"Stress, kPa" "Strain, %" 0 0 0.1 0.1 0 0.2 0.2 0.3 0 0.4 0 0.5 -0.1 0.6 5 0.7 10 0.8 16 0.9 21 1 28 1.1 32 1.2 40 1.3 44 1.4 46 1.5 48 1.6 49 1.7 50 1.8 51 1.9 51.5 2 50 2.1 45 2.2 35 2.3