  Shear thickening of particle suspensions is characterized by a transition
between lubricated and frictional contacts between the particles. Using 3D
numerical simulations, we study how the inter-particle friction coefficient
influences the effective macroscopic friction coefficient and hence the
microstructure and rheology of dense shear thickening suspensions. We propose
expressions for effective friction coefficient in terms of distance to jamming
for varying shear stresses and particle friction coefficient values. We find
effective friction coefficient to be rather insensitive to interparticle
friction, which is perhaps surprising but agrees with recent theory and
experiments.
