CN106568644A - Thermal simulated test machine continuous casting billet high-temperature tensile test sample, and clamping method thereof - Google Patents

Abstract

The invention relates to a thermal simulation testing machine continuous casting slab high-temperature tensile test sample and a clamping method thereof. The sample has a sample round rod, the length of the sample round rod is 120mm, and there is a limit round head at both ends of the round rod. The thickness of the limit round head is 10mm, and the diameter of the limit round head is not less than 18mm. There is an intermediate rod between the two limiting round heads. The diameter of the intermediate rod is 10mm. There is a bearing pad at both ends of the intermediate rod. The bearing pad is close to the limiting round head; the bearing pad is circular and has a thickness of 5mm. , there is a radial groove with a width of not less than 10.5mm on the bearing block, and the bottom of the radial groove is an arc groove bottom. The clamping method is to insert the radial groove of the bearing pad into the middle rod of the sample, and respectively close the limit round heads at both ends of the sample; close the two pairs of tensile copper clamps on the thermal simulation testing machine and the middle rod together and hold them tightly. . The sample and the clamping method of the present invention avoid cracking and fully meet the thermoplasticity research of the sample material of the continuous casting slab.

Description

A thermal simulation testing machine continuous casting slab high temperature tensile test sample and its clamping method

technical field

The invention relates to a thermal simulation testing machine continuous casting slab high-temperature tensile test sample and a clamping method thereof.

Background technique

In the iron and steel metallurgical production process, in order to formulate the correct continuous casting process parameters, it is necessary to study the influence of temperature, strain rate and cooling rate on the reduction of area. Generally, high temperature tensile tests are used to study the thermoplasticity of continuous casting slabs of iron and steel materials. According to the specifications of the copper fixture provided by the manufacturer of the thermal simulation testing machine and the requirements for the length of the uniform temperature zone, the size of the high-temperature tensile sample is required to be Φ10mm×120mm, and the two ends of the head have a 15mm long thread, and the two ends of the thread are screwed on the sleeve. The nut is easy to stretch and apply load. The cold working performance of the sample must meet the requirements of machining sample preparation and the thread cannot be cracked to meet the assembly requirements of the machine test. However, for the continuous casting slabs of some steel materials, due to the coarse grain size or uneven distribution of the internal structure, when the machining samples are prepared, the threads at both ends are severely cracked and the standard threads cannot be completed, resulting in such The research on thermoplasticity of steel types cannot be carried out, and cannot provide theoretical support for the formulation of continuous casting process on the production site, which greatly affects the development progress and stable production of this type of material.

Contents of the invention

In order to overcome the shortcoming of cracking in the existing thermal simulation testing machine continuous casting slab high temperature tensile test sample, the present invention provides a thermal simulation testing machine continuous casting slab high temperature tensile test sample that avoids cracking, the sample structure is simple, The free span after assembly on the thermal simulation test machine and the length of the uniform temperature zone after heating are completely consistent with the samples required by the thermal simulation manufacturer, which fully meets the thermoplasticity research of the continuous casting slab sample material.

Another object of the present invention is to provide a method for clamping a specimen for a high-temperature tensile test of a continuous casting slab in a thermal simulation testing machine.

The thermal simulation testing machine has a sample round bar as a whole for the continuous casting slab high temperature tensile test sample. Compatible), there is a limit round head at both ends of the round rod, the thickness of the limit round head along the length direction of the round rod is 10mm, and the diameter of the limit round head is not less than 18mm (this size can better bear the pull The force during the tensile test), the diameter of the limit round head should not be greater than 40mm, otherwise it will affect the installation of the light-duty stainless steel fixture on the machine. Between the two limiting round heads is the middle rod, the diameter of the middle rod is 10mm, and there is a bearing pad at both ends of the middle rod, and the bearing pad is close to the limiting round head; the bearing pad is circular, The thickness is 5mm, and the diameter of the bearing block is not less than Φ20mm. Generally, the diameter is Φ40mm±5mm. If the diameter exceeds 45mm, it will affect the installation of light-duty stainless steel fixtures on the machine. There is a radial groove with a width of not less than 10.5mm on the bearing block, the bottom of the radial groove is an arc groove bottom, and the radius of the arc groove bottom is not less than 5.25mm.

