To start I would use a 2 flute high speed steel end mill, I don't know what a carbonised cutter is. You will need your work clamped good, no movement. You may need to clamp your work on a soft plate and move your clamps as you cut. If it picks up any you can kiss your mill good by. No slop in your spindle or in your X Y and Z axis. I would use coolant too, air if you don't have coolant. With that said, if your mill is loading up drop your RPM's. Then start dropping your feed till your mill stops breaking. Hope this helps you.