The tensile specimens are machined from sheets according to the dimensions as shown in the diagram below. In addition, specimens along the rolling, transverse and 45o direction are prepared and will be-compared in the flow stress measurement.
1. No machining of surface C
– Roughness of Surface C is same as raw material surface
– Thickness T is same as raw material thickness
2. Surface are connected smoothly at A. (Non step at A)
3. All dimensions are in mm
Instron 4505 mechanical testing machine is used in this tensile testing to determine the flow stress data of the stainless steel materials. The extension speed was set at a constant speed of 5mm/min for all the material used. True strain () and true stress were calculated from the measured values of tensile load and stroke by the following equation: