Cold work tool steel
ALTA S7 Tool Steel Specification
Steel properties
ALTA S7 steel is a shock-resisting tool steel, an air or oil hardening tool steel that is characterized by very high impact toughness. It can be used for both cold and hot work (temperature ≤ 538℃) service, by its good combination of high strength and toughness. The around 3%Cr chromium and high composition Mo% molybdenum allow S7 tool steel have the highest hardenability among those impact resistance tool steel.
** According to the results of TEM and Thermo-Calc, the main carbide types in S7 steel are M3C, M23C6, MC, M6C and M7C3.
Applications
² Making impact-resistant and softening-resistant tools, such as :
-- punches, forging dies, hammers, chisels, clamp dies, cutting tools
² Suitable for hot and cold work impact tools and plastic molds
Chemical composition
Chemical Composition per %
|
C |
Si |
Mn |
P |
S |
Cr |
Mo |
V |
Ni |
Cu |
Min. |
0.45 |
0.20 |
0.20 |
|
|
3.00 |
1.35 |
0.20 |
|
|
Max. |
0.55 |
0.70 |
0.90 |
0.020 |
0.010 |
3.50 |
1.80 |
0.35 |
0.25 |
0.25 |
Basic melting process : |
IM/EAF + LF + VD + (ESR) |
Hardness : |
Max 229 HB (annealed) |
Reduction ratio : |
5 : 1 minimum or required |
Grain size : |
≥ 6.0 per ASTM E112 |
Non-metallic inclusion : |
≤ 1.0 (thick), ≤ 1.5 (thin) per ASTM E45 method A (more pure by ESR route) |
Ultrasonic Test |
SEP1921, , EN 10308, ASTM A388 or agreed methods |
Macro-structure |
As per ASTM E381 |
Straightness / flatness |
≤ 1.5 mm / m (machined), ≤ 2.5 mm / m (black) |
Tolerance |
Per discussed |
Size range (round bars) |
Ø 12 - 500 mm |
Size range (flats, plates) |
12 - 500 mm in thickness max. 1100 mm in width |
Heat treatment
Annealing |
Temperature(°C) |
Hardness |
815 - 845 |
max. 229 HB |
Hot-forming |
Temperature(°C) |
980 - 1120 |
Hardening and tempering |
Quenching temperature(°C) |
Quenching medium |
Frequently-used tempering temperature(°C) |
925 - 955 |
Oil |
200 - 600 |
Ac1 | Ac3 | Ar1 | Ar3 | Ms |
780 | 830 | 715 | 745 | 230 |
** Recommended quenching + tempering processing
1. The high temperature tempering treatment is air quenching at 930~950℃, tempering at 500~580℃, air cooled, hardness value is 48 - 54 HRC.
2. The low temperature tempering treatment is air quenching at 930~950℃, tempering at 180~240℃, air cooled, hardness value is 57 - 61 HRC.
Downloads
-
2024-06-12 Alta S7 SPEC (011 - S6 - T1 ).pdf
끂43 635.85 KB
Features
² High impact toughness
² High strength
² Good wear resistance
² Good heat fatigue resistance
² Good dimensional stability
Copyright © 2024 Alta Special Steel all right reserved
News/Blog
- 2024-09-04
- 2024-08-31
- 2024-07-10
- 2024-06-14