High throughput coating thermal expansion coefficient and residual stress tester

Abstract

The application discloses a high-flux coating thermal expansion coefficient and residual stress tester and relates to the technical field of thermal performance evaluation of coatings and composite materials. The high-flux coating thermal expansion coefficient and residual stress tester comprises a computer and a testing machine electrically connected with the computer. The testing machine comprises a high-temperature clamp, a machine body, a top rod, an L-shaped support frame, a first displacement sensor, a first sliding rail, a first sliding block, a third sliding rail, a third sliding block, a first cross rod, a first threaded sleeve, a first screw rod, a second cross rod, a second sliding rail, a second sliding block, a fourth cross rod, a second threaded sleeve, a second screw rod, a second servo motor, a first spring, a vertical rod, a third cross rod, a second spring, a second displacement sensor and a first servo motor. The force control structure is arranged, external force interference is avoided, no interaction force is generated between the top rod and the sample or constant force is kept, and therefore, the accuracy of displacement measurement is ensured.

Description

Technical Field

[0001] This invention relates to the field of thermal performance evaluation technology for coatings and composite materials, and in particular to a high-throughput tester for the coefficient of thermal expansion and residual stress of coatings. Background Technology

[0002] Ceramic coatings are widely used in aerospace, military, automotive, petrochemical, and various high-temperature wear-resistant components. For example, wear-resistant and high-temperature components such as engines and bearings often have ceramic coatings as a protective layer. In the chemical industry, ceramic coatings are applied to the inner walls of many pipes through which corrosive liquids pass, increasing their lifespan and durability several times over. In the defense and metallurgical industries, many high-temperature components require thermal barrier coatings to withstand high or ultra-high temperatures and oxidative corrosion. Due to the difference in the coefficients of thermal expansion between the coating and the substrate material, residual stress often occurs at the coating and interface. Therefore, material design, structural design, and finite element analysis of thermal stress and deformation all require prior knowledge of the elastic modulus and coefficients of thermal expansion of both the coating and the substrate. Current technologies mostly use the push-rod method to measure expansion displacement, then import the data into a computer to calculate the coefficient of thermal expansion and residual stress. During the push-rod method, the sample expansion causes the push-rod to move, generating displacement. However, in actual equipment, the push-rod is subject to external forces (such as gravity and friction), causing interaction forces between the push-rod and the sample, thus affecting the accuracy of the displacement measurement. Summary of the Invention

[0003] The main objective of this invention is to provide a high-throughput coating thermal expansion coefficient and residual stress tester to solve the above-mentioned problems.

[0004] To achieve the above objectives, the present invention provides a high-throughput coating thermal expansion coefficient and residual stress tester, comprising a computer and a testing machine electrically connected to the computer; the testing machine includes a body, the top of which is provided with a high-temperature fixture for placing samples; an L-shaped support frame is provided inside the body; a first slide rail and a second slide rail are vertically arranged sequentially from top to bottom on one side of the L-shaped support frame; a first slider is slidably arranged on the first slide rail, a third slide rail is fixedly arranged on the first slider, a third slider is slidably arranged on the third slide rail, and a first crossbar is fixedly arranged on the third slider; a top rod is connected to the first crossbar, the top rod extends into the high-temperature fixture and abuts against the sample; a second crossbar is fixedly connected to the bottom of the third slide rail, a first servo motor is arranged on the second crossbar, and the output shaft of the first servo motor is connected to... The system comprises: a first screw, a first threaded sleeve adapted to the first screw fixedly mounted on the first crossbar; a vertical rod fixedly connected to the bottom of the second crossbar, and a third crossbar fixedly connected to the bottom of the vertical rod; a first displacement sensor mounted on the top of the inner side of the machine body, the telescopic rod of the first displacement sensor being fixedly connected to the top of the third slide rail; a second slider slidably mounted on the second slide rail, a fourth crossbar fixedly mounted on the second slider, a second displacement sensor fixedly mounted on the fourth crossbar, the telescopic rod of the second displacement sensor being fixedly connected to the second crossbar; a second servo motor fixedly mounted at the bottom of the L-shaped support frame, a second screw connected to the output shaft of the second servo motor, and a second threaded sleeve adapted to the second screw fixedly mounted on the fourth crossbar; and a first spring positioned between the fourth crossbar and the third crossbar.

