Malvern Gemini HRnano Rotational Rheometer

Rheometry Lab (Cenimat) 
Lab responsible: Maria Teresa Cidade
The Bohlin Gemini HRnano Rotational Rheometer is a compact instrument with ‘fluids to solids’ measurements capability. It is optimized for both strain controlled and stress controlled operation. It is a high performance, modular rheometer system that includes a wide range of measurement geometries (cone/plate and parallel plates of different plate and cone radius and cone angle, and concentric cylinders) and accessories (electrorheological cell, high pressure cell and torsion of solids).
Bohlin Gemini HRnano Rotational Rheometer may operate in 4 different kind of modes:
Viscometry measures viscosity as a function of shear stress or shear rate. Measurements include single value of shear rate (or stress), table of shear rates (or stresses), continuous shear rate (or stress) ramp (including yield stress) and complex shear rate (or stress) profile.
Oscillation measures the dynamic viscoelastic properties as a function of frequency. Measurements include single frequency, frequency sweep, amplitude sweep, time sweep and temperature sweep (gradient, step change or profile). Tests can be performed at constant stress or constant strain amplitude (under direct control).
Relaxation measures relaxation modulus as a function of time following a step change in strain. The relaxation spectrum and zero shear viscosity can be determined.
Creep and Creep Recovery measures the creep compliance and recoverable compliance as a function of time. User defined sampling modes can be set. Zero shear viscosity and yield stress can be determined.
Temperature control can be isothermal or follow defined gradients or step changes.

Torque range: 10nNm to 200mNm in controlled stress & rate viscometry;
3nNm to 200mNm in controlled stress & strain oscillation
Torque resolution: Better than 1nNm
Position resolution: 50nrad
Frequency range: 1μHz to 150Hz
Controlled speed range (CR mode): 0.01mrad s-1 to 600rad s-1
Measurable speed range (CS mode): 10nrad s-1 to 600rad s-1
Normal force N1 measurement range: 0.001N to 20N
Step change in strain: <10ms
Temperature range: 5ºC to 180ºC (Peltier); ambient to 350ºC (ETC - Extended Temperature Cell)

High Pressure/High Temperature Cell: 300bar pressure, ambient to 300ºC
Electro-rheology Cell: DC voltage up to c.10kV