Magneto Rheological Device MRD180/1T Option 1: Direct flux density measurement Option 2: True temperature measurement Option 3: Double gap system

2 MRD180/1T The new Magneto Rheological Device MRD180/1T consists of:  Temperature controlled joke and bottom plate  Plate PP20  Slot for Hall sensor (ready for direct measurement of the magentic field)  Power supply controlled by software Temperature controlled joke Plate for magnetic fluxdensity measurements Hall sensor slot Coils MRF- Magneto Rheological Fluid Temperature controlled bottom plate

3 Features and Benefit of MRD180/1T  Application of a magnetic field during a rheological test  Magnetic flux density controllable via software  Reading of the set values and analysis of the actual magnetic field in the software after the test (no direct magnetic field measurement)  Software controlled demagnetization  Fluid circulator temperature control to remove the heat produced by the coils and to control the sample temperature  Convenient handling  Ready for magenetic field measurement option  Ready for double gap measurement option

4 Option 1: Direct Magnetic Field Measurements Tesla Meter Zero Gauss Chamber Hall Sensor Analog Output to MCR  Integration of a Hall sensor in the bottom plate of the MRD for online magnetic flux density measurements  Online reading and display of the real actual values in the software

5 Features and Benefits Option 1: Direct Magnetic Field Measurement Simulation data provided by Dr. H. M. Laun et al. BASF Ludwigshafen, 2006  True Flux density measurement  No calibration or analysis required due to changing permeability. The flux density is measured.  Sample permeability can be calculated for different flux densities  Magnetic field along the plate radius measurable (proof of simulations)  Monitoring of MRF switching times

6 Example Option 1: Switching times in MRF Short switching times are required in MRF application Switching on and off of the magnetic field (torque in blue, magnetic flux density in red). Unfiltered raw data sampling of the MCR rheometer (sampling rate 0.1 ms, special firmware) in combination with direct magnetic flux density measurements (option 1) enable the monitoring of switching times. Delay times: switch on: 2.8 ms switch off: 1.8 ms Example data provided by Dr. H. M. Laun et al. BASF Ludwigshafen

7 Option 2: True temperature measurement The magnetic field is produced by a flowing current in the coils. Therefore the coils heat up so that the temperature needs to be controlled by a fluid circulator. The occuring sample temperature is therefore influenced by the heat transferred from the coils to the circulating liquid and should be measured as close as possible to the sample. The „true temperature option“ enables the accurate measurement of the sample temperature with an external temperature sensor in the MRD.

8 Plate for magnetic flux density measurements Hall sensor slot Temperature controlled joke Coils MRF Temperature controlled bottom plate Option 3: Double Gap Measuring System  Double gap measuring system (DG 16) for shear rates up to /s  DG 16 is made of iron  Homogenous magnetic field up to 1.2 T  Direct flux density measurement possible as well

9 Features and Benefits Option 3: Double Gap Measuring System  Shear rate range increased from 0.3 to /s  No gap draining of the sample  Magnetic flux densities up to 1.2 Tesla due the magnetic rotor  Measurement of true flux densities using the Hall sensor  Double gap system patented by BASF and licensed exclusively to Anton Paar

10 Example Option 3: Double gap measuring system Shear rate [1/s] Shear stress [kPa] End of PP 20 shear rate regime MRF measured in at magnetic flux densities from 0 to 1 Tesla.