cladding laser;
and the laser power of the first laser cladding is less than that of the second laser cladding, and the cladding time of the first laser cladding is less than that of the second laser cladding.
Specifically, the embodiment provides an implementation method for performing cladding processing on a turned axle surface to be repaired by using a cladding laser, and after the axle surface to be repaired is impacted by using an ultrasonic impact technology, a crushed layer of about 12 to 18 micrometers is generated on the impacted surface, and a large number of hole defects exist. In order to eliminate the hole defect of the broken layer, laser cladding is completed by two times. The remelting of the surface to be repaired of the axle is mainly completed by the first laser cladding, and the defect of a hole is eliminated; and completing supplement of missing materials of the axle by secondary laser cladding, and completing remanufacturing of the axle.
One or more technical solutions in the present invention have at least one of the following technical effects: according to the laser cladding remanufacturing device and the remanufacturing method for the axle of the railway vehicle, the ultrasonic impact technology is adopted to impact the surface of the base material of the axle to be repaired, and the distortion energy and the compressive stress are introduced into the surface of the base material in advance, so that the problems of the coarsening of the structure of the heat damage layer of the base material and the residual tensile stress in the laser cladding remanufacturing process are solved.
Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.
Drawings
In order to more clearly illustrate the technical solutions of the present invention or the prior art, the drawings needed for the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and those skilled in the art can also obtain other drawings according to the drawings without creative efforts.
FIG. 1 is one of the schematic assembly views of a laser cladding remanufacturing apparatus for a railway vehicle axle provided by the present invention;
fig. 2 is a second assembly relationship schematic diagram of the laser cladding remanufacturing device for the axle of the rail vehicle, which is provided by the invention;
fig. 3 is a schematic flow chart of a laser cladding remanufacturing method of a railway vehicle axle provided by the invention.
Reference numerals:
10. an axle to be repaired;
20. cladding a laser;
30. an ultrasonic module;
40. cleaning the laser;
50. a first pre-heating laser;
60. a second pre-heating laser;
70. a temperature sensor.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention.
In the description of the embodiments of the present invention, it should be noted that the terms "center", "longitudinal", "lateral", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience in describing the embodiments of the present invention and simplifying the description, but do not indicate or imply that the referred devices or elements must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the embodiments of the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.
Fig. 1 is one of the assembly relationship schematic diagrams of the laser cladding remanufacturing device for the railway vehicle axle provided by the invention. Fig. 1 shows the arrangement of the cladding laser 20, the cleaning laser 40, the first pre-heating laser 50 and the second pre-heating laser 60 with respect to the axle 10 to be repaired.
Fig. 2 is a second schematic assembly view of the laser cladding remanufacturing device for the railway vehicle axle provided by the invention. Fig. 2 further illustrates the arrangement relationship of the cladding laser 20, the ultrasonic module 30, the cleaning laser 40, the first preheating laser 50, the second preheating laser 60, and the temperature sensor 70 with respect to the axle 10 to be repaired.
Fig. 3 is a schematic flow chart of a laser cladding remanufacturing method of a railway vehicle axle provided by the invention. Fig. 3 shows a flow of the laser cladding remanufacturing method of the railway vehicle axle of the present invention.
The laser cladding technology is used for remanufacturing the scrapped axle of the railway vehicle, the cost can be saved by more than 50%, the steel waste is reduced by more than 70%, and the laser cladding technology is a green and advanced repairing technology. The laser cladding remanufactured axle can be divided into 4 areas, namely a cladding area, an interface layer, a substrate heat damage area and a substrate. Aiming at the problem of damage of a base material of a remanufactured axle of a railway vehicle through laser cladding, the invention develops a set of laser cladding remanufacturing pretreatment method for the axle of the railway vehicle, introduces distortion energy and compressive stress in advance at the position of a damaged area of the base material through an ultrasonic impact technology, and solves the problems of texture coarsening and residual tensile stress of the damaged area of the base material. In addition, the laser cladding cooling speed is reduced through preheating treatment, and the problem of precipitation of hard and brittle martensite phase in the heat damage area of the base material is solved.
