The development process of the concept of Thermal Shock Tester
The impact test has been developed since 1905 and has become an indispensable inspection item for material properties. The initial test methods are varied, but with the development of the times: the Charpy impact impact test, the Charpy V-type impact Test and Charpy Meeth impact test attention. Before 1968, the United States used a Charpy lock impact test method, but this test method has a drawback: because the lock gap is too blunt, thus to determine the brittle transition temperature is lower than the structure of the brittle fracture temperature, so 68 years later , In the ASTM specification to switch to the use of standard Charpy V-type sample, so the use of V-type and Meishi impact test more. In general, Europe and the United States with Chibi V-type gap more, while Russia is used Chibi Meishi samples.
China's impact test, before the liberation of almost no liberation after a comprehensive study of the Soviet Union, until 1963 only appeared in the first impact test standard GB229-1963, we are now using the latest standard is GB / T229-2007 "metal material Chabi Pendulum test method ", this standard also applies to American standard and European standard. The principle of Thermal Shock Tester is the law of energy conservation, according to the pendulum to interrupt the impact of the number of samples after the impact of the impact of the calculation of work. But this test method is inherently a shortcoming, not as a tensile test machine as a direct display of the curve and the displacement, because we measured the results can only be the impact of power, the impact of energy is energy units, his unit is Joule, The formula for energy is:
W = FS is the impact of power = force * displacement, so these two variables regardless of which changes are caused by the impact of changes in the impact, especially the displacement. So the impact of this value can not directly explain the toughness of the material, can not describe the material in the process of striking changes, only as a reference. In order to solve this problem, people invented the instrumentation impact test method.
Thermal Shock Tester through the high-speed load measurement sensor to generate the signal, amplified by the high-speed amplifier, the A / D quickly converted into a digital signal to the computer for data processing, and by detecting the angular displacement signal to the computer for data processing, high accuracy The Installation of high-speed angular displacement monitoring system and force detection sensors and amplifiers, the computer high-speed sampling, data processing, can display NT and JT curve, data storage, data reporting, etc., can instantly determine and record the material in the impact of the characteristics of the process Curve, by replacing the pendulum and the sample base, can achieve simple beam and cantilever beam two forms of test.
Thermal Shock Tester is divided into high temperature zone, low temperature area, test area three parts, each box of the body of a unique heat structure. Impact mode Application of air way to switch the temperature into the test area, do hot and cold impact test. High temperature impact or low temperature impact, the maximum time up to 9999 minutes, the maximum cycle up to 9999 times. The system can be used for automatic cycle impact or manual selective impact and can be set to two or three areas of the impact of cold and hot start. Cooling mining binary refrigeration system, cooling effect quickly, cooling method for the air-cooled or water-cooled two. Can be connected to the computer, the recorder is only optional. The use of color in English LCD touch control operation interface, easy to operate. In order to ensure that machinery and equipment are often in a good state of technology, ready to run, reduce the downtime, improve the mechanical integrity rate, utilization, reduce mechanical wear, extend mechanical life, reduce mechanical operation and maintenance costs, to ensure safe production, must Strengthen the Thermal Shock Tester maintenance work