A laser thermal fatigue testing machine

Abstract

The application discloses a kind of laser thermal fatigue testing machines, belongs to material test technical field, including base, rotating device, heating temperature control device, circulating cooling device, driving device and control system;Heating temperature control device includes coaxial temperature measuring laser head installed on the upper surface of base, infrared thermometer is installed on the outer circumference of follow-up temperature measuring disc upper surface, shift fork switch is installed on the outer circumference of follow-up temperature measuring disc lower surface, two-way electromagnetic pin is passed through and arranged on follow-up temperature measuring disc and two electromagnetic pin blocks are respectively inserted in sample cooling disc and reverse reverse disc;Infrared thermometer carries out follow-up temperature measurement to the cooling process of sample.The application uses laser as heating source, realizes the good simulation of thermal fatigue working condition, measures the temperature of sample while heating sample, carries out follow-up temperature measurement to sample in the process of cooling, realizes the whole process monitoring and control of sample temperature.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of material testing, in particular to a laser thermal fatigue testing machine. BACKGROUND

[0002] In the process of rolling workpieces, when the hot rolling roller bites into the rolled material, the roller surface is in contact with the hot rolled material and is extruded and rubbed, the temperature rises rapidly, and after the roller surface is separated from the rolled material, it is cooled by liquid spraying, and the temperature drops. After experiencing multiple cold and hot temperature cycles, fatigue cracks and spalling occur on the surface of the roller body. Hot work die steel also has this thermal fatigue phenomenon.

[0003] The heating methods of thermal fatigue testing include resistance furnace radiation heating, flame heating, infrared heating, induction heating, and laser heating. The most commonly used method is induction heating, and the thermal fatigue testing method in the existing standard uses induction heating. A small plane is cut on the cylindrical sample, and the entire cylindrical outer surface and the plane are heated. After the thermal fatigue test is completed, the fatigue crack density and depth on the small plane are detected. This heating method is suitable for steel materials with certain toughness. For hard and brittle materials such as hot rolling rollers, fatigue several times can cause penetrating cracks. The thermal fatigue resistance of different roller materials cannot be evaluated. And due to the different permeability of the sample, the surface temperature field of the induction heating is different, and for some paramagnetic phase materials, the performance is particularly obvious. And when the surface heating temperature exceeds the Curie point, the induction heating layer will suddenly become deep, causing the temperature field to change suddenly, and then the thermal fatigue damage degree of the Curie point above and below the temperature will change. Therefore, the applicable temperature range is small. SUMMARY

[0004] The technical problem to be solved by the present application is to provide a laser thermal fatigue testing machine, which uses laser as a heating source to realize good simulation of thermal fatigue working conditions, measures the temperature of the sample while heating the sample, and measures the temperature of the sample during cooling to realize full-process monitoring and control of the temperature of the sample.

[0005] To solve the above technical problems, the technical scheme adopted by the present application is:

[0006] A laser thermal fatigue testing machine, comprising a base, a rotating device arranged on the upper part of the base to drive the sample to rotate, a heating and temperature control device arranged on the outer side of the rotating device to heat and measure the temperature of the sample, a circulating cooling device to cool the sample, a driving device arranged in the interior of the base to drive the rotating device to move, and a control system.

[0007] The heating temperature control device comprises a coaxial temperature measurement laser head installed on the upper surface of the base, an infrared temperature measurement instrument installed on the outer circumferential upper surface of the follow-up temperature measurement disc, a fork switch installed on the outer circumferential lower surface of the follow-up temperature measurement disc, a two-way electromagnetic pin penetratingly arranged on the follow-up temperature measurement disc, and two electromagnetic pin blocks respectively inserted into the sample cooling disc and the reverse rotation disc.

[0008] Further improvement of the technical scheme of the present application is that the driving device comprises a coaxial reverse bevel gear set installed in the base and a servo motor driving the coaxial reverse bevel gear set.

[0009] Further improvement of the technical scheme of the present application is that the bevel gear comprises a lower gear driving a thin-diameter inner shaft and an upper gear driving a thick-diameter hollow shaft, the thick-diameter hollow shaft is sleeved outside the thin-diameter inner shaft, the thin-diameter inner shaft is higher than the thick-diameter hollow shaft, and a through hole for cooling water return is penetratingly arranged at the center of the thin-diameter inner shaft.

[0010] Further improvement of the technical scheme of the present application is that the rotating device comprises a sample cooling disc fixedly connected with the upper surface of the thin-diameter inner shaft and a reverse rotation disc fixedly connected with the upper surface of the thick-diameter hollow shaft, and a plurality of rotation disc block holes for inserting the electromagnetic pin block are uniformly arranged on the reverse rotation disc.