Therefore, by implementing the laser cladding remanufacturing pretreatment method for the railway vehicle axle, the mechanical property of the laser cladding remanufactured axle is improved, and the service life of the remanufactured axle is prolonged.
Furthermore, the temperature of the damaged area of the substrate close to the interface layer is higher and exceeds the phase transition temperature. The bainite structure of the base material is transformed into an austenite structure under the action of the laser thermal field. After laser leaves, because the laser cladding cooling speed is higher, an austenite structure can not be converted into a bainite structure, but forms hard and brittle martensite, the hardness is improved, and the toughness and the fatigue performance of the axle are reduced.
The temperature of the position of the substrate damage layer close to the substrate is lower and does not exceed the phase transition temperature, so that the phase transition can not occur under the action of a laser thermal field, but the original bainite structure can grow up to form a coarsened bainite structure, and the performance of the axle is reduced.
In addition, the solidification shrinkage of the cladding area and the interface layer can also form residual tensile stress on a damaged layer of the base material, and the fatigue performance of the remanufactured axle is seriously influenced.
In summary, the presence of the martensite phase, coarse texture and residual stresses in the damaged areas of the substrate make them weak points for remanufactured axles, severely affecting the performance of the remanufactured axles.
In the description of the embodiments of the present invention, it should be noted that, unless explicitly stated or limited otherwise, the terms "connected" and "connected" are to be interpreted broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; may be directly connected or indirectly connected through an intermediate. Specific meanings of the above terms in the embodiments of the present invention can be understood in specific cases by those of ordinary skill in the art.
In embodiments of the invention, unless expressly stated or limited otherwise, the first feature "on" or "under" the second feature may be directly contacting the first and second features or indirectly contacting the first and second features through intervening media. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.
In some embodiments of the present invention, as shown in fig. 1 and 2, the present disclosure provides a laser cladding remanufacturing apparatus for a railway vehicle axle, comprising: the clamping mechanism, the cladding laser 20 and the ultrasonic module 30; the clamping mechanism is used for clamping the axle 10 to be repaired; the cladding laser 20 is arranged corresponding to the part to be repaired of the axle 10 to be repaired and is used for repairing the axle 10 to be repaired; the ultrasonic module 30 is disposed corresponding to a portion to be repaired of the axle 10 to be repaired, and is configured to impact a substrate surface of the axle 10 to be repaired, where at least a portion of the substrate surface is damaged by laser emitted by the cladding laser 20 during the laser cladding remanufacturing process.
In detail, the invention provides a laser cladding remanufacturing device of a railway vehicle axle, which is used for solving the defects that in the prior art, the surface of a base material is damaged in the cladding remanufacturing process of the base material by laser, the base material at the position near the surface to be repaired of the base material is coarsened in tissue, the performance of the remanufactured axle is seriously deteriorated, and the residual tensile stress is formed in the damaged area of the base material.
In some possible embodiments, the method further comprises: and the cleaning laser 40 is arranged close to the cladding laser 20 along the circumferential direction of the axle 10 to be repaired and used for cleaning the surface of the base material of the axle 10 to be repaired after being impacted by the ultrasonic module 30.
Specifically, the embodiment provides an implementation manner of a laser cladding remanufacturing device, and the cleaning laser 40 is arranged to clean the surface to be repaired after ultrasonic impact, so as to remove factors affecting laser cladding remanufacturing, such as oxides, oil stains, and dust.
In one application scenario, the clamping mechanism is a lathe with a corresponding clamping structure, and the axle 10 to be repaired is clamped on the lathe, and then the manipulator is used to put on the cleaning laser 40. When laser cleaning is used as a single process, the time interval between cleaning operation and cladding operation is not more than 4h, so that the surface of the axle is prevented from being polluted again; the laser cleaning process parameters are as follows: the laser cleaning power is 100 to 500W, the laser cleaning speed is 0.01 to 0.03m/s, and the cleaning width is 10 to 30 mm.
