Alloy SGS-30-55
Descriptions
SGS-30-55 nickel-based superalloy has excellent high temperature properties: creep strength, oxidation and corrosion resistance. It is used for industries of material processing (hot working HF & SPF and glass industry), in aggressive environment, under high temperature and high mechanical stress.
Designations
Designation SEVA : SGS-30-55
Standard designation:
EN Equivalent: GX70NiCrW55-30-7.
Chemical Analysis
Ni : Bal
Cr : 30
W : 7
C : 0.7
Mechanical properties
Hardness: 240 – 300 HB
Tensile test:
300°C | 600°C | 750°C | 900°C | 1000°C | 1050°C | |
Rm(Mpa) | 420 | 400 | 350 | 230 | 155 | 125 |
Rp0,2 (Mpa) | 320 | 300 | 200 | 180 | 120 | 100 |
Young’s modulus at 20°C : E = 170 GPa
Tensile test at room temperature:
Rp0,2 (MPa) | Rm (MPa) | A (%) |
340 | 520 | 2 |
Creep resistance
Creep resistance between 600°C and 1 050°C
600°C | 700°C | 1000°C | 1050°C | |
Stress (MPa) | 250 | 150 | 35 | 35 |
Time to rupture (h) | 378 | 339 | 378 | 100 |
A (%) | 3,6 | 6,3 | 5 | - |
Applications
Areas of use
• Glass industry
• Aircraft industry
• Heat treatment furnace
• Cement works
• Petrochemical industry
• Miscellaneous toolings
Maximum temperature of use
1200°C
Types of parts produced
- Glass toolings
- Toolings for the aircraft industry: Titanium sheets
- Super-Plasic Forming (SPF)
Standard structure
Austenitic, nickel-based matrix with a network of tungsten and chromium carbides.
Physical Properties
Density at 20°C: 7,8
Approximate melting range: 1310 - 1370°C
Expansion coefficient α in 10-6 /°C
Temperature (°C) | α (10-6/°C) |
300 | 12,9 |
400 | 13,7 |
500 | 14 |
600 | 14,6 |
700 | 15,2 |
800 | 15,7 |
900 | 16,1 |
1000 | 16,4 |
Other properties
Thermal conductivity λ in W.K-1.m-1 and thermal mass capacity Cp in J.g-1.°C-1 at various temperatures:
Amb. | 202°C | 402°C | 602°C | 802°C | |
λ | 5,91 | 12,19 | 15,43 | 21,22 | 24,91 |
Cp | 0,489 | 0,509 | 0,603 | 0,672 |
900 | 1002°C | 1172°C | |
λ | 22,65 | 28,74 | 1172°C |
Cp | 0,706 | 0,834 |
Production
SEVA produces the SGS-30-55 alloy in an electric induction furnace, under an argon gas protective atmosphere.
Cast in a sand mold.
Temperature (°C) α Heat treatment: Mechanical reinforcement.
Compatible processes
Compatibility | Remarks | |
Machining | ●●●○○ | Cutting speed recommended: ~ 30 to 50 m/min |
Polishing | ●●●○○ | |
Hot isostatic pressing (HIP) | ●●●●● | |
Forging | ●●●●○ | |
Welding | ●●○○○ | Electrode or TIG. |