Общий каталог Sumitomo 2018 - 2019 - страница 572

SUMIBORON Technical Guidance Hardened Steel Machining Application Map of the Various Tool Materials Work Materials and Cutting Speed Recommendations Cutting speed (m/min) Heavy Interrupted cutting Coated carbide Cermet SUMIBORON Light Continuous Ceramic Hardened steel Bearing steel Die steel cutting 40 45 50 55 60 65 Notch wear Wear is quite large. Large wear Workpiece hardness (HRC) occurs easily Influence of Coolant on Tool Life Relation Workpiece Hardness and Cutting Forces Continuous cutting Interrupted cutting 0,3 Work material: X155CrVMo12-1 Dry F1 Principal force Flank wear width VB (mm) Non water soluble Cutting data: vc = 100 m/min 150 F2 0,25 F2 Feed force Water emulsion doc = 0,2 mm Water soluble f = 0,1 mm/rev F3 Back force 0,2 Cutting force (N) F3 0,15 100 F1 Tool life 0,1 In continuous cutting of bearing steel, there is 0,05 not much difference in dry or wet cut. 50 Work material: C105W1 Dry Wet Cutting data: vc = 120 m/min 0 20 40 60 80 100 120 140 doc = 0,2 mm Cutting time (min) f = 0,1 mm/rev 0 10 30 50 70 Work material: 100Cr6 (HRC58~62) For continuous cutting, the influence of Workpiece hardness (HRC) Insert: TPGN160304 coolant on tool life is minimal. However for Cutting data: vc = 100 m/min interrupted cutting, coolant will shorten the doc = 0,15 mm tool life because of thermal cracking. Back force increases substantially for harder work materials. f = 0,1 mm/rev Relation between Flank Wear and Cutting Force Workpiece Hardness on Cutting Force and Accuracy Back force (N) 300 Cutting data: vc = 120 m/min Hard Soft Hard doc = 0,5 mm 34CrMo4 Cutting data: vc = 80 m/min HRC65 doc = 0,15 mm zone zone zone f = 0,3 mm/rev 200 dry f = 0,1 mm/rev C55 Shore hardness (HS) 100 HRC24 70 50 45(HS) 0 30 0,05 0,10 Principal force (N) 100 Back force (N) 400 For hardened steel machining, 300 External dimension at the soft 0 back force increases substantially 106N zone is smaller due to lower 200 Feed force (N) 0,05 0,10 due to the expansion of flank wear. cutting forces. 100 Dimension (mm) 0 -10 0 0,05 0,10 -20 Flank wear width VB (mm) Relation Cutting Speed and Surface Roughness Improvement of Surface Roughness by Altering the Feedrate Work material: Constant Feedrate Variable Feedrate 25CrMo4 Surface roughness Ra (μm) BN250 Vc=120 BN250 Vc=150 Previous edge position f 0,3 BN250 Vc=180 (HRC58~62) Holder: MTXNR2525 Insert: TNMA160408NU 0,2 Cutting data: vc= 120, 150, 0,1 180 m/min Stationary notch location Shifting notch location doc = 0,15 mm Technical f = 0,045 mm/rev Guidance 0 0 40 80 120 160 Wet Machining output (pcs.) At high cutting speeds, surface roughness is more stable. Varying the feedrate spreads the notch location over a larger area, surface finish improves and notch wear decreases. N17