In an application scenario, the clamping mechanism is a lathe with a corresponding clamping structure, the axle 10 to be repaired is clamped on the lathe, and the cleaning laser 40 and the cladding laser 20 are coupled and arranged on the same fixed structure together, so that an integrated operation mode of cleaning and cladding is realized.
In one application scenario, the width of the laser line emitted by the cleaning laser 40 is in the range of 10mm to 30mm and is adjustable; the laser cleaning process parameters are as follows: the laser cleaning power is 100 to 500W, the laser cleaning speed is 0.01 to 0.03m/s, and the cleaning width is 10 to 30 mm.
In some possible embodiments, the method further comprises: and the preheating module is arranged corresponding to the part to be repaired of the axle 10 to be repaired and is used for preheating the axle 10 to be repaired.
Specifically, the embodiment provides another embodiment of a laser cladding remanufacturing device, and the preheating treatment is performed before the laser cladding of the axle 10 to be repaired, so that the cooling rate of the laser cladding can be reduced, and the problem of precipitation of hard and brittle martensite in the heat damaged area of the substrate is solved. By implementing the laser cladding remanufacturing pretreatment method, the mechanical property of the laser cladding remanufactured axle is improved, and the service life of the remanufactured axle is prolonged.
It should be noted that, due to the cooling shrinkage effect of the clad metal, tensile stress is formed in the damaged region of the base material, and the fatigue performance of the remanufactured axle is reduced. The above problem makes the damaged layer of the substrate become a weak area of the remanufactured axle, which seriously affects the safety of use of the remanufactured axle. Aiming at the problem of substrate damage caused by laser cladding remanufacturing, the preheating treatment is carried out before the laser cladding remanufacturing of the axle 10 to be repaired, so that the problems of coarsening of the structure, residual tensile stress and martensite transformation of a heat damaged layer of the substrate can be effectively solved, the mechanical performance of the laser cladding remanufacturing axle is improved, and the service life of the remanufacturing axle is prolonged.
In some possible embodiments, the pre-heat module comprises: a first pre-heat laser 50, a second pre-heat laser 60, and a temperature sensor 70; the first preheating laser 50 and the second preheating laser 60 are arranged opposite to each other in the radial direction of the repair axle; the temperature sensor 70 is provided corresponding to the portion to be repaired of the axle 10 to be repaired, and detects the temperature of the heat damaged area of the base material.
Specifically, the embodiment provides an implementation manner of a preheating module, wherein a first preheating laser 50 and a second preheating laser 60 are arranged in a radial direction of the axle 10 to be repaired, and this mode is symmetrical double preheating, so that the stress problem caused by nonuniform preheating of the remanufactured axle can be effectively avoided by symmetrical double preheating.
Further, the surface to be repaired is heated using a laser as a heat source, and the temperature of the heated surface is measured using a temperature sensor 70 (e.g., an infrared induction thermometer). And heating the position to be repaired of the axle 10 to be repaired to 100-300 ℃, and further reducing the cooling speed of laser cladding. The precipitation of martensite phase in the damaged area of the base material is avoided.
In one application scenario, the temperature sensor 70 includes a first sensor disposed in correspondence with the first preheat laser 50 and a second sensor disposed in correspondence with the second preheat laser 60.
It should be noted that, because the laser preheating range is small and the cooling speed is fast, the preheating laser and the cladding laser 20 need to be integrated, so as to realize an integrated operation mode of simultaneous preheating and simultaneous cladding.
In one application scenario, semiconductor lasers are used as the emission sources of first pre-heat laser 50 and second pre-heat laser 60.
In some possible embodiments, the first pre-heating laser 50 is disposed proximate to the cladding laser 20 in the circumferential direction of the axle 10 to be repaired; wherein the first preheating laser 50 emits a spot laser; the second pre-heating laser 60 emits linear laser light.
