Ice635: Standard ice I

T = 200 K, P = 100 MPa, s = 31 MPa step (1), to strain 0.30

Legend: Upper graph of each pair is motor speed V (proportional to edot); lower graph is load (in volts). Translate motor V to edot thus: V7=4e-5/s. Load to stress translation is 1.28 MPa/mV, with a ~11 mV zero offset. Horizontal scale is time. 5000≈14 hrs.

 

 
e=0.301 1148 hrs
     
e=0.293 1144 hrs
e=0.293

 

 
e=0.257

1126 hrs. Clearly not: this has now been strain hardening over several percent.
e=0.215

1108 hrs. Apparent steady state?
e=0.168 1051 hrs. Yield phenomenon pretty much gone. Note how much strain is required to do this.
e=0.120

1033 hrs. Yield phenomenon--pronounced strain softening beginning around 2-3% strain.

The jagged bit in the middle of the lower (stress) trace result from the drive motor hitting a resonance near V4.4, which effectively makes it stop. Operator had to override constant stress and impose a too high V for a while.