Definition of Strain Rate
Mathematic Definition
Rough Definition – not accurate due to how to define L0
JLR test example –10 strain rate (as target) In all JLR tests, date in yellow boxes are measured directly -Axial Displacement: cross head movement -Axial Strain: strain measured from strain gauge -Axial Force: measured from load cell mounted on the bottom end Time
Axial Displacement Axial Strain
Axial Force
Sec
mm
N
0.03108724 0.03125 0.031412762 0.031575523 0.031738281 0.031901043 0.032063805 0.032226563 0.032389324 0.032552086 0.032714844 0.032877605 0.033040367 0.033203125 0.033365887 0.033528648 0.033691406 0.033854168 0.03401693
mm/mm 0.018267632 0.020750424 0.022842733 0.026037276 0.031506021 0.039343044 0.048848432 0.05900741 0.069636345 0.081659116 0.0961366 0.11325382 0.13198851 0.15108865 0.17000243 0.18891421 0.20818344 0.22781435 0.2478011
-0.13904959 -0.13900094 -0.13892902 -0.13882883 -0.13869627 -0.13852914 -0.13832693 -0.13809007 -0.13781752 -0.13750821 -0.13716608 -0.13680129 -0.13642316 -0.13603288 -0.13562763 -0.13520944 -0.1347858 -0.13436165 -0.13393448
Eng Strain mm/mm
7.5742359 19.97122 34.887718 52.184269 71.222878 90.449989 107.61268 120.55981 128.36293 132.06245 134.00871 136.14685 139.25072 143.73012 150.95399 163.99083 186.45239 218.90036 256.10992
0 4.865E-05 0.00012057 0.00022076 0.00035332 0.00052045 0.00072266 0.00095952 0.00123207 0.00154138 0.00188351 0.0022483 0.00262643 0.00301671 0.00342196 0.00384015 0.00426379 0.00468794 0.00511511
Eng Stress MPa 0.209100759 0.551342383 0.963139837 1.440643046 1.966238981 2.497038862 2.970846619 3.328276035 3.543695563 3.645827639 3.699557738 3.758585039 3.844273098 3.967935201 4.167363463 4.52726949 5.147362304 6.043148395 7.070386965
True ε mm/mm 0 4.86488E-05 0.000120563 0.000220736 0.000353258 0.000520315 0.000722399 0.00095906 0.001231312 0.001540193 0.001881738 0.002245776 0.002622987 0.003012169 0.003416118 0.003832795 0.004254726 0.004676986 0.005102072