Specifically, this embodiment provides another embodiment of the preheating module, where the preheating laser close to the cladding laser preheats in a laser spot form, the laser preheating spot diameter is 4 to 6mm, and the distance between the preheating spot and the laser cladding spot is 1 to 4 mm.
The distance between the preheating laser spot and the cladding laser spot is too small, and the preheating laser enters a molten pool and cannot play a role in preheating the base material; the preheating laser distance is too large to melt the laser, the preheating basal body becomes cool, and the preheating effect can not be achieved.
Further, the preheating laser far away from the cladding laser is preheated in a laser line form, the laser line width is 8-12 mm, the preheating laser on the side can achieve the purpose of preheating the base material on one hand, and can achieve the annealing effect on the cladding metal on the other hand, and the residual stress generated by cladding metal shrinkage is reduced.
In some embodiments of the present invention, as shown in fig. 3, the present disclosure provides a laser cladding remanufacturing method of a rail vehicle axle, which has the above-mentioned laser cladding remanufacturing apparatus of a rail vehicle axle, the method including:
turning the surface of the axle 10 to be repaired;
performing ultrasonic impact treatment on the surface of the axle 10 to be repaired after turning treatment through the ultrasonic module 30;
and performing cladding treatment on the surface of the base material of the axle 10 to be repaired after the turning treatment by using a cladding laser 20.
In detail, the invention also provides a laser cladding remanufacturing method of the railway vehicle axle, which is used for solving the defects that in the prior art, the surface of the base material is damaged in the cladding remanufacturing process of the base material by laser, the base material at the position near the surface to be repaired of the base material is formed by coarsening the structure, the remanufacturing axle performance is seriously deteriorated, and the residual tensile stress is formed in the damaged area of the base material.
The method has the advantages that by implementing the laser cladding remanufacturing pretreatment method for the axle of the railway vehicle, the problems of precipitation of hard and brittle martensite phases, coarsening of the structure and residual tensile stress of the heat damaged layer of the base material are solved, the performance of the damaged layer of the base material is effectively improved, the mechanical performance of the laser cladding remanufactured axle is improved, and the service life of the remanufactured axle is prolonged.
In some possible embodiments, the step of turning the surface of the axle 10 to be repaired specifically includes: clamping an axle 10 to be repaired of the rail vehicle with the scratch exceeding the limit on a three-jaw chuck of a lathe, and removing the defect position by using the lathe by 0.1-0.3 mm according to the scratch condition on the basis of removing the defect completely. And after the defects are removed, flaw detection is carried out on the turned surface by using a magnetic powder flaw detection technology, so that the scratch is completely and completely removed. The surface roughness of the turned axle is not more than Ra6.4, and the turning process comprises the following steps: feeding amount: 0.1 to 0.2 mm/r; feeding speed: 0.1 to 0.2 mm/r; rotation speed: 400 to 600 r/min.
Specifically, if the scratch defect occurs at the wheel seat position of the axle, the whole wheel seat is removed by 0.1-0.3 mm, and if the scratch defect occurs at the wheel seat position, the whole size seat is removed by 0.1-0.3 mm.
In some possible embodiments, the step of performing the ultrasonic impact treatment on the surface of the axle 10 to be repaired after the turning treatment by the ultrasonic module 30 specifically includes:
the ultrasonic impact treatment is performed at least twice on the surface of the base material after turning the axle 10 to be repaired by the ultrasonic module 30.
Specifically, the embodiment provides an implementation manner in which the ultrasonic module 30 performs ultrasonic impact on the surface of the axle 10 to be repaired after turning, and after at least two ultrasonic impacts, a distortion layer of at least about 0.3mm can be formed on the surface of the axle 10 to be repaired.
The distortion layer is expressed as compressive stress, and the existence of the distortion layer stress can eliminate residual tensile stress generated by solidification shrinkage of cladding metal, so that the fatigue performance of a remanufactured axle is improved.
