Most motors are rated by holding torque lb-in / in -lb or Nm. So 16kgf.cm dosen't relate well in my mind offhand.
150 MPA ?
How much HP is required to machine a material can be calculated ( value calculated is not exact ) and depends on spindle speed, feedrate ,depth of cut and machinability of the material. The mechanical aspects of the axis also plays into the above.
Then you also have the characteristics of the material due to machining ie; some may work harden.
Nothing beats some experience so just try cutting some similar material and see what it can do.
RICH