The aforementioned thermal simulation testing machine continuous casting slab high temperature tensile test sample is characterized in that: the surface roughness of the sample round bar and the bearing block is Ra≤3.2 μm.

The aforementioned thermal simulation testing machine continuous casting slab high-temperature tensile test sample is characterized in that: the center of the circular arc groove bottom is concentric with the center of the bearing block.

The clamping method of the continuous casting slab high temperature tensile test sample of this thermal simulation testing machine, the thermal simulation testing machine carries out the continuous casting slab high temperature tensile test sample and (test round bar and bearing pad) the manufacturer's original tensile copper clip Combined assembly use.

On the flat workbench, insert the radial slots of the two bearing pads into the middle rod of the sample, and respectively close to the limit round heads at both ends of the sample.

There are two tensile copper fixtures on the left and right (commonly called wedge-shaped tensile copper fixtures) on the thermal simulation testing machine Gleeble 3800. Each tensile copper fixture has two upper and lower fixture semicircular blocks, and the two fixture semicircular pieces are combined to form a copper fixture. hole. Close the two jig semicircular blocks and the middle rod on the two pairs of tensile copper jigs and hold them tightly, and the outer end faces of the copper jigs are respectively close to the bearing pads at both ends of the sample. At this point, the clamping of the sample on the flat workbench is completed, and the clamped sample is installed in the vacuum chamber of the thermal simulation testing machine.

This is compatible with the assembly method of the 120mm-long, 15mm-threaded high-temperature tensile specimen at both ends provided by the manufacturer of the thermal simulation testing machine on a flat workbench, and the same 30mm free span and 10mm uniform temperature zone are obtained. By the clamping method of the continuous casting slab high temperature tensile test sample of the above-mentioned thermal simulation testing machine, the thermal simulation testing machine of the present invention is carried out the continuous casting slab high temperature tensile test sample and carries out tensile test, obtained the free span of 30mm and The uniform temperature zone of 10mm is completely consistent with the 120mm long high-temperature tensile specimen with 15mm threads at both ends provided by the manufacturer of the thermal simulation testing machine. The obtained 30mm free span and 10mm uniform temperature zone are completely consistent, and the obtained temperature gradient is completely consistent. Thus ensuring the accuracy and stability of the thermal processing data results.

The above-mentioned clamping method of the continuous casting slab high temperature tensile test sample in the thermal simulation testing machine, the model of the thermal simulation testing machine is Gleeble 3800.

In the above-mentioned clamping method of the continuous casting slab high-temperature tensile test sample in the thermal simulation testing machine, when clamping the sample, it should be used in combination with the bearing pad and the tensile copper clamp.

Beneficial Effects of the Invention

Utilize the thermal simulation testing machine continuous casting slab high-temperature tensile test sample and its clamping method of the present invention, avoid cracking and carry out thermoplasticity research on the thermal simulation testing machine, and assemble the bearing cushion block and the tensile copper clamp for combined assembly and use at the same time, which can be used. Obtain a steeper temperature gradient, and obtain a high-temperature tensile sample with a length of 120mm and 15mm threads at both ends provided by the manufacturer of the thermal simulation testing machine. The obtained 30mm free span and 10mm uniform temperature zone are completely consistent, thus ensuring thermal processing The data results are accurate and stable. The sample described in the present invention is simple and convenient to assemble, and the two added load bearing pads are easy to process and can be reused; the process of using the sample of the present invention to carry out thermoplastic research on the subsequent machine is completely consistent with the research method provided by the original manufacturer , the data measured by the high-temperature tensile test are convenient to draw the curve relationship between the deformation temperature and the reduction of area Z, evaluate the thermoplastic properties of the continuous casting slab during the cooling process after solidification, and provide theoretical support for the formulation of continuous casting process parameters. Provide basic protection for preventing defects such as continuous casting slab cracks.

Description of drawings

Fig. 1 is the front view of the continuous casting slab high temperature tensile test sample of this thermal simulation testing machine.

Fig. 2 is a shape diagram of a spacer.

Figure 3 is the installation diagram of the continuous casting slab high temperature tensile test sample in the copper fixture of this thermal simulation testing machine, and the part is cut away in the figure.

Figure 4 is the left view of the copper fixture in Figure 3

In the above figure:

1. Sample round rod, 2. Limiting round head, 3. Bearing pad, 4. Intermediate rod, 5. Radial groove, 6. Arc groove bottom, 7. Tensile copper fixture, 8. Thermal simulation test Continuous casting slab high temperature tensile test sample, 9. Copper fixture seam, 10. Copper fixture butt hole, 11. Copper fixture outer end face, 12. Fixture semicircle block.

Fig. 5 Tensile test curve with a deformation temperature of 1200°C.

Fig. 6 Tensile test curve of deformation temperature 1100°C.

Fig. 7 Tensile test curve of deformation temperature 1000°C.

Fig. 8 Tensile test curve with a deformation temperature of 900°C.

Fig. 9 Tensile test curve of deformation temperature 800°C.

detailed description

The specific implementation of the present invention will be described in detail below in conjunction with the examples and accompanying drawings, but the specific implementation of the present invention is not limited to the following examples. All technical solutions formed by equivalent replacement or equivalent transformation fall within the scope of protection required by the present invention.

Sample Example

In this embodiment, the high-temperature tensile test sample of continuous casting slab is used in the thermal simulation testing machine, and the sample is directly applied to the thermal simulation testing machine Gleeble 3800 to perform the high-temperature tensile test. In this embodiment, the test material is iron-silicon-boron amorphous master alloy, and 304 stainless steel is selected as the material of the bearing block.

The shape of the high-temperature tensile test sample for the continuous casting slab of this thermal simulation testing machine is shown in Figure 1. It has a sample round bar 1, the total length of the sample round bar 1 is 120mm (including the limit round head 2), and the sample round bar 1 There is a limit round head 2 at both ends of each. The thickness of the limit round head 2 along the length direction of the round rod is 10mm, and the diameter is Φ18mm. Between the two limit round heads 2 is an intermediate rod 4, and the middle rod 4 The diameter is Φ10mm, and there is a bearing pad 3 at both ends of the middle rod 4, and the bearing pad 3 is close to the limit round head 2.

The bearing block 3 is circular and the thickness is 5mm. The diameter of the bearing block 3 is Φ40mm. There is a U-shaped radial groove 5 with a width of 10.5mm on the bearing block 3. The bottom of the radial groove 5 is an arc groove. Bottom 6, the center of circle of arc groove bottom 6 is concentric with the center of circle of bearing block 3, and the radius of arc groove bottom 6 is 5.25mm, see Fig. 2.

In this embodiment, the surface roughness of the sample round rod 1 and the bearing block 3 is Ra=3.2 μm.

Embodiment of clamping method

On the flat workbench, insert the radial slots 5 of the two bearing pads 3 into the middle rod 4 of the sample, and respectively close to the limit round heads 2 at both ends of the sample.

There are two tensile copper fixtures 7 on the left and right (usually called wedge-shaped tensile copper fixtures) on the thermal simulation testing machine Gleeble 3800. Each tensile copper fixture 7 has two upper and lower clamp semicircular blocks 12, and the two clamp semicircular blocks 12 are combined to form The copper clamp fits the holes 10 . Close the two jig semicircular blocks 12 and the middle rod 4 on the two pairs of tensile copper jigs 7 and hold them tightly, and the outer end surfaces 11 of the copper jigs are respectively close to the bearing pads 3 at both ends of the sample, see Figure 3 and Figure 4 . At this point, the clamping of the sample on the flat workbench is completed, and the clamped sample is installed in the vacuum chamber of the thermal simulation testing machine, which is the same as the high-temperature thread with a length of 120mm and 15mm at both ends provided by the manufacturer of the thermal simulation testing machine. The same 30mm free span and 10mm uniform temperature zone were obtained by adapting the assembly method of the tensile specimen on the flat workbench. The rest of the machine installation sample method is consistent with the original manufacturer.