In an application scene, the processed axle is wiped clean by using cotton and linen dipped in absolute ethyl alcohol, and no oil stain or dust is required. And (3) carrying out ultrasonic impact on the axle 10 to be repaired, which is clamped on the lathe, by using an ultrasonic impact device lapped with a manipulator. Ultrasonic impact technology can introduce distortion energy on the surface of the material to be repaired. After two times of ultrasonic impact, a distortion layer with the thickness of about 0.3mm can be formed on the surface to be repaired, a distortion layer with the thickness of about 0.3-0.4 mm can be formed on the surface to be repaired after 3-5 times of ultrasonic impact, a distortion layer with the thickness of 0.4-0.5 mm can be formed on the surface to be repaired after 6-8 times of ultrasonic impact, the number of ultrasonic impact is increased, and the thickness of the distortion layer is not obviously increased. The stress of the distortion layer is tested by an X-ray method, and the result shows that the distortion layer is expressed as compressive stress, the residual tensile stress generated by solidification shrinkage of cladding metal can be eliminated by the existence of the distortion layer stress, and the fatigue performance of the remanufactured axle is improved. The structural state is observed, after ultrasonic treatment, the distorted layer structure is deformed to form higher distortion energy, and the distorted layer can generate a recrystallization phenomenon to form a fine recrystallized structural state by matching with a thermal field generated by laser cladding, so that the problem of coarsening of the substrate damaged layer structure is solved.
In addition, the surface layer of the axle is inevitably crushed by ultrasonic impact, the surface roughness is increased, and the influence of the ultrasonic impact on the surface layer crushing and the roughness of the axle is reduced through a specific impact parameter combination. Specifically, the small parameters are firstly used for impacting the surface to be repaired of the axle, so that the surface hardness and the impact resistance are improved, and the specific parameter ranges are as follows: the ultrasonic impact frequency is 20 to 28KHZ, the ultrasonic impact power is 100 to 200W, and the rotating speed of the axle is 500 to 900 r/min; and then, impacting the surface to be repaired of the axle by using the large parameters to improve the thickness of the distorted layer. The specific parameter ranges are as follows: the ultrasonic impact frequency is 20 to 28KHZ, the ultrasonic impact power is 300 to 500W, and the rotating speed of the axle is 400 to 600 r/min.
In some possible embodiments, before performing the cladding process on the surface of the axle 10 to be repaired after the turning process by the cladding laser 20, specifically, the method further includes:
the surface of the substrate on which the axle 10 to be repaired is subjected to the impact treatment by the ultrasonic module 30 is cleaned by the cleaning laser 40.
Specifically, the embodiment provides an implementation mode for cleaning the surface of the base material after turning the axle 10 to be repaired, and the cleaning operation is performed on the surface to be repaired after ultrasonic impact by the cleaning laser 40, so that the factors affecting laser cladding remanufacturing, such as oxides, oil stains, dust, and the like, are removed.
In one application scenario, the clamping mechanism is a lathe with a corresponding clamping structure, and the axle 10 to be repaired is clamped on the lathe, and then the manipulator is used for lapping the cleaning laser 40. When laser cleaning is used as a separate process, the interval time between cleaning operation and cladding operation does not exceed 4h, so that the surface of the axle is prevented from being polluted again; the laser cleaning process parameters are as follows: the laser cleaning power is 100 to 500W, the laser cleaning speed is 0.01 to 0.03m/s, and the cleaning width is 10 to 30 mm.
In an application scenario, the clamping mechanism is a lathe with a corresponding clamping structure, the axle 10 to be repaired is clamped on the lathe, and the cleaning laser 40 and the cladding laser 20 are coupled and arranged on the same fixed structure together, so that an integrated operation mode of cleaning and cladding is realized.
In one application scenario, the width of the laser line emitted by the cleaning laser 40 is in the range of 10mm to 30mm and is adjustable; the laser cleaning process parameters are as follows: the laser cleaning power is 100 to 500W, the laser cleaning speed is 0.01 to 0.03m/s, and the cleaning width is 10 to 30 mm.
