A Treatment Method for Preventing Fracture Melting of Tensile Specimen

Abstract

The invention relates to a treatment method for preventing fracture melting of a tensile sample, in particular to performing a high-temperature strip tensile test on a thermal simulation testing machine. Protect the thermocouple wire sleeve quartz tube, install a set of fixtures at both ends of the strip tensile sample, and start stretching under the protective atmosphere. When the sample appears constricted, and the power angle fluctuation range Δ> 30°, press the thermal button off, manually stop the heating circuit, and at the same time manually control the stroke to stretch the sample, just pull it off. In the present invention, the power-off treatment is performed on the sample when it breaks to prevent the sample fracture from melting due to the large amount of Joule heat generated instantaneously by the large resistance when the sample breaks, so that the morphology characteristics cannot be observed, which changes the original test at high temperature. Under the condition that the sample frequently undergoes fracture melting, the success rate of the test is improved, the test cost is reduced, and the operation is simple and easy.

Description

technical field [0001] The invention relates to a treatment method for preventing fracture melting of a tensile sample, in particular to performing a high-temperature strip tensile test on a thermal simulation testing machine, and belongs to the field of thermal / mechanical simulation physics experiments. Background technique [0002] Gleeble1500D thermal simulation testing machine is a resistance heating full simulation device that can precisely control temperature, stress and strain parameters at the same time. The existing thermal stretching system can only be used for the stretching of rods, and does not have the function of tensile testing of metal material strips, and the research of strip stretching is very important for the research of other metal materials such as steel. The thermoplasticity, hot strength, hot stamping performance and various heat treatment properties of strip steel are the important contents of strip material research; in the utility model patent of...

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Problems solved by technology

The existing thermal stretching system can only be used for the stretching of rods, and does not have the function of tensile testing of metal material strips, and the research of strip stretching is very important for the research of other metal materials such as steel. The thermoplasticity, hot strength, hot stamping performance and various heat treatment properties of strip steel are the important contents of strip material research; in the utility model patent of application number 201020227042.6 "a strip hot tensile fixture on a thermal simulation testing machine", The designed fixture system can only be suitable for single-thickness strip, which has more restrictions on the sample. At the same time, there is melting in the tensile fracture of the strip, so the fracture morphology cannot be observed, and an important experimental data is lost; the application number is: In the utility model patent of 201120448070.7 "A Strip Tensile Clamping Structure for Thermal Simulator", the designed pin hole can improve the clamping force, but the design of the pin hole virtually fixes the thickness of the strip , the sample is single, and at the same time, there is also the case of fracture melting

The tensile test is often carried out under high temperature conditions. Under high temperature conditions, at the moment when the stretching neck is broken, due to the instantaneous increase in resistance, the current has not had time to decrease accordingly, so a large amount of heat is generated, causing the port to melt. , it is impossible to observe the shape of the port, which leads to the failure of the test and greatly increases the cost of the test

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