High Strength Materials Flashcards
Name the two types of high-strength materials
- Intermetallics
- Superalloys
How are superalloys defined?
Alloys which have useful levels of mechanical properties (including good “creep resistance”) above 600-700 degrees celcius
What are the main alloying elements for super alloys?
- Nickel
- Cobalt
- Iron
Name the 4 additional alloying elements in superalloys
Chromium, Aluminium, Titanium, Copper
Name the three types of superalloys
- Nickel based (Ni > 50%)
- Cobalt based (Co > 50%)
- Nickel-Iron based (Ni+Fe > 50%)
Main advantages of superalloys
- High Tensile strength at high temperatures
- High heat, corrosion and oxidation resistance
- High creep resistance
- High fatigue life
3 Main Applications of superalloys
- Nuclear Power Plant
- Aerospace engine parts
- Gas Turbines
What are the 5 types of stainless steels
- Austenitic
- Ferritic
- Martensitic
- Duplex
- Precipitation-Hardening
Name the two elements usually present in Ferritic (Martensitic) stainless steel
Iron and Chromium
Name the three elements usually present in Austenitic Stainless Steels
Iron, Chromium and Nickel
What is the crystal structure and magnetic property of Ferritic stainless steels
BCC and Ferromagnetic
What is the crystal structure and magnetic property of Austenitic stainless steels
FCC and Paramagnetic
Is corrosion resistance higher or lower in ferritic steel compared to austenitic steel
Lower
Is strength (hardness) higher or lower in ferritic steel compared to austenitic steel
Higher
Is cost higher or lower in ferritic steel compared to austenitic steel
Lower
