On Friday, April 14, 2017 at 6:18:05 PM UTC-7, m hammond wrote:
I'm looking to machine a piece of round steel to place a magnet in it and want
the steel magnetic as posible

Do you want it magnetically soft? Hard? Permeable to AC fields?

The use of a piece of steel as a magnetic pole piece means you want low-carbon
steel, fully annealed (don't work the steel after annealing). There's lots of
other magnetic properties for various situations, like grain-oriented silicon
steel for two-dimensional AC magnetic field circuits.