The impact test is the most commonly used metallurgical performance test of forged parts. It is used to analyze the work hardening level, the distribution and shape of the residual austenite grains, the amount and characteristics of the retained austenite, and the mechanical properties of the microstructure of the residual austenite, etc. This paper will analyze and discuss the impact test of forgings.
The impact method is to use the instrument to perform a standard impact to a specified surface of the sample or sample, and then measure the energy value or the products formed by both impact methods. The impact of the test method can be divided into two kinds: the charpy impact test, that is, the impact bending test, and the Izod impact test, which is the impact tensile splitting test. According to different energy values, the energy range of the impact test machine used for the impact test of the forgings is generally 30-150 j.
The impact test of the forgings is carried out under the condition of high strain, large deformation and low temperature. The change of mechanical properties caused by plastic deformation provides reference for the improvement of the design parameters of the forming process and the selection of materials to ensure that the forgings with required mechanical properties are obtained.
The impact test of the forgings is used to evaluate the impact toughness of the forgings. Impact toughness is an important indicator to measure the safety of the forgings. A certain impact toughness is required to ensure that the forgings can withstand the external impact or influence, and will not cause the components to break or crack. Therefore, it is also necessary to test the impact toughness of the forgings in production.
The impact test of forgings can be carried out directly on the forgings. The energy value measured in the test can reflect the performance of the forgings. Generally, a higher energy value indicates higher fracture toughness of the forgings and a better impact performance. It is important to note that the sample preparation process before the impact test of forgings will have a great influence on the results of the test. For example, before the impact test of forgings, some scale or debris on the surface of the forgings should be cleaned up to ensure the accuracy of the results.
The impact test of forgings is used to observe and analyze the distribution and shape of the residual austenite grains after plastic deformation, the amount and characteristics of the retained austenite, and the mechanical properties of the microstructure of the residual austenite. It is a special test method of the forgings and has important application value. The test results can provide a theoretical basis for the development of new forging technology and the application of forgings.
In the impact test of forgings, different test pieces need to be operated according to different conditions and different impact energies. For example, when testing the impact toughness of a workpiece, the sample surface should be smooth, no pits and scratches, and the sample preparation process must be strict. The impact test of the forgings should also be corrected to avoid the total energy value being too large or too small due to the error of the impact test instrument or the improper operation of the impact test personnel, so as to ensure that the test results are accurate and reliable.
In conclusion, the impact test of forgings is an important performance test method. It has the advantages of simplicity of operation and time saving, and has important application value in the selection of materials, design of the forging process, evaluation of mechanical properties and other aspects.
