| MACHINABILITY RATINGS | 
								
								
									| MATERIAL | 
									SPEED SURFACE FT/MIM | 
									SPEED % OF B1112 | 
								
								
									| AISI B1112 | 
									165 | 
									100 | 
								
								
									| Nitronic 30 Annealed | 
									30 | 
									18 | 
								
								
									| Nitronic 40 Annealed | 
									40 | 
									24 | 
								
								
									| Nitronic 50 Annealed | 
									35 | 
									21 | 
								
								
									| Nitronic 50 Grade A or Level 1 | 
									34 | 
									21 | 
								
								
									| Nitronic 50 Grade B or Level 2 | 
									32 | 
									19 | 
								
								
									| Nitronic 50 Grade C or Level 3 | 
									30 | 
									18 | 
								
								
									| Nitronic 50 Grade D or Level 4 | 
									28 | 
									17 | 
								
								
									| Nitronic 50 Grade E or Level 5 | 
									25 | 
									15 | 
								
								
									| Nitronic 60 Annealed | 
									40 | 
									24 | 
								
								
									| Nitronic 60 Grade A or Level 1 | 
									38 | 
									23 | 
								
								
									| Nitronic 60 Grade B or Level 2 | 
									36 | 
									22 | 
								
								
									| Nitronic 60 Grade C or Level 3 | 
									32 | 
									19 | 
								
								
									| Nitronic 60 Grade D or Level 4 | 
									28 | 
									17 | 
								
								
									| Nitronic 60 Grade E or Level 5 | 
									25 | 
									15 | 
								
								
									| 17-4 PH soln treated | 
									75 | 
									45 | 
								
								
									| 17-4 PH aged | 
									60 | 
									36 | 
								
								
									| 
										These machinability ratios must be recognized as approximate values.
										They are a reasonable guide to relative tool life and lower required for cutting .
										It is obvious, however, that variables of speed , cutting oil , feed and depth of cut
										will significantly affect these ratios.
									 |