A method and apparatus for heat-treated steel rails based on ultrasonic deep rolling

Abstract

This invention provides a method and apparatus for auxiliary strengthening of heat-treated steel rails based on ultrasonic deep rolling, relating to the field of rail transit equipment maintenance technology. The method includes: acquiring the hardened layer property parameters and residual stress parameters of the heat-treated steel rail; calculating the static load, amplitude, overlap rate, and rolling cycles required for ultrasonic deep rolling based on the hardened layer property parameters and residual stress parameters; acquiring the wheel-rail contact condition of the heat-treated steel rail head and dividing the rail head into multiple different processing areas according to the wheel-rail contact condition; performing ultrasonic deep rolling processing in different processing areas with different lateral step distances using an ultrasonic deep rolling device with configured parameters; and performing performance testing on the ultrasonically deep-rolled steel rail to confirm that the hardness gradient and residual stress distribution after ultrasonic deep rolling treatment meet preset indicators. This invention addresses the technical problem of existing technologies failing to maintain high wear resistance while simultaneously achieving excellent fatigue resistance.

Description

Technical Field

[0001] This invention relates to the field of rail transit equipment maintenance technology, and more specifically, to a method and device for auxiliary strengthening of heat-treated rails based on ultrasonic deep rolling. Background Technology

[0002] Existing methods for extending the service life of railway rails mainly include rail profile grinding and heat treatment processes such as quenching and laser cladding. Rail grinding repairs the profile by cutting material, but its effect on service life is limited and it requires frequent maintenance, making it uneconomical. Heat treatment processes such as quenching and cladding can significantly improve the wear resistance of rails; however, they create a large hardness gradient and uneven residual stress distribution between the hardened layer and the base material. This leads to stress concentration at the edge of the hardened layer under wheel-rail loads, causing severe fatigue cracks and resulting in a decrease in rail fatigue life instead of an increase. Therefore, existing technologies struggle to maintain high wear resistance while simultaneously achieving excellent fatigue resistance, thus limiting further improvements in the overall service life of heat-treated rails. Summary of the Invention

[0003] The purpose of this invention is to provide a method and apparatus for assisting in the strengthening of heat-treated rails based on ultrasonic deep rolling, so as to improve the above-mentioned problems. To achieve the above objective, the technical solution adopted by this invention is as follows:

[0004] In a first aspect, this application provides a heat-treated rail-assisted strengthening method based on ultrasonic deep rolling, comprising:

[0005] Obtain the hardened layer property parameters and residual stress parameters of the heat-treated rail;

[0006] Based on the hardened layer property parameters and residual stress parameters, the static load, amplitude, overlap rate and number of rolling cycles required for ultrasonic deep rolling are calculated.

[0007] The wheel-rail contact condition of the heat-treated rail head is obtained, and the heat-treated rail head is divided into multiple different processing areas based on the wheel-rail contact condition.

[0008] The parameters of the ultrasonic deep rolling equipment are configured according to static load, amplitude, overlap rate and rolling times. After the parameters are configured, the ultrasonic deep rolling equipment performs ultrasonic deep rolling processing in different processing areas with different lateral step distances.

[0009] The performance of the rails after ultrasonic deep rolling was tested to confirm that the hardness gradient and residual stress distribution after ultrasonic deep rolling met the preset indicators.

[0010] Secondly, this application also provides an auxiliary strengthening device for heat-treated rails based on ultrasonic deep rolling, comprising:

[0011] The parameter acquisition module is used to acquire the hardened layer property parameters and residual stress parameters of the heat-treated rail;

[0012] The parameter calculation module is used to calculate the static load, amplitude, overlap rate, and number of rolling cycles required for ultrasonic deep rolling based on the hardened layer property parameters and residual stress parameters.

[0013] The region division module is used to obtain the wheel-rail contact condition of the heat-treated rail head and divide the heat-treated rail head into multiple different processing regions based on the wheel-rail contact condition.

[0014] The processing control module is used to configure the parameters of the ultrasonic deep rolling equipment according to the static load, amplitude, overlap rate and rolling times. After the control parameters are configured, the ultrasonic deep rolling equipment performs ultrasonic deep rolling processing in different processing areas with different lateral step distances.

[0015] The performance testing module is used to test the performance of the rails after ultrasonic deep rolling to confirm that the hardness gradient and residual stress distribution after ultrasonic deep rolling treatment meet the preset indicators.

[0016] Thirdly, this application also provides an auxiliary strengthening device for heat-treated rails based on ultrasonic deep rolling, comprising:

[0017] Memory, used to store computer programs;

[0018] A processor is used to implement the steps of the ultrasonic deep rolling-based heat treatment rail-assisted strengthening method when executing the computer program.

