Full-Field Temperature and Strain Measurement in Dynamic Tension Tests on SS 304

Abstract

The thermomechanical response of 304-stainless steel tension specimens to a range of strain rates from 7 × 10−3 s−1 to 2600 s − 1 was investigated. Quasi-static tests (7 × 10−3 to 0.8 s−1) were completed on a hydraulic load frame, intermediate tests (200 s−1) were performed with a modified pressure bar, and high strain rate tests (2600 s−1) on a split Hopkinson pressure bar. Full-field infrared thermography and strain measurements were recorded during each test. Infrared measurements were taken using the Telops FAST-IR 1000 infrared camera at rates up to 30,0000 frames per second. 2D-DIC was used to compute strain from simultaneously recorded visible images taken at rates up to 90,000 frames per second. Max temperatures of 290 °C were recorded in the necking region of a uniaxial specimen at a strain rate of 2600 s−1. These measurements can be used to investigate the transition of isothermal deformation to adiabatic deformation and to determine the portion of plastic work converted to heat at each strain rate.