Through the thermal simulation testing machine continuous casting slab high-temperature tensile test sample and the clamping method provided by the present invention, the test can be carried out according to the research method of thermal simulation testing machine Gleeble3800 thermoplasticity, and the set process route is: at 10 ° C / s Heating speed Heat the sample to the deformation temperature, keep it warm for 5 minutes, and then break the sample at a strain rate of 1S ^-1 . The deformation temperatures are 1200°C, 1100°C, 1000°C, 900°C, and 800°C. Immediately spray a large amount of water on the fracture to maintain the original appearance of the fracture. During the test, data parameters such as TC1 temperature, Force value, and Stroke displacement are collected, and the collected data parameters are drawn into the tensile test curves in Figures 5 to 9. The free span of 30mm can be obtained by using the present invention, and the uniform temperature zone of 10mm is obtained in the heating stage, which is free from the 30mm free span of the high-temperature tensile sample with a sample length of 120mm and two ends of the sample provided by the manufacturer of the thermal simulation testing machine. The span is completely consistent with the 10mm uniform temperature zone, and the obtained temperature gradient is completely consistent, thus ensuring the accuracy of the thermal processing data.

After the test is over, through the collected data parameters and tensile test curves, read out the force value parameters at different temperatures, and calculate the ultimate strength at different temperatures; through the measurement of the fracture of the sample, you can obtain the ultimate strength at different temperatures. Reduction of area; After the fracture, the sample is cut off in the uniform temperature zone by a wire cutting machine, and the fracture morphology and structure analysis can be carried out.

Except for the above-mentioned embodiments, all technical solutions formed by equivalent replacement or equivalent transformation fall within the scope of protection required by the present invention.

Claims (4)

1. A thermal simulation testing machine continuous casting slab high temperature tensile test sample, it has a sample round bar, its characteristics are: the total length of the sample round bar is 120mm, and there is a limit circle at each end of the round bar The thickness of the limit round head along the length direction of the round rod is 10mm, the diameter of the limit round head is not less than 18mm, and the diameter of the limit round head cannot be greater than 40mm; between the two limit round heads is the middle rod, the middle The diameter of the rod is 10mm, and there is a bearing block at both ends of the middle rod, and the bearing block is close to the limit round head; the bearing block is circular, the thickness is 5mm, and the diameter of the bearing block is not less than Φ20mm; There is a radial groove with a width of not less than 10.5mm on the spacer, the bottom of the radial groove is an arc groove bottom, and the radius of the arc groove bottom is not less than 5.25mm. 2. The thermal simulation testing machine continuous casting slab high temperature tensile test sample according to claim 1, characterized in that: the surface roughness of the sample round bar and the bearing block is Ra≤3.2μm. 3. The thermal simulation testing machine continuous casting slab high temperature tensile test sample according to any one of claims 1 or 2, characterized in that: the center of the circular arc groove bottom is concentric with the center of the bearing block. 4. A clamping method for a thermal simulation testing machine continuous casting slab high-temperature tensile test sample, which is to insert the radial grooves of two bearing pads into the middle rod of the sample, and respectively close to the two ends of the sample limit round head; There are left and right tensile copper fixtures on the thermal simulation testing machine, each tensile copper fixture has two upper and lower fixture semicircular blocks, and the two fixture semicircular blocks are combined to form copper fixture matching holes; two pairs of tensile copper fixtures are combined The semi-circular block of the first clamp and the middle rod are closed tightly, and the outer end faces of the copper clamp are respectively close to the load-bearing pads at both ends of the sample. Inside the vacuum chamber of the testing machine.