I am just experimenting with the FEA simulation software within solidworks. I have just been modelling a tapered shaft and a mating socket, applying a force, and running the software. It all seemed to be working fine, giving expected results, until i started to change the global friction, i would expect as friction was increased the stress in the socket would reduce. However i get the lowest stress at around 0.4 and then it increases up to 1, where i stopped. I cant understand why it is doing this?