[0019] Fourthly, this application also provides a readable storage medium storing a computer program that, when executed by a processor, implements the steps of the above-described heat-treated rail-assisted strengthening method based on ultrasonic deep rolling.

[0020] The beneficial effects of this invention are as follows:

[0021] This invention, by introducing ultrasonic deep rolling assisted processing after heat treatment, significantly reduces the hardness gradient between the hardened layer and the substrate through substrate grain refinement and hardness enhancement, thus avoiding edge stress concentration. Furthermore, it achieves residual stress redistribution, introducing a uniform residual compressive stress field on the rail surface, effectively suppressing the initiation and propagation of fatigue cracks. Therefore, this invention maintains the high wear resistance of heat-treated rails while simultaneously and significantly improving their fatigue life, achieving a synergistic increase in rail wear life and fatigue life. Ultimately, it significantly extends the overall service life of the rail and reduces maintenance costs throughout its entire life cycle.

[0022] Other features and advantages of the invention will be set forth in the following description, and will be apparent in part from the description, or may be learned by practicing embodiments of the invention. The objects and other advantages of the invention may be realized and obtained by means of the structures particularly pointed out in the written description, claims, and drawings. Attached Figure Description

[0023] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 This is a schematic diagram of the process of the heat treatment-assisted strengthening method for steel rails based on ultrasonic deep rolling as described in the embodiments of the present invention;

[0025] Figure 2 This is a top view of the heat-treated steel rail described in an embodiment of the present invention;

[0026] Figure 3 This is a hardness curve distribution diagram of the heat-treated steel rail described in this embodiment of the invention;

[0027] Figure 4 This is a residual stress distribution diagram of the heat-treated steel rail described in this embodiment of the invention;

[0028] Figure 5 This is a zoning diagram of the processing area of ​​the heat-treated steel rail described in this embodiment of the invention;

[0029] Figure 6 This is a hardness curve distribution diagram of railway rail heat-treated by ultrasonic deep rolling as described in an embodiment of the present invention.

[0030] Figure 7 This is a residual stress distribution diagram of railway rail heat-treated by ultrasonic deep rolling as described in an embodiment of the present invention.

[0031] Figure 8 This is a graph showing the relationship between rail wear life and fatigue life as described in an embodiment of the present invention.

[0032] Figure 9 This is a schematic diagram of the auxiliary strengthening device for heat-treated steel rails based on ultrasonic deep rolling as described in an embodiment of the present invention;

[0033] Figure 10 This is a schematic diagram of the structure of the heat-treated rail auxiliary strengthening device based on ultrasonic deep rolling as described in an embodiment of the present invention.

[0034] Marked in the image:

[0035] 800. Auxiliary strengthening equipment for heat-treated steel rails based on ultrasonic deep rolling; 801. Processor; 802. Memory; 803. Multimedia component; 804. I / O interface; 805. Communication component. Detailed Implementation

[0036] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0037] It should be noted that similar reference numerals and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. Furthermore, in the description of this invention, terms such as "first," "second," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0038] Example 1:

[0039] This embodiment provides a heat-treated rail-assisted strengthening method based on ultrasonic deep rolling.

[0040] See Figure 1 , Figure 2 The figure shows that this method includes:

[0041] S1. Obtain the hardened layer property parameters and residual stress parameters of the heat-treated rail;

[0042] Specifically, step S1 includes:

[0043] S11. Within the wheel-rail contact area on the rail surface, a metallographic sample is prepared by cutting along the wheel-rail contact centerline. In this embodiment, a wire cutting machine is used to cut a metallographic sample with a depth of 3 mm along the rail depth direction at the wheel-rail contact centerline on the heat-treated rail surface.

[0044] S12. Perform a hardness test on the cross-section of the sample and plot a hardness distribution curve based on the test results. In this embodiment, a microhardness tester is used to perform the hardness test on the cross-section of the sample. During the test, starting from the surface of the hardened layer, the measurement is performed vertically towards the substrate, and the center-to-center distance between two adjacent indentations should not exceed 100 μm. Record the positions of all measurement points and the corresponding Vickers hardness values ​​HV0.5, and plot the hardness distribution curve from the surface of the rail to its core accordingly. Figure 3 As shown.

[0045] S13. Determine the hardened layer depth based on the hardness distribution curve. Hardness of the hardened layer and hardness gradient , thus obtaining the hardened layer property parameters;

[0046] S14. Using an X-ray diffraction stress analyzer, measure the residual stress of the hardened layer on the cross-section of the sample. and residual stress of substrate The residual stress parameters are obtained, and a residual stress distribution diagram is drawn based on the residual stress parameters, such as... Figure 4 As shown. Generally speaking, the distribution of hardness and residual stress, from the center of the hardened layer to the rail substrate, is similar along the depth direction and along the surface direction.

[0047] Based on the above embodiments, this method further includes:

[0048] S2. Based on the hardened layer property parameters and residual stress parameters, the static load, amplitude, overlap rate and number of rolling cycles required for ultrasonic deep rolling are calculated;

[0049] Specifically, step S2 includes:

[0050] S21. Based on the hardened layer depth, the residual stress of the hardened layer, and the residual stress of the substrate, the static load required for ultrasonic deep rolling is calculated. Specifically, the static load The calculation method is as follows:

[0051] ;

[0052] S22. Based on the static load, hardened layer depth, and residual stress in the hardened layer, calculate the amplitude value required for ultrasonic deep rolling. Specifically, the amplitude value The calculation method is as follows:

[0053] ;

[0054] S23. Calculate the overlap rate of the ultrasonic deep rolling path based on the percentages of residual stress in the substrate and residual stress in the hardened layer. Specifically, the overlap rate The calculation method is as follows:

[0055] ;

[0056] S24. Calculate the required number of rolling passes based on the hardness and hardness gradient of the hardened layer. Specifically, the number of rolling cycles The calculation method is as follows:

[0057] ;

[0058] In the formula, This is the floor symbol.

[0059] Based on the above embodiments, this method further includes:

[0060] S3. Obtain the wheel-rail contact condition of the heat-treated rail head, and divide the heat-treated rail head into multiple different processing areas based on the wheel-rail contact condition, such as... Figure 5 As shown;

[0061] Specifically, step S3 includes:

[0062] S31. Obtain the distribution range of the wheel-rail contact light band or wheel-rail contact spot on the surface of the heat-treated rail head;

[0063] Specifically, the visible light band formed by wheel friction on the rail tread can be directly obtained through on-site inspection or image acquisition, and its total width L along the rail transverse direction and its center position on the rail head can be obtained.

[0064] Optionally, based on the known wheel tread profile and rail head profile, the theoretical shape and distribution range of the wheel-rail contact patch are simulated through geometric and mechanical calculations, and its total width L along the rail transverse direction and its center position on the rail head are obtained.

[0065] S32. Designate 80% of the central area of ​​the wheel-rail contact light strip or wheel-rail contact spot as the central processing area;

[0066] Specifically, taking the centerline of the wheel-rail contact distribution area as a reference, a width of 0.4L is taken on both sides. Therefore, the total width of the central processing area is... The calculation formula is:

[0067] ;

[0068] The central machining area is the core area where wheel-rail contact is most frequent and loads are most concentrated, therefore it requires the most intensive ultrasonic deep rolling machining.

[0069] S33. Designate 10% of the area on each side of the wheel-rail contact light strip or wheel-rail contact spot as a transition processing zone;

[0070] Specifically, on each side adjacent to the central processing area, a 0.1L wide area is designated as a transition processing area. Therefore, the width of the transition processing area on each side... The calculation formula is:

[0071] ;

[0072] The transition processing zone is a transitional area where the contact stress changes from strong to weak. It is a sensitive area for crack initiation and requires moderate-intensity processing to achieve a smooth performance transition.

[0073] S34. The area on the rail head surface that is not affected by wheel-rail contact is designated as the edge processing area.

[0074] Specifically, the area outside the transition processing zone, extending to the side of the rail head, is defined as the edge processing zone. Its width... The calculation formula is:

[0075] ;

[0076] In the formula, This indicates the total width of the rail head.

[0077] Since the edge processing zone is largely unaffected by wheel-rail contact loads and is primarily used to achieve complete coverage and geometrically smooth connection of the processing area, the edge processing zone employs the sparsest processing parameters.

[0078] Based on the above quantitative division, a gradient partitioning processing strategy based on wheel-rail contact state was established, from high-load area to no-load area, laying the foundation for the application of subsequent differentiated processes.

[0079] Based on the above embodiments, this method further includes:

[0080] S4. Configure the parameters of the ultrasonic deep rolling equipment according to the static load, amplitude, overlap rate and rolling times. After the parameters are configured, the ultrasonic deep rolling equipment performs ultrasonic deep rolling processing in different processing areas with different lateral step distances.