[0005] Furthermore, a second spring is provided between the first crossbar and the third crossbar.

[0006] Furthermore, the top rod is a ceramic rod.

[0007] Furthermore, both the first displacement sensor and the second displacement sensor are LVDT sensors.

[0008] The present invention has the following beneficial effects:

[0009] This invention, by setting a force control structure, avoids external force interference, ensuring that there is no interaction force between the push rod and the sample or that the force remains constant, thereby guaranteeing the accuracy of displacement measurement. Attached Figure Description

[0010] Figure 1 This is a schematic diagram of the high-throughput coating thermal expansion coefficient and residual stress tester of the present invention.

[0011] Among them, 1-high temperature fixture; 2-sample; 3-body; 4-top rod; 5-L-shaped support frame; 6-first displacement sensor; 7-first slide rail; 8-first slider; 9-third slide rail; 10-third slider; 11-first crossbar; 12-first screw sleeve; 13-first screw; 14-second crossbar; 15-second slide rail; 16-second slider; 17-fourth crossbar; 18-second screw sleeve; 19-second screw; 20-second servo motor; 21-first spring; 22-vertical rod; 23-third crossbar; 24-second spring; 25-second displacement sensor; 26-first servo motor. Detailed Implementation

[0012] To achieve the above objectives and effects, the technical means and structure adopted by the present invention will be described in detail with reference to the accompanying drawings, focusing on the features and functions of the preferred embodiments of the present invention.

[0013] like Figure 1As shown, this invention provides a high-throughput coating thermal expansion coefficient and residual stress tester, comprising a computer and a testing machine electrically connected to the computer; the testing machine includes a body 3, with a high-temperature fixture 1 for placing a sample 2 on the top of the body 3; an L-shaped support frame 5 is provided inside the body 3; a first slide rail 7 and a second slide rail 15 are vertically arranged from top to bottom on one side of the L-shaped support frame 5; a first slider 8 is slidably arranged on the first slide rail 7, a third slide rail 9 is fixedly arranged on the first slider 8, a third slider 10 is slidably arranged on the third slide rail 9, and a first crossbar 11 is fixedly arranged on the third slider 10; a top rod 4 is connected to the first crossbar 11, the top rod 4 extends into the high-temperature fixture 1 and abuts against the sample 2; a second crossbar 14 is fixedly connected to the bottom of the third slide rail 9, and a first servo motor 26 is arranged on the second crossbar 14, with the output shaft of the first servo motor 26... A first screw 13 is connected to the first crossbar 11, and a first threaded sleeve 12 adapted to the first screw 13 is fixedly installed on the first crossbar 14; a vertical rod 22 is fixedly connected to the bottom of the second crossbar 14, and a third crossbar 23 is fixedly connected to the bottom of the vertical rod 22; a first displacement sensor 6 is installed on the top of the inner side of the machine body 3, and the telescopic rod of the first displacement sensor 6 is fixedly connected to the top of the third slide rail 9; a second slider 16 is slidably installed on the second slide rail 15, and a fourth crossbar 17 is fixedly installed on the second slider 16; a second displacement sensor 25 is fixedly installed on the fourth crossbar 17, and the telescopic rod of the second displacement sensor 25 is fixedly connected to the second crossbar 14; a second servo motor 20 is fixedly installed at the bottom of the L-shaped support frame 5, and a second screw 19 is connected to the output shaft of the second servo motor 20; a second threaded sleeve 18 adapted to the second screw 19 is fixedly installed on the fourth crossbar 17; a first spring 21 is installed between the fourth crossbar 17 and the third crossbar 23.