In some possible embodiments, before performing the cladding process on the surface of the axle 10 to be repaired after the turning process by the cladding laser 20, specifically, the method further includes:
preheating the surface of the base material cleaned by the cleaning laser 40 on the axle 10 to be repaired by a preheating module;
the first preheating laser 50 and the second preheating laser 60 are oppositely arranged along the circumferential direction of the axle 10 to be repaired, and simultaneously, the surface of the axle 10 to be repaired is preheated;
the surface temperature of the axle 10 to be repaired is detected by the temperature sensor 70, and the preheating is stopped after the surface temperature of the axle 10 to be repaired reaches a preset temperature.
Specifically, the embodiment provides an implementation manner for preheating the turned surface of the axle 10 to be repaired, the first preheating laser 50 and the second preheating laser 60 are arranged in the radial direction of the axle 10 to be repaired in a manner of symmetrical double preheating, and the stress problem caused by uneven preheating of the remanufactured axle can be effectively avoided through symmetrical double preheating.
Further, the surface to be repaired is heated using a laser as a heat source, and the temperature of the heated surface is measured using a temperature sensor 70 (e.g., an infrared induction thermometer). And heating the position to be repaired of the axle 10 to be repaired to 100-300 ℃, and further reducing the cooling speed of laser cladding. The precipitation of martensite phase in the damaged area of the base material is avoided.
It should be noted that, because the laser preheating range is small and the cooling speed is fast, the preheating laser and the cladding laser 20 need to be integrated, so as to realize an integrated operation mode of simultaneous preheating and simultaneous cladding.
In one application scenario, semiconductor lasers are used as the emission sources of first pre-heat laser 50 and second pre-heat laser 60.
In some possible embodiments, the step of performing the cladding process on the surface of the axle 10 to be repaired after the turning process by the cladding laser 20 specifically includes:
carrying out primary laser cladding and secondary laser cladding on the surface of the base material of the axle 10 to be repaired, which is cleaned by the cleaning laser 40, through the cladding laser 20;
and the laser power of the first laser cladding is less than that of the second laser cladding, and the cladding time of the first laser cladding is less than that of the second laser cladding.
Specifically, the embodiment provides an implementation manner of performing cladding processing on the surface of the axle 10 to be repaired after turning processing by using a cladding laser 20, and after the surface to be repaired is impacted by using an ultrasonic impact technology, a crushed layer of about 12 to 18 micrometers is generated on the impacted surface, and a large number of hole defects exist. In order to eliminate the hole defect of the broken layer, laser cladding is completed by two times. The remelting of the surface of the axle to be repaired is mainly completed by the first laser cladding, and the defect of a hole is eliminated; and completing the supplement of the missing materials of the axle by the second laser cladding, and completing the remanufacturing of the axle.
In an application scene, the first laser cladding directly contacts the axle base material, and in order to avoid an overlarge heat input and a large heat affected zone, small parameters are required for cladding, and the specific process parameters are as follows: laser type: a semiconductor laser; the laser power is 1 to 1.5 kw; the diameter of the light spot is 3 mm; scanning rate: 20 to 30 mm/s; lapping amount: 50 percent; distance of nozzle from workpiece: 10 to 15 mm; powder feeding mode: and (4) coaxially feeding powder.
In another application scenario, appropriate process parameters need to be formulated according to the selected filling material for repairing the main axle damage layer by secondary laser cladding, and the specific steps are as follows: the cladding material is heterogeneous to the axle 10 to be repaired.
When the iron-based material is selected as the filling material, the laser cladding process parameters are as follows: laser type: a semiconductor laser; the laser power is 2 to 2.5 kw; the diameter of the light spot is 3 mm; scanning rate: 8 to 10 mm/s; lapping amount: 50 percent; distance of nozzle from workpiece: 10 to 15 mm; powder feeding mode: coaxially feeding powder;
when a nickel-based material is selected as a filling material, the laser cladding process parameters are as follows: laser type: a semiconductor laser; the laser power is 2 to 2.25 kw; the diameter of the light spot is 3 mm; scanning rate: 8 to 10 mm/s; lapping amount: 50 percent; distance of nozzle from workpiece: 10 to 15 mm; powder feeding mode: and (4) coaxially feeding powder.