[0011] Further improvement of the technical scheme of the present application is that the sample cooling disc is a bowl-shaped disc with an outer wall arranged on the outer circumferential surface, samples are uniformly arranged on the outer surface of the outer wall, a drain hole for draining water is arranged at the center of the disc, and a plurality of sample disc block holes for inserting the electromagnetic pin block are uniformly arranged on the disc.

[0012] Further improvement of the technical scheme of the present application is that the circulating cooling device comprises a water collecting tank installed below the thin-diameter inner shaft, a cold water machine connected with the water collecting tank, and a spraying pipe connected with the cold water machine, and the outlet of the spraying pipe is aligned with the inner side of the outer wall of the sample cooling disc.

[0013] Further improvement of the technical scheme of the present application is that the follow-up temperature measurement disc is installed between the sample cooling disc and the reverse rotation disc and connected with the thin-diameter inner shaft bearing.

[0014] Further improvement of the technical scheme of the present application is that the temperature measurement points of the coaxial temperature measurement laser head and the infrared temperature measurement instrument are located on the same horizontal plane as the samples on the sample cooling disc.

[0015] Further improvement of the technical scheme of the present application is that the bidirectional electromagnetic pin, the sample disc block hole and the reverse disc block hole are equal in distance from the axis of the thin-diameter inner shaft.

[0016] Further improvement of the technical scheme of the present application is that the infrared temperature measuring instrument and the shift fork switch are located on the same vertical line.

[0017] Thanks to the above technical scheme, the present application has the following technical progress:

[0018] 1. The present application realizes good simulation of the cold and hot fatigue working condition by setting the laser to scan and heat the rotating sample, which is very close to the heating condition of the contact material of the hot rolling working roll.

[0019] 2. The present application ensures the consistency of the peak temperature of the sample surface by setting the coaxial temperature measuring laser head to heat the sample and measure the temperature of the sample at the same time.

[0020] 3. The present application realizes the whole tracking of the cooling process of the sample surface after heating by setting the follow-up temperature measuring device, so as to feedback control the cooling parameters and perform the water shortage and over-temperature alarm parking.

[0021] 4. The present application controls the temperature of the sample cooling process by the circulating cooling device, so as to keep the cooling water temperature constant and stabilize the sample cooling condition.

[0022] 5. The present application realizes the performance comparison of multiple samples under the same test condition by arranging a plurality of samples on the sample cooling disc. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 is the front view of the laser thermal fatigue testing machine in the present application;

[0024] Figure 2 is the top view of the laser thermal fatigue testing machine in the present application;

[0025] Among them, 1 is a servo motor, 2 is a coaxial reverse bevel gear set, 3 is a base, 4 is a limit top block, 5 is a coaxial temperature measuring laser head, 6 is a follow-up temperature measuring disc, 7 is a sample, 8 is a sample cooling disc, 9 is a follow-up infrared temperature measuring instrument, 10 is a bidirectional electromagnetic pin, 11 is a reverse reverse disc, 12 is a water collecting tank, 13 is a water chiller, 14 is a spray pipe, 15 is a sample disc block hole, 16 is a reverse disc block hole, and 17 is a shift fork switch. DETAILED DESCRIPTION

[0026] The present application will be further described in detail below in combination with the drawings and embodiments:

[0027] In the description of the present application, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

[0028] In the description of the present application, "several" means at least one, for example, one, two, etc., unless otherwise explicitly and specifically limited.

[0029] As shown in Figure 1 , Figure 2 , a laser thermal fatigue testing machine, comprising a base 3, a rotating device arranged on the upper part of the base 3 to drive the sample 7 to rotate, a heating and temperature control device arranged outside the rotating device to heat and measure the temperature of the sample 7, a circulating cooling device to cool the sample 7, a driving device arranged inside the base 3 to drive the rotating device to move, and a control system.

[0030] The driving device comprises a coaxial reverse bevel gear set 2 mounted inside the base 3 and a servo motor 1 driving the coaxial reverse bevel gear set 2; the coaxial reverse bevel gear set 2 comprises a horizontal-axis main bevel gear and two vertical-axis coaxial slave bevel gears driven by the main bevel gear to rotate in the same speed in both directions.

[0031] The slave bevel gear comprises a lower gear driving a thin-diameter inner shaft and an upper gear driving a thick-diameter hollow shaft; the thick-diameter hollow shaft is sleeved outside the thin-diameter inner shaft; the thin-diameter inner shaft is higher than the thick-diameter hollow shaft, and a through hole for cooling water return is arranged at the center of the thin-diameter inner shaft.