[0014] In use, the substrate or composite sample of the body and coating is placed in the high-temperature fixture 1 (in a preferred embodiment, the testing machine can be set with multiple fixtures to simultaneously test the substrate and the composite). By adjusting the first servo motor 26, the first screw 13 is rotated, which drives the first crossbar 11 to move upward, thereby causing the top rod 4 to move upward and press against the sample 2. During testing, the high-temperature fixture 1 heats the sample 2, causing the sample 2 to expand and drive the top rod 4 to move downward, which in turn drives the third slide rail 9 to move downward. The third slide rail 9 pulls the telescopic rod of the first displacement sensor 6 to generate displacement, which is recorded in the computer. Since the third slide rail 9 moves downward, it will drive the second crossbar 1... 4. The vertical rod 22 and the third horizontal rod 23 move downwards synchronously. The third horizontal rod 23 stretches the first spring 21. The restoring force of the first spring 21 will act on the sample 2 to hinder the expansion of the sample 2. For this reason, a force control structure is set up. When the second horizontal rod 14 moves downwards, it will drive the telescopic rod of the second displacement sensor 25 to move downwards and generate displacement. At this time, by adjusting the second servo motor 20, the second screw 19 is rotated, which drives the fourth horizontal rod 17 to move downwards so that the telescopic rod of the second displacement sensor 25 extends and returns to its initial position. At this time, the first spring 21 also returns to its initial state, canceling the external force interference and preventing the sample 2 from being hindered by expansion.

[0015] In another embodiment, a second spring 24 is provided between the first crossbar 11 and the third crossbar 23, and the second spring 24 provides balance for the first crossbar 11.

[0016] In another embodiment, the top rod 4 is a ceramic rod.

[0017] In another embodiment, the first displacement sensor 6 and the second displacement sensor 25 are both LVDT sensors, which are robust and durable and can achieve frictionless measurement.

[0018] The above description is only a preferred embodiment of the present invention and not all embodiments. Anyone should know that structural changes made under the guidance of the present invention, and any technical solutions that are the same as or similar to the present invention, are within the protection scope of the present invention.

Claims

1. A high-throughput coating thermal expansion coefficient and residual stress tester, characterized in that, The system includes a computer and a testing machine electrically connected to the computer. The testing machine includes a body, with a high-temperature fixture for placing samples mounted on the top of the body. An L-shaped support frame is installed inside the body. A first slide rail and a second slide rail are vertically arranged from top to bottom on one side of the L-shaped support frame. A first slider is slidably mounted on the first slide rail, and a third slide rail is fixedly mounted on the first slider. A third slider is slidably mounted on the third slide rail, and a first crossbar is fixedly mounted on the third slider. A top rod is connected to the first crossbar, extending into the high-temperature fixture and abutting against the sample. A second crossbar is fixedly connected to the bottom of the third slide rail, and a first servo motor is mounted on the second crossbar. A first screw is connected to the output shaft of the first servo motor, and a first screw is fixedly mounted on the first crossbar. A first threaded sleeve adapted to the first screw; a vertical rod is fixedly connected to the bottom of the second crossbar, and a third crossbar is fixedly connected to the bottom of the vertical rod; a first displacement sensor is provided on the top of the inner side of the machine body, and the telescopic rod of the first displacement sensor is fixedly connected to the top of the third slide rail; a second slider is slidably arranged on the second slide rail, a fourth crossbar is fixedly arranged on the second slider, a second displacement sensor is fixedly arranged on the fourth crossbar, and the telescopic rod of the second displacement sensor is fixedly connected to the second crossbar; a second servo motor is fixedly arranged at the bottom of the L-shaped support frame, a second screw is connected to the output shaft of the second servo motor, and a second threaded sleeve adapted to the second screw is fixedly arranged on the fourth crossbar; a first spring is provided between the fourth crossbar and the third crossbar.

2. The high-throughput coating thermal expansion coefficient and residual stress tester as described in claim 1, characterized in that, A second spring is provided between the first crossbar and the third crossbar.

3. The high-throughput coating thermal expansion coefficient and residual stress tester as described in claim 1, characterized in that, The top rod is a ceramic rod.

4. The high-throughput coating thermal expansion coefficient and residual stress tester as described in claim 1, characterized in that, Both the first displacement sensor and the second displacement sensor are LVDT sensors.

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