Study on Stability of Plane Strain stretching Test
김영석Young Suk Kim, 박기철Kee Chul Park
Abstract
Recently the plane strain stretching test called RIST-PSST has been developed as a formability test designed for the sheet material industry. To evaluate the stability of the RIST-PSST against several noise factors such as specimen size, specimen surface condition, test speed and blank holding force, Taguchi`s orthogonalarray experiments for the RIST-PSST were carried out and the result was compared to the case of hemispherical punch stretching test known as the limiting dome height test (LDH test). Results showed that the RIST-PSST was more stable than the LDH test for each noise factor. Moreover specimen surface preparation was very important factor on the LDH but the RIST-PSST was not affected largely by surface state of specimen. Therefore due to its simplicity of the test procedure the RIST-PSST can be used easily as a robust testing method to evaluate the press formability of sheet materials in sheet making plant and also to monitor the incoming material in stamping plant.