Carbon tool steel U7A/U7, C70U, C70W1, C70W2, 1.1520, 1.1620 according to PN-H-85020, DIN 17350, ISO 4957.
| Standard | Steel Grade | |||||||
|---|---|---|---|---|---|---|---|---|
| Chemical composition % | ||||||||
| C: | Mn: | Si: | P: | S: | Cr: | Ni: | Cu: | |
| PN | N7E | |||||||
| 0.65 - 0.74 | 0.15 - 0.30 | 0.15 - 0.30 | <0.025 | <0.025 | <0.15 | <0.20 | <0.20 | |
| PN | N7 | |||||||
| 0.65 - 0.74 | 0.15 - 0.35 | 0.15 - 0.35 | <0.030 | <0.030 | <0.20 | <0.25 | <0.25 | |
| GOST | U7A - У7А | |||||||
| 0.65 - 0.74 | 0.17 - 0.28 | 0.17 - 0.33 | <0.025 | <0.018 | <0.20 | <0.25 | <0.25 | |
| GOST | U7 - У7 | |||||||
| 0.66 - 0.73 | 0.20 - 0.40 | 0.15 - 0.35 | <0.030 | <0.028 | <0.20 | <0.25 | <0.25 | |
| ISO | C70W1 - C70U - 1.1520 | |||||||
| 0.65 - 0.75 | 0.10 - 0.40 | 0.10 - 0.30 | <0.030 | <0.030 | - | - | - | |
| DIN | C70W2 - 1.1620 | |||||||
| 0.65 - 0.74 | 0.10 - 0.35 | 0.10 - 0.30 | <0.030 | <0.030 | - | - | - | |
C70U, U7A, C70W1, C70W2 - specification and application
Deep and shallow hardening carbon steel with the lowest carbon content of N12E carbon materials. It exhibits high impact strength, shock resistance, and relatively high hardness. If we talk about its drawbacks, it is characterized by low abrasion resistance and low machinability. N7E is used for the production of tools for woodworking, soft stones, cutting boards, small die-cutting dies for hot work, smithery hammers. In some cases it can be used as a substitute for spring steels
Mechanical properties of U7A, C70W1, C70W2
- Softened condition - hardness <187 HB
- Hardened condition - hardness >57 HRC
Heat treatment - processes and temperatures:
- Softening annealing at a temperature of 680 - 710 C
- Relief annealing at a temperature of 600 - 700 C
- Hardening at a temperature of 780 - 820 C
- Tempering at a temperature of 170 - 190 C
In the above mentioned grades the company delivers:
Other substitutes for the N7/N7E grade
N7, N7E, C70KU, C70W1, 1.1520, C70W2, 1.1620, U7, U7A, bars C67S, TC70, S71, S72, SK7, SK65, C70E2U, У7, У7А