[0081] Specifically, step S4 includes:

[0082] S41. Control the ultrasonic deep rolling device to move in the central processing area at a first preset lateral step distance. Perform ultrasonic deep rolling, the The range of values ​​is ;

[0083] S42. Control the ultrasonic deep rolling device to move at a second preset lateral step distance in the transition processing zone. Perform ultrasonic deep rolling, the The range of values ​​is ;

[0084] S43. Control the ultrasonic deep rolling device to move at a third preset lateral step distance in the edge processing area. Perform ultrasonic deep rolling, the The range of values ​​is ;

[0085] Preferably, during the entire processing, the processing path adopts a "continuous path with equal contact force" according to the curvature change of the rail head. The rolling head is controlled by a CNC device to move at a constant speed along the rolling direction, and a unidirectional feed + reverse idle stroke is adopted to avoid stress concentration caused by repeated indentation.

[0086] Preferably, to avoid localized temperature rise during ultrasonic excitation, which could affect the tempering stability of the surface martensitic layer, and to reduce frictional damage between the roller and the rail, the following cooling and lubrication methods are used during processing: the cooling medium is an emulsion or low-viscosity mineral oil with a flow rate of 0.5–2 L / min; the coolant is directed through nozzles to the contact area between the roller and the rail head, forming a continuous cooling film; the cooling system is equipped with an online temperature sensor, which automatically compensates for the flow rate when the surface temperature exceeds 60–80 ℃; at the same time, lubrication can reduce rolling pressure fluctuations, reduce roller wear, and ensure consistent rolling contact.

[0087] By precisely controlling the above parameters and paths, a uniform residual compressive stress field is ensured to be formed on the rail head surface.

[0088] Furthermore, step S4 also includes a processing speed control step:

[0089] S44. In the substrate area, control the ultrasonic deep rolling device at a first processing speed. Processing is performed, preferably at the first processing speed. The value range is 1.0-1.5 mm / s;

[0090] S45. In the hardened layer, control the ultrasonic deep rolling device to smoothly increase to the second processing speed. During the processing, the ultrasonic deep rolling equipment sequentially goes through at least five speed control stages during the speed increase process.

[0091] Specifically, the second processing speed The calculation formula is:

[0092] ;

[0093] Specifically, in the boundary transition region between the hardened layer and the substrate, the feed speed of the ultrasonic deep rolling equipment is controlled to increase sequentially along the processing direction, undergoing a gradual acceleration process from the processing speed of the hardened layer to the processing speed of the substrate; the gradual acceleration process includes at least five incremental speed control stages, namely... , , , , , This results in a gradual increase in growth rate.

[0094] In this embodiment, the ultrasonic deep rolling device includes: an ultrasonic excitation module, a static load loading module, a roller assembly, a motion control module, and a control system.

[0095] The ultrasonic excitation module includes a piezoelectric ultrasonic transducer, an amplitude transformer, and a roller connection end. The operating frequency needs to meet the range of 0-40 kHz. The amplitude is adjusted by the drive power module and can be controlled in a closed loop by the amplitude sensor.

[0096] The static load loading module uses a servo motor-driven hydraulic loading unit, and the loading range needs to meet 0-3000 N. The loading force is collected in real time by a force sensor and fed back to the control system to realize static load closed-loop control.

[0097] The roller assembly includes a carbide roller coupled to the ultrasonic transducer. The roller diameter is 3-20 mm. It is supported by double-end bearings and needs to maintain a constant contact angle with the rail head surface according to the track curvature and the top profile of the rail.

[0098] The motion control module includes a CNC feed device, which can reciprocate at a speed of 0.1 to 2 mm / s in the rolling direction of the rail head, thereby achieving the set number of rolling cycles.

[0099] The control system uses a PLC or industrial computer, which can automatically calculate and adjust various parameters based on the static load, amplitude, and number of rolling cycles input by the user, thereby achieving automation and repeatability of the processing.

[0100] This embodiment effectively solves the problem of mismatched processing parameters between the hardened layer and the substrate due to differences in material properties. By gradually adjusting the speed, it ensures the consistency of processing quality in the transition area and avoids surface quality defects that may be caused by sudden speed changes.

[0101] Based on the above embodiments, this method further includes:

[0102] S5. Perform performance testing on the ultrasonically deep-rolled rail to confirm that the hardness gradient and residual stress distribution after ultrasonic deep-rolling meet the preset indicators; preferably, the preset indicators for the hardness gradient and residual stress distribution are respectively less than and less than ;

[0103] Specifically, step S5 includes:

[0104] S51. Resample and prepare test specimens from the ultrasonically deep-rolled rail. Perform hardness testing on the cross-section of the specimen using a microhardness tester, and plot a new hardness distribution curve, as shown below. Figure 6 As shown;

[0105] The measured hardness gradient can be obtained from the hardness curve distribution diagram. Because the measured hardness gradient is less than the preset index Therefore, the hardness gradient reaches the preset target.

