Treatment method for preventing fracture melting of tensile sample

Abstract

The invention relates to a treatment method for preventing fracture melting of a tensile sample, in particular to a high-temperature plate and strip tensile test performed on a thermal simulation test machine. The treatment method comprises the following steps: sleeving a thermocouple wire with a quartz tube for protection; arranging a set of fixture at the two ends of the plate and strip tensile sample respectively; starting tension under a protection atmosphere; when a necking part occurs on the sample and a power angle fluctuation range delta is greater than 30 degrees, turning a thermal button off to manually stop a heating loop; meanwhile, manually controlling a stroke to tension the sample until breaking. According to the treatment method, power-off treatment is performed when the sample is fractured, so that the phenomenon that topographic characteristics cannot be observed due to fracture melting of the sample caused by a large amount of Joule heat generated at a high-resistance moment in the case of fracture of the sample is prevented, the situation of frequent fracture melting of the sample under a high-temperature condition in an original test is changed, the test success rate is increased, the test cost is lowered, and operation is easy, convenient and feasible.

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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