Online Test System Of Local Mechanical Properties Of Materials

Welding, as a processing technical method, becomes increasingly important and indispensable to modern industry. The micro structures of various sectors at the welding joint are greatly uneven, so there are differences in the mechanical property that they display, which seriously affects the safety of using the whole welding equipment. Therefore, more and more attention has been paid to the tests of the service life and safety of present equipment. Traditional test of partial mechanical property of materials is conducted in laboratories mostly after the test sample has been prepared, which will not only damage the equipment but also has grave effect on the testing accuracy due to the course of processing test sample. What's worse, no on line test of materials can be executed. Therefore, how to examine the local mechanical property of present equipments on line has become the focus of our research.With the combination of computer and measurement instrument technology, the automatic test system developed at the direction that the software replaces pure hardware as computer core, which makes the test system is of advantages of a short development cycle, strong function, better expansibility and low cost so on. Based on the double hole micro cut method, the paper designs the test system overall structure which can test local mechanical properties on line. The paper designed the test system device depending on the tasks the test system tries to complete. Using the LabVIEW software development platform, and combining with USB MPS 010601 data acquisition card, the paper designs and develops test system software. Firstly, according to the demand for this test system, the paper analyzes and discusses the selection of DC motors, sensors and data acquisition card in the test system. The test system is mainly studied and built from two aspects of hardware and software. The hardware platform mainly refers to the development of test system device including the design of swinging rod, screw, couplings and bearing. The software platform mainly refers to the building of test system software, which includes the sensor calibration, data acquisition, filtering, storage and playback, data analysis and report generation parts. Adopting the modularizing design thought, the system is correspondingly subdivided into different child modules. Finally, the paper tests the aluminum and the pipeline steel equipments many times and compares this result with traditional tensile testing result. The result shows the test system can better complete online test of active equipment, and gives the indexes of the evaluating local mechanical performance of the equipment.This automatic testing system constructed by visual instrument technology is able to accomplish the auto test of local mechanical property of equipments, reduce testing cost, improve testing efficiency, enhance the flexibility of the system and facilitate on line auto test of present equipment.