[0032] The rotating device comprises a sample cooling disc 8 fixedly connected with the upper surface of the thin-diameter inner shaft and a reverse back disc 11 fixedly connected with the upper surface of the thick-diameter hollow shaft; the reverse back disc 11 is uniformly provided with a plurality of back disc block holes 16 for inserting and placing electromagnetic pin blocks.

[0033] The sample cooling disc 8 is a bowl-shaped disc with an outer wall arranged on the outer circumference, and the material is red copper; the sample 7 is uniformly arranged on the outer surface of the outer wall, and the method for arranging the sample 7 includes fixed modes such as inlaying and clamping; a plurality of sample disc block holes 15 for inserting and placing electromagnetic pin blocks are uniformly arranged on the disc, and a drain hole for draining water is arranged at the center of the disc.

[0034] The circulating cooling device comprises a water collecting tank 12 installed below the inner shaft, a water chiller 13 connected with the water collecting tank 12, and a spray pipe 14 connected with the water chiller 13, and the outlet of the spray pipe 14 is aligned with the inner side of the outer wall of the sample cooling disc 8.

[0035] The heating temperature control device comprises a coaxial temperature measuring laser head 5 installed on the upper surface of the base 3, an infrared temperature measuring instrument 9 installed on the outer circumferential upper surface of the follow-up temperature measuring disc 6, a fork switch 17 installed on the outer circumferential lower surface of the follow-up temperature measuring disc 6, a two-way electromagnetic pin 10 penetratingly arranged on the follow-up temperature measuring disc 6, and two electromagnetic pin blocks respectively inserted on the sample cooling disc 8 and the reverse rotation disc 11; the infrared temperature measuring instrument 9 performs follow-up temperature measurement on the cooling process of the sample 7.

[0036] The temperature measuring points of the coaxial temperature measuring laser head 5 and the infrared temperature measuring instrument 9 are located on the same horizontal plane as the sample 7 on the sample cooling disc 8; the two-way electromagnetic pin 10, the sample disc block hole 15 and the reverse disc block hole 16 are equidistant from the center of the inner shaft; the infrared temperature measuring instrument 9 is located on the same vertical line as the fork switch 17; when the electromagnetic pin block on the sample cooling disc 8 drives the follow-up temperature measuring disc 6 to rotate, the infrared temperature measuring instrument 9 is located on the same horizontal line as a sample 7.

[0037] The control system is used to control the rotation speed, rotation number, program action of the two-way electromagnetic pin 10 and the limiting top block 4 of the servo motor 1, the power of the water pump of the water collecting tank 12, the start-stop of the water chiller 13, the adjustment of the cooling water flow rate, and the laser output power of the coaxial temperature measuring laser head 5 is adjusted by measuring the heating peak temperature of the sample surface through the coaxial temperature measuring laser head 5, and the circulating cooling device is adjusted by measuring the cooling temperature of the sample surface through the infrared temperature measuring instrument 9.

[0038] The working process of the laser thermal fatigue testing machine is as follows:

[0039] The inner shaft with fine diameter drives the sample cooling disc 8 clamping the sample 7 to rotate forward, and the hollow shaft with coarse diameter drives the reverse rotation disc 11 to rotate reversely; the coaxial temperature measuring laser head 5 heats the sample 7 rotating to the front thereof, and simultaneously measures the temperature of the sample 7 in the heating state.

[0040] After the sample 7 is heated by the coaxial temperature measuring laser head 5, the sample cooling disc 8 rotates forward, and the cooling process begins; at this time, the two-way electromagnetic pin 10 on the follow-up temperature measuring disc 6 extends upward, is driven by the electromagnetic pin block on the sample cooling disc 8, and rotates forward together with the sample cooling disc 8; the infrared temperature measuring instrument 9 on the sample cooling disc 8 continuously measures the temperature of a sample 7.

[0041] When the fork switch 17 is rotated forward to the limit block 4 at the heating inlet end, the fork switch 17 is touched, causing the change of the on-off state of the two-way electromagnetic pin 10, the two-way electromagnetic pin 10 extends downward, is driven by the electromagnetic pin block on the reverse rotating disc 11, and rotates reversely with the reverse rotating disc 11.

[0042] When the fork switch 17 is rotated reversely to the limit block 4 at the heating outlet end, the fork switch 17 is touched, causing the change of the on-off state of the two-way electromagnetic pin 10, the two-way electromagnetic pin 10 extends upward, is driven by the electromagnetic pin block on the sample cooling disc 8, rotates forward with the sample cooling disc 8, and repeats the continuous temperature measurement process on a sample 7.

