Steels

Steels

1. alloy of iron and carbon

   • less than 2% carbon

2. plain carbon steels

   • low
     • car bodies
     • nails screws chains
     • <0.25% carbon
   • medium
     • shafts
     • gears
     • 0.3 - 0.7 % carbon
   • high
     • springs
     • drills
     • cutting tools
     • > 0.8% carbon

3. alloy elements added to steel

   • to increase strengh
   • improve corrosion resistance
   • high speed tools contain tungsten and chromium
     • strong and stable
   • alloys retain their hardness at high temp

4. maraging steels

   • very high strengh
   • contain nickel cobalt and other elements
   • expensive
   • aircraft under carage