[0106] In this embodiment, the grain size of the substrate is refined after ultrasonic rolling, and the hardness is increased by approximately [amount missing]. The hardened layer is refined during the heat treatment phase transformation process, while the grain size and hardness remain essentially unchanged. Therefore, it effectively reduces stress concentration at the edges of the hardened layer under wheel-rail rolling contact loads.

[0107] S52. Using an X-ray diffraction stress analyzer, measure the residual stress values ​​at various points in the wheel-rail contact center region on the rail surface. ,in, Indicates the first Measure at several points to plot the residual stress distribution, such as Figure 7 As shown.

[0108] Based on the residual stress values ​​at each point Calculate the average residual stress and residual stress sample standard deviation :

[0109] ;

[0110] In the formula, n is the total number of measurement points, and n≥5.

[0111] Based on the average residual stress and residual stress sample standard deviation Calculate the coefficient of variation :

[0112] ;

[0113] In this embodiment Much smaller than the preset target Therefore, it can be concluded that the residual stress distribution has reached the preset target.

[0114] In this embodiment, since the hardness gradient and residual stress distribution simultaneously meet their respective qualification standards, the performance of the rail after ultrasonic deep rolling is up to standard.

[0115] It should be noted that if any indicator fails to meet the preset requirements, the process parameters need to be adjusted and the process reprocessed.

[0116] This embodiment involves ultrasonic deep rolling of the heat-treated rail. This refines the grain structure of the substrate, reducing the large hardness gradient at the boundaries. Furthermore, it redistributes the residual stress in the hardened layer and the substrate, introducing a uniform residual compressive stress field onto the rail surface, thereby improving the rail's fatigue life. Figure 8 As shown, the ultrasonic deep rolling-assisted strengthening method provided in this embodiment optimizes the performance of heat-treated rails from a state that focuses on improving wear resistance but has poor fatigue life (such as M3) to a state that has both good wear life and fatigue life (such as M2), thereby comprehensively extending the overall service life of the rails.

[0117] Example 2:

[0118] like Figure 9 As shown, this embodiment provides an auxiliary strengthening device for heat-treated steel rails based on ultrasonic deep rolling. The device includes:

[0119] The parameter acquisition module is used to acquire the hardened layer property parameters and residual stress parameters of the heat-treated rail;

[0120] The parameter calculation module is used to calculate the static load, amplitude, overlap rate, and number of rolling cycles required for ultrasonic deep rolling based on the hardened layer property parameters and residual stress parameters.

[0121] The region division module is used to obtain the wheel-rail contact condition of the heat-treated rail head and divide the heat-treated rail head into multiple different processing regions based on the wheel-rail contact condition.

[0122] The processing control module is used to configure the parameters of the ultrasonic deep rolling equipment according to the static load, amplitude, overlap rate and rolling times. After the control parameters are configured, the ultrasonic deep rolling equipment performs ultrasonic deep rolling processing in different processing areas with different lateral step distances.

[0123] The performance testing module is used to test the performance of the rails after ultrasonic deep rolling to confirm that the hardness gradient and residual stress distribution after ultrasonic deep rolling treatment meet the preset indicators.

[0124] Based on the above embodiments, the parameter acquisition module includes:

[0125] The sampling unit is used to cut and prepare samples along the center line of the wheel-rail contact within the wheel-rail contact area on the rail surface.

[0126] The hardness testing unit is used to perform hardness testing on the cross-section of the sample and to plot a hardness distribution curve based on the hardness test results.

[0127] The attribute parameter determination unit is used to determine the hardened layer depth, hardened layer hardness and hardness gradient based on the hardness distribution curve, and to obtain the hardened layer attribute parameters.

[0128] The stress parameter measurement unit is used to measure the residual stress of the hardened layer and the residual stress of the substrate on the cross-section of the sample using an X-ray diffraction stress analyzer, so as to obtain the residual stress parameters.

[0129] Based on the above embodiments, the parameter calculation module includes:

[0130] The static load calculation unit is used to calculate the static load required for ultrasonic deep rolling based on the hardened layer depth, the residual stress of the hardened layer and the residual stress of the substrate.

[0131] An amplitude calculation unit is used to calculate the amplitude value required for ultrasonic deep rolling based on the static load, hardened layer depth, and residual stress in the hardened layer.