In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of an embodiment of the invention. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.
Finally, it should be noted that: the above embodiments are merely illustrative of the present invention and are not to be construed as limiting the invention. Although the present invention has been described in detail with reference to the embodiments, it should be understood by those skilled in the art that various combinations, modifications or equivalents may be made to the technical solution of the present invention without departing from the spirit and scope of the technical solution of the present invention, and the technical solution of the present invention is covered by the claims of the present invention.
Claims (3)
1. The utility model provides an axletree laser cladding refabrication method based on laser cladding refabrication device which characterized in that, the device includes: the device comprises a clamping mechanism, a cladding laser, an ultrasonic module and a preheating module;
the clamping mechanism is used for clamping the axle to be repaired;
the cladding laser is arranged corresponding to the part to be repaired of the axle to be repaired and is used for repairing the axle to be repaired;
the ultrasonic module is arranged corresponding to the part to be repaired of the axle to be repaired and is used for impacting the surface of the base material of the axle to be repaired;
the preheating module is arranged corresponding to the part to be repaired of the axle to be repaired and is used for preheating the axle to be repaired;
wherein the preheating module comprises: a first pre-heating laser and a second pre-heating laser; the first preheating laser and the second preheating laser are arranged opposite to each other in the radial direction of the repair axle;
the method comprises the following steps:
turning the surface of the axle to be repaired;
performing ultrasonic impact treatment on the surface of the base material after turning the axle to be repaired at least twice through the ultrasonic module, and forming a distortion layer on the surface of the base material;
cleaning the surface of the base material, which is subjected to the impact treatment by the ultrasonic module, of the axle to be repaired by a cleaning laser;
preheating the surface of the base material cleaned by the cleaning laser through the axle to be repaired by a preheating module; the first preheating laser and the second preheating laser are oppositely arranged along the circumferential direction of the axle to be repaired, and simultaneously, the surface of the axle to be repaired is preheated;
detecting the surface temperature of the axle to be repaired through a temperature sensor, and stopping preheating after the surface temperature of the axle to be repaired reaches a preset temperature;
carrying out primary laser cladding and secondary laser cladding on the surface of the base material of the axle to be repaired cleaned by the cleaning laser through the cladding laser; and the laser power of the first laser cladding is smaller than that of the second laser cladding, and the cladding time of the first laser cladding is shorter than that of the second laser cladding.
2. The axle laser cladding remanufacturing method based on the laser cladding remanufacturing device is characterized by further comprising the following steps of: and the cleaning laser is arranged close to the cladding laser along the circumferential direction of the axle to be repaired and is used for cleaning the surface of the base material of the axle to be repaired after being impacted by the ultrasonic module.
3. The laser cladding remanufacturing method for the axle based on the laser cladding remanufacturing device according to claim 1, wherein the first preheating laser is arranged close to the cladding laser in the circumferential direction of the axle to be repaired;
wherein the first preheating laser emits spot laser;
the second preheating laser emits linear laser.
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| CN107723700A (en) * | 2017-08-23 | 2018-02-23 | 韩传怀 | A kind of restorative procedure to run out bearing |
| CN107675167A (en) * | 2017-09-04 | 2018-02-09 | 中国航发北京航空材料研究院 | A kind of superhigh intensity steel member ultrasonic impact auxiliary laser cladding restorative procedure |
| CN109385631A (en) * | 2018-12-10 | 2019-02-26 | 山东泰利先进制造研究院有限公司 | A kind of laser melting coating complex repairation manufacturing method and its application |
| CN111910182A (en) * | 2020-07-02 | 2020-11-10 | 南京派纳克激光科技有限公司 | Repair powder for laser cladding of axle and repair method thereof |
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