1 Introduction
2 Phase transformation of metastable austenitic steels and investigated materials
C | Cr | Ni | N | Nb | Mn | Mo | Si | Cu | |
---|---|---|---|---|---|---|---|---|---|
B1 | 0.024 | 17.29 | 9.25 | 0.019 | 0.41 | 1.55 | 0.19 | 0.63 | 0.21 |
B2 | 0.021 | 17.19 | 9.44 | 0.022 | 0.38 | 1.55 | 0.23 | 0.59 | 0.11 |
B3 | 0.014 | 18.31 | 10.06 | 0.025 | 0.38 | 0.65 | 0.06 | 0.47 | 0.15 |
B4 | 0.026 | 17.28 | 9.15 | 0.017 | 0.35 | 1.56 | 0.23 | 0.64 | 0.15 |
B5 | 0.031 | 18.04 | 10.11 | 0.027 | 0.36 | 0.65 | 0.042 | 0.54 | 0.13 |
Ms,Eichelmann in °C | Md30,Angel in °C | Average grain diameter in µm | Content of α′-martensite after workpiece preparation in vol% | Microhardness in HV0.01 | |
---|---|---|---|---|---|
B1 | − 81 | 46 | 17 ± 1.5 | 1 ± 0.2 | 189 ± 13.6 |
B2 | − 87 | 46 | 17 ± 0.1 | 0 ± 0 | 176 ± 8.9 |
B3 | − 133 | 38 | 18 ± 1 | 1.4 ± 0.2 | 177 ± 10.2 |
B4 | − 75 | 47 | 15 ± 0.4 | 0.2 ± 0.2 | 182 ± 15.7 |
B5 | − 158 | 32 | 16 ± 0.9 | 1.3 ± 0.2 | 178 ± 6.9 |
3 Experimental setup
Tool geometry (CNMA 120416 T02020) | |
---|---|
Corner radius: 1.6 mm | Clearance angle: 6° |
Rake angle: − 6° | Tool cutting edge inclination: − 6° |
Chamfer angle: 20° | Projected chamfer width: 0.2 mm |
Coating: multilayer (TiN/TiCN/Al2O3) |
Cutting parameters | |
---|---|
Cutting speed | 30 m/min |
Depth of cut | 0.2 mm |
Feed rate | 0.35 mm/rev |
4 Results
4.1 Thermomechanical load
4.2 Deformation-induced α′-martensite
4.3 Microhardness
Batch | Fitting parameter | Uncertainty | Results | ||||
---|---|---|---|---|---|---|---|
HV00.01 |
a
|
b
| σ (%) | R2 | Increase in hardness (%) | Hardness penetration depth (µm) | |
B1 | 189 | 130 | 40 | 7.18 | 0.94 | 66 | 209 |
B2 | 176 | 151 | 41.5 | 5.08 | 0.98 | 86 | 186 |
B3 | 177 | 134 | 56.5 | 5.74 | 0.94 | 76 | 154 |
B4 | 182 | 111 | 33 | 8.63 | 0.96 | 61 | 199 |
B5 | 178 | 155 | 45 | 3.88 | 0.96 | 87 | 184 |