[0132] The overlap rate calculation unit is used to calculate the overlap rate of the ultrasonic deep rolling path based on the percentage of residual stress in the substrate and residual stress in the hardened layer.

[0133] The rolling cycle calculation unit is used to calculate the required number of rolling cycles based on the hardness and hardness gradient of the hardened layer.

[0134] Based on the above embodiments, the region division module includes:

[0135] The contact range acquisition unit is used to acquire the distribution range of the wheel-rail contact light band or wheel-rail contact spot on the surface of the heat-treated rail head.

[0136] The central area division unit is used to designate 80% of the central area of ​​the wheel-rail contact light strip or wheel-rail contact spot as the central processing area.

[0137] The transition zone division unit is used to designate 10% of the area on each side of the wheel-rail contact light strip or wheel-rail contact spot as a transition processing zone.

[0138] An edge area division unit is used to designate the area on the rail head surface that is not affected by wheel-rail contact as an edge processing area.

[0139] Based on the above embodiments, the processing control module includes:

[0140] The central processing unit is used to control the ultrasonic deep rolling equipment to perform ultrasonic deep rolling in the central processing area with a first preset lateral step distance.

[0141] The transition zone processing unit is used to control the ultrasonic deep rolling equipment to perform ultrasonic deep rolling in the transition processing zone with a second preset lateral step distance.

[0142] An edge processing unit is used to control the ultrasonic deep rolling equipment to perform ultrasonic deep rolling in the edge processing area with a third preset lateral step distance.

[0143] Based on the above embodiments, the processing control module further includes:

[0144] A substrate speed control unit is used to control the ultrasonic deep rolling equipment to process at a first processing speed in the substrate area;

[0145] The hardened layer speed control unit is used to control the ultrasonic deep rolling equipment to smoothly increase to a second processing speed during the hardened layer processing. The ultrasonic deep rolling equipment passes through at least five speed control stages in sequence during the speed increase process.

[0146] It should be noted that the specific manner in which each module performs its operation in the apparatus described in the above embodiments has been described in detail in the embodiments of the method, and will not be elaborated here.

[0147] Example 3:

[0148] Corresponding to the above method embodiments, this embodiment also provides an auxiliary strengthening device for heat-treated rails based on ultrasonic deep rolling. The auxiliary strengthening device for heat-treated rails based on ultrasonic deep rolling described below and the auxiliary strengthening method for heat-treated rails based on ultrasonic deep rolling described above can be referred to in correspondence.

[0149] Figure 10 This is a block diagram illustrating an auxiliary strengthening device 800 for heat-treated steel rails based on ultrasonic deep rolling, according to an exemplary embodiment. Figure 10 As shown, the ultrasonic deep rolling-based heat treatment rail auxiliary strengthening device 800 may include: a processor 801 and a memory 802. The ultrasonic deep rolling-based heat treatment rail auxiliary strengthening device 800 may also include one or more of a multimedia component 803, an I / O interface 804, and a communication component 805.

[0150] The processor 801 controls the overall operation of the ultrasonic deep rolling-based heat-treated rail auxiliary strengthening device 800 to complete all or part of the steps in the ultrasonic deep rolling-based heat-treated rail auxiliary strengthening method described above. The memory 802 stores various types of data to support the operation of the ultrasonic deep rolling-based heat-treated rail auxiliary strengthening device 800. This data may include, for example, instructions for any application or method operating on the ultrasonic deep rolling-based heat-treated rail auxiliary strengthening device 800, as well as application-related data such as contact data, sent and received messages, images, audio, video, etc. The memory 802 can be implemented using any type of volatile or non-volatile storage device or a combination thereof, such as Static Random Access Memory (SRAM), Electrically Erasable Programmable Read-Only Memory (EEPROM), Erasable Programmable Read-Only Memory (EPROM), Programmable Read-Only Memory (PROM), Read-Only Memory (ROM), magnetic storage, flash memory, magnetic disk, or optical disk. The multimedia component 803 may include a screen and an audio component. The screen may be, for example, a touchscreen, and the audio component is used to output and / or input audio signals. For example, the audio component may include a microphone for receiving external audio signals. The received audio signals may be further stored in the memory 802 or transmitted via the communication component 805. The audio component also includes at least one speaker for outputting audio signals. I / O interface 804 provides an interface between processor 801 and other interface modules, such as keyboards, mice, and buttons. These buttons can be virtual or physical. Communication component 805 is used for wired or wireless communication between the ultrasonic deep rolling-based heat-treated rail auxiliary strengthening device 800 and other devices. Wireless communication includes Wi-Fi, Bluetooth, Near Field Communication (NFC), 2G, 3G, or 4G, or a combination thereof. Therefore, the corresponding communication component 805 may include a Wi-Fi module, a Bluetooth module, or an NFC module.

