Application of S7:
Because of its unusual combination of properties, S7 tool steel is suitable and versatile for a wide range of tool and die applications. AISI S7 Steel can be used for hot and cold shock applications, medium hot-work dies and medium-run cold work tools and dies. Other uses include: Bull Riveters, Concrete Breakers (Moll Points), Riveting Dies, Powder Metal Dies, Notching Dies, Dowels, Drills, Drill Plates, Hubs, Plastic Mold Dies, Cold Forming Dies, Blanking Dies, Bending Dies, engraving dies, machined cavities for plastic molding dies, die-casting dies, shear blades and Master Hobs. Our special steel offers good price and quality AISI S7 tool steel materials. And we will have S7 steel price promotion sometimes, sign up our price list newsletter to have the latest price of S7 steels.
Introduction of S7:
Shock-resisting tool steels are designated as group S steels according to the AISI classification system. S1, S2, S5, S6, and S7 are the types of shock-resisting tool steels. The hardenability of group S steels can be controlled by varying their composition instead of adjusting the melting procedures and grain size. These steels can obtain optimum hardness at higher austenitizing temperatures. The tempering resistance of group S steels can be enhanced by addition of silicon, which also forms a microstructure to resist distortion in tempered conditions.
Chemical Composition of S7:
Element Content (%)
Iron, Fe 93.85
Carbon, C 0.45-0.55
Manganese, Mn 0.20-0.80
Silicon, Si 0.20-1.00
Chromium, Cr 3.00-3.50
Molybdenum, Mo 1.30-1.80
Vanadium, V 0.20-0.30
Copper, Cu 0.25
Phosphorus, P 0.03
Sulfur, S 0.03
Mechanical Properties of S7:
Properties Metric Imperial
Hardness, Rockwell C (air cooled from 941°C, 649°C temper temperature) 41 41
Hardness, Rockwell C (air cooled from 941°C, 449°C temper temperature) 53 53
Hardness, Rockwell C (air cooled from 941°C, 149°C temper temperature) 57 57
Modulus of elasticity 207 GPA 30000 ksi
Charpy impact (V-notch; air cooled from 941°C; 425°C temper temperature) 13.6 J 10.0 ft-lb
Charpy impact (V-notch; air cooled from 941°C; 649°C temper temperature) 16.3 J 12.0 ft-lb
Charpy impact (V-notch; air cooled from 941°C; 200°C temper temperature) 16.9 J 12.5 ft-lb
Machinability (1% carbon steel) 70.0 - 75.0% 70.0 - 75.0%
Poisson's ratio 0.27-0.30 0.27-0.30
AISI S7 Tool Steel Heat Treatment:
Annealing
Anneal in a protective atmosphere. Heat rapidly to 1500 to 1550°F and hold at that temperature for one and one-half hours for each inch of greatest thickness. To obtain best machining properties, cool slowly to 1000°F, and then air-cool. This annealing procedure should produce a hardness of Brinell 197 max.
Stress Relief S7 steel Material: When desirable to relieve the strains of machining, heat slowly to 1050°-1250°F, allow to equalize, then cool in air.
Hardening
Preheat: Warm steel S7 slightly before charging into the preheat furnace 1200°-1300°F, prior to harden
