Читать книгу The Rheology Handbook - Thomas Mezger - Страница 238

1 Stress phase: step in stress to τ0 = 500 Pa, this stress value is kept constantly for t = 5 min

2 Rest phase: step to τ = 0 Pa, the sample remains unstressed for t = 10 min

Measuring result: Creep curve and creep

recovery curve γ(t), see Figure 6.2

As a test result, the time-dependent deformation function γ(t) is measured. In a diagram, the creep curve and creep recovery curve are displayed showing γ on the y-axis, and time t on the x-axis. Usually, both parameters are presented on a linear scale.

The first part of the curve in the time interval between t0 and t2 is termed creep curve (or deformation curve). The second part between t2 and t4 is referred to as creep recovery curve (or re-formation curve). The re-formation value γe indicates the elastic proportion of the VE behavior of the sample, and the value of the finally remaining deformation γv represents the viscous proportion.