[0151] In an exemplary embodiment, the ultrasonic deep rolling-based heat treatment rail auxiliary strengthening device 800 may be implemented by one or more application-specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field programmable gate arrays (FPGAs), controllers, microcontrollers, microprocessors, or other electronic components to perform the above-described ultrasonic deep rolling-based heat treatment rail auxiliary strengthening method.

[0152] In another exemplary embodiment, a computer-readable storage medium including program instructions is also provided, which, when executed by a processor, implement the steps of the ultrasonic deep rolling-based heat treatment-assisted rail strengthening method described above. For example, the computer-readable storage medium may be the memory 802 including the program instructions described above, which may be executed by the processor 801 of the ultrasonic deep rolling-based heat treatment-assisted rail strengthening device 800 to complete the ultrasonic deep rolling-based heat treatment-assisted rail strengthening method described above.

[0153] Example 4:

[0154] Corresponding to the above method embodiments, this embodiment also provides a readable storage medium. The readable storage medium described below can be referred to in conjunction with the ultrasonic deep rolling-based heat treatment rail-assisted strengthening method described above.

[0155] A readable storage medium storing a computer program, which, when executed by a processor, implements the steps of the ultrasonic deep rolling-based heat-treated rail-assisted strengthening method described in the above method embodiments.

[0156] Specifically, the readable storage medium can be a USB flash drive, a portable hard drive, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk, or any other readable storage medium capable of storing program code.

[0157] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

[0158] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A heat-treated rail-assisted strengthening method based on ultrasonic deep rolling, characterized in that, include: Obtain the hardened layer property parameters and residual stress parameters of the heat-treated rail; Based on the hardened layer property parameters and residual stress parameters, the static load, amplitude, overlap rate and number of rolling cycles required for ultrasonic deep rolling are calculated. The wheel-rail contact condition of the heat-treated rail head is obtained, and the heat-treated rail head is divided into multiple different processing areas based on the wheel-rail contact condition. The parameters of the ultrasonic deep rolling equipment are configured according to static load, amplitude, overlap rate and rolling times. After the parameters are configured, the ultrasonic deep rolling equipment performs ultrasonic deep rolling processing in different processing areas with different lateral step distances. The performance of the rails after ultrasonic deep rolling was tested to confirm that the hardness gradient and residual stress distribution after ultrasonic deep rolling met the preset indicators.

2. The heat-treated rail-assisted strengthening method based on ultrasonic deep rolling according to claim 1, characterized in that, The acquisition of the hardened layer property parameters and residual stress parameters of the heat-treated rail includes: Within the wheel-rail contact area on the rail surface, a sample is prepared by cutting along the centerline of the wheel-rail contact. Hardness tests were performed on the cross-section of the sample, and a hardness distribution curve was plotted based on the hardness test results. Based on the hardness distribution curve, the hardening layer depth, hardness, and hardness gradient are determined to obtain the hardening layer property parameters. The residual stress parameters were obtained by measuring the residual stress of the hardened layer and the residual stress of the substrate on the cross-section of the sample using an X-ray diffraction stress analyzer.

3. The heat-treated rail-assisted strengthening method based on ultrasonic deep rolling according to claim 2, characterized in that, Based on the hardened layer property parameters and residual stress parameters, the static load, amplitude, overlap rate, and number of rolling passes required for ultrasonic deep rolling are calculated, including: The static load required for ultrasonic deep rolling is calculated based on the hardened layer depth, the residual stress of the hardened layer, and the residual stress of the substrate. The amplitude value required for ultrasonic deep rolling is calculated based on the static load, hardened layer depth, and residual stress in the hardened layer. The overlap rate of the ultrasonic deep rolling path is calculated based on the percentage of residual stress in the substrate and residual stress in the hardened layer. The required number of rolling passes is calculated based on the hardness and hardness gradient of the hardened layer.

4. The heat-treated rail-assisted strengthening method based on ultrasonic deep rolling according to claim 1, characterized in that, The process involves obtaining the wheel-rail contact condition of the heat-treated rail head and dividing the heat-treated rail head into multiple different processing areas based on the wheel-rail contact condition, including: Obtain the distribution range of the wheel-rail contact light band or wheel-rail contact spot on the surface of the heat-treated rail head; The central processing area is defined as 80% of the area in the middle of the wheel-rail contact light strip or wheel-rail contact spot. The area of ​​10% on each side around the wheel-rail contact light strip or wheel-rail contact spot is designated as a transition processing zone. The area on the rail head surface that is not affected by wheel-rail contact is designated as the edge processing area.