[0043] The follow-up temperature measurement mode of the infrared temperature measuring instrument 9 realizes the whole tracking of the cooling process of the sample 7 after heating, feeds back the measurement result to the control system, controls the circulating cooling device to control the cooling parameter, and can perform water shortage and over-temperature alarm parking.

[0044] The spray pipe 14 sprays cooling water to the inner side of the outer wall of the sample cooling disc 8, is returned to the water collecting tank 12 through the through hole, is pumped into the cooling water machine 13, is cooled after heat exchange, is sprayed to the sample cooling disc 8, cools the sample 7, ensures that the whole sample 7 is not more than 80 DEG C, and realizes good cold and hot fatigue test effect.

[0045] As described above, the application adopts laser as a heating source, realizes good simulation of thermal fatigue working conditions, measures the sample temperature while heating the sample, performs follow-up temperature measurement on the sample in the cooling process, realizes whole process monitoring and control of the sample temperature.

Claims

1. A laser thermal fatigue testing machine, characterized in that: It comprises a base (3), a rotating device arranged on the upper part of the base (3) for driving the sample (7) to rotate, a heating and temperature control device arranged outside the rotating device for heating and measuring the temperature of the sample (7), a circulating cooling device for cooling the sample (7), a driving device and a control system arranged inside the base (3) for driving the rotating device to move; The driving device comprises a coaxial reverse bevel gear set (2) installed inside a base (3) and a servo motor (1) driving the coaxial reverse bevel gear set (2); the coaxial reverse bevel gear set (2) comprises a main bevel gear with a horizontal axis and two coaxial slave bevel gears with vertical axes driven by the main bevel gear to rotate in both directions at the same speed; the slave bevel gears comprise a lower gear driving a small diameter inner shaft and an upper gear driving a large diameter hollow shaft; the large diameter hollow shaft is sleeved on the outside of the small diameter inner shaft; the small diameter inner shaft is higher than the large diameter hollow shaft, and a through hole for cooling water return is provided at the center of the small diameter inner shaft; The rotating device comprises a sample cooling disk (8) fixedly connected to the upper surface of the thin-diameter inner shaft and a reverse rotating disk (11) fixedly connected to the upper surface of the thick-diameter hollow shaft; a plurality of reverse rotating disk block holes (16) for inserting and placing electromagnetic pin blocks are evenly arranged on the reverse rotating disk (11); The heating and temperature control device comprises a coaxial temperature measuring laser head (5) mounted on the upper surface of the base (3), an infrared thermometer (9) mounted on the upper surface of the outer circumference of the follow-up temperature measuring disk (6), a fork switch (17) mounted on the lower surface of the outer circumference of the follow-up temperature measuring disk (6), a bidirectional electromagnetic pin (10) penetrating the follow-up temperature measuring disk (6), and two electromagnetic pin blocks respectively inserted into the sample cooling disk (8) and the reverse return disk (11); the follow-up temperature measuring disk (6) is mounted between the sample cooling disk (8) and the reverse return disk (11) and connected to the thin-diameter inner shaft bearing; the infrared thermometer (9) performs follow-up temperature measurement on the cooling process of the sample (7).

2. A laser thermal fatigue testing machine according to claim 1, characterized in that: The sample cooling disk (8) is a bowl-shaped disk with an outer wall provided on the outer circumference, and the samples (7) are evenly arranged on the outer surface of the outer wall. A drainage hole for drainage is provided at the center of the disk, and a plurality of sample disk block holes (15) for inserting and placing electromagnetic pin blocks are evenly provided on the disk.

3. A laser thermal fatigue testing machine according to claim 2, characterized in that: The circulating cooling device comprises a water collecting tank (12) installed below the thin-diameter inner shaft, a water chiller (13) connected to the water collecting tank (12), and a spray pipe (14) connected to the water chiller (13), wherein the outlet of the spray pipe (14) is aligned with the inner side of the outer wall of the sample cooling plate (8).

4. The laser thermal fatigue testing machine according to claim 2, characterized in that: The temperature measuring points of the coaxial temperature measuring laser head (5) and the infrared thermometer (9) are located on the same horizontal plane as the sample (7) on the sample cooling plate (8).

5. The laser thermal fatigue testing machine according to claim 2, characterized in that: The bidirectional electromagnetic pin (10), the sample disk stopper hole (15), and the reversing disk stopper hole (16) are equidistant from the axis of the thin-diameter inner shaft.

6. The laser thermal fatigue testing machine according to claim 1, characterized in that: The infrared thermometer (9) and the fork switch (17) are located on the same vertical line.

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