First cycle residual strain

We indicated all relative quantities by asterisks. Thus we defined the relative first cycle residual strain, and relative first cycle hysteresis energy dissipation by... 

Fig. 7 a and b. Scheme of the thermomechanical behaviour of a well phase-separated thermoelasto-plastic. Stress-strain (or time) curves. Plots of heat effects versus time. First loading (ABC) and unloading (CD) cycle. Second loading (AC) and unloading (CD) cycle. The yielding point occurs at B. AD indicates the residual deformation after the first cycle. AB on the dQ/dT-time curve is the endo-effect resulting from the initial small-strain deformation AB U9)... 

The maximum mechanical hysteresis and residual strain, which were strongly dependent on the hard block content, occurred during the first cycle and the residual elongations and hysteresis decreased with temperature. 

For new installations the first washing cycles result in the removal of fine sand as well as all the other materials usually undesirable in the filter mass, such as particles of bitumen on the inner surface of the water inlet or other residuals from the crushing or straining devices of the filter media. Consequently, it is normal that at the beginning of operation of a filter sand installation, dark colored deposits appear at the surface of the filter mass. In the long term they have no consequence and disappear after a few... 

The torque-time curve was initially somewhat irregular due to the lateral extrusion of some of the sample material during the first few cycles of anvil oscillation. Data was taken after the torque-time curve had stabilized and approximated a square wave. A typical tracing obtained on PP is shown in Fig. 1. Note that during the experiment the rotation speed was increased about 5 fold with no apparent residual effect on the sample. There was only a small increase in torque associated with the higher strain-rate or sliding speed. This is typical of what has been observed with other polymers studied . 

---