5. The heat-treated rail-assisted strengthening method based on ultrasonic deep rolling according to claim 4, characterized in that, After parameter configuration, the ultrasonic deep rolling equipment performs ultrasonic deep rolling in different processing areas with different lateral step distances, including: The ultrasonic deep rolling equipment is controlled to perform ultrasonic deep rolling in the central processing area with a first preset lateral step distance. The ultrasonic deep rolling equipment is controlled to perform ultrasonic deep rolling in the transition processing zone with a second preset lateral step distance. The ultrasonic deep rolling equipment is controlled to perform ultrasonic deep rolling in the edge processing area with a third preset lateral step distance.

6. An auxiliary strengthening device for heat-treated steel rails based on ultrasonic deep rolling, characterized in that, include: The parameter acquisition module is used to acquire the hardened layer property parameters and residual stress parameters of the heat-treated rail; The parameter calculation module is used to calculate the static load, amplitude, overlap rate, and number of rolling cycles required for ultrasonic deep rolling based on the hardened layer property parameters and residual stress parameters. The region division module is used to obtain the wheel-rail contact condition of the heat-treated rail head and divide the heat-treated rail head into multiple different processing regions based on the wheel-rail contact condition. The processing control module is used to configure the parameters of the ultrasonic deep rolling equipment according to the static load, amplitude, overlap rate and rolling times. After the control parameters are configured, the ultrasonic deep rolling equipment performs ultrasonic deep rolling processing in different processing areas with different lateral step distances. The performance testing module is used to test the performance of the rails after ultrasonic deep rolling to confirm that the hardness gradient and residual stress distribution after ultrasonic deep rolling treatment meet the preset indicators.

7. The auxiliary strengthening device for heat-treated rails based on ultrasonic deep rolling according to claim 6, characterized in that, The parameter acquisition module includes: The sampling unit is used to cut and prepare samples along the center line of the wheel-rail contact within the wheel-rail contact area on the rail surface. The hardness testing unit is used to perform hardness testing on the cross-section of the sample and to plot a hardness distribution curve based on the hardness test results. The attribute parameter determination unit is used to determine the hardened layer depth, hardened layer hardness and hardness gradient based on the hardness distribution curve, and to obtain the hardened layer attribute parameters. The stress parameter measurement unit is used to measure the residual stress of the hardened layer and the residual stress of the substrate on the cross-section of the sample using an X-ray diffraction stress analyzer, so as to obtain the residual stress parameters.

8. The auxiliary strengthening device for heat-treated rails based on ultrasonic deep rolling according to claim 7, characterized in that, The parameter calculation module includes: The static load calculation unit is used to calculate the static load required for ultrasonic deep rolling based on the hardened layer depth, the residual stress of the hardened layer and the residual stress of the substrate. An amplitude calculation unit is used to calculate the amplitude value required for ultrasonic deep rolling based on the static load, hardened layer depth, and residual stress in the hardened layer. The overlap rate calculation unit is used to calculate the overlap rate of the ultrasonic deep rolling path based on the percentage of residual stress in the substrate and residual stress in the hardened layer. The rolling cycle calculation unit is used to calculate the required number of rolling cycles based on the hardness and hardness gradient of the hardened layer.

9. The auxiliary strengthening device for heat-treated rails based on ultrasonic deep rolling according to claim 6, characterized in that, The region division module includes: The contact range acquisition unit is used to acquire the distribution range of the wheel-rail contact light band or wheel-rail contact spot on the surface of the heat-treated rail head. The central area division unit is used to designate 80% of the central area of ​​the wheel-rail contact light strip or wheel-rail contact spot as the central processing area. The transition zone division unit is used to designate 10% of the area on each side of the wheel-rail contact light strip or wheel-rail contact spot as a transition processing zone. An edge area division unit is used to designate the area on the rail head surface that is not affected by wheel-rail contact as an edge processing area.

10. The auxiliary strengthening device for heat-treated rails based on ultrasonic deep rolling according to claim 9, characterized in that, The processing control module includes: The central processing unit is used to control the ultrasonic deep rolling equipment to perform ultrasonic deep rolling in the central processing area with a first preset lateral step distance. The transition zone processing unit is used to control the ultrasonic deep rolling equipment to perform ultrasonic deep rolling in the transition processing zone with a second preset lateral step distance. An edge processing unit is used to control the ultrasonic deep rolling equipment to perform ultrasonic deep rolling in the edge processing area with a third preset lateral step distance.

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