Ferrous Metals and Alloys: Production, General Properties

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Ferrous Metals and Alloys Production, General
Properties Applications

• Chapter 5

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Ferrous metals and alloys

• Among the most useful of all metals
• Contain iron as their base metal
• Carbon and alloy steels
• Stainless steels
• Tool die steels
• Cast irons
• Cast steels

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Steel (What is the definition?)

• A ferrous alloy, as simple as a mixture of iron
  and carbon, but also containing a number of
  alloying elements to impart various properties

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TABLE 5.1 Applications for Selected Carbon and
Alloy Steels
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Examples of ferrous alloy uses

• Sheet steel for automobiles, appliances,
  containers
• Plates for boilers, ships, bridges
• Structural steel such as I-beams, axles, bar
  products, railroad ties, crankshafts
• Tools, dies and molds
• Rods and wire for fasteners such a s bolts,
  rivets, nuts, and staples
• The average US passenger vehicle contains about
  2700 lb of steel (60 of its weight)

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Designations for steel

• AISI and SAE designate carbon and alloy steels
  using 4 digits.
• The first two digits indicate the alloying
  elements and their percentages
• The last two digits indicate the carbon content
  by weight
• ASTM has another designation system

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UNS (Unified Numbering System) is the present
system

• Letter gives the general class of alloy
• G- ANSI and SAE carbon steels
• J- Cast steels
• K-Miscellaneous steels and ferrous alloys
• S-stainless steels
• T-tool steels
• 5 digit number gives chemical composition

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Carbon Steels

• Classified by their proportion (by weight) of
  carbon content
• Low-carbon steel or mild steel (lt.30 Carbon)
• Medium-carbon steel (0.3ltCarbonlt0.6)
• High-carbon steel(gt0.6 Carbon)
• Resulfurized carbon steels
• Alloy steels steels containing significant
  amounts of alloying elements

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TABLE 5.2 Typical Mechanical Properties of
Selected Carbon and Alloy Steels
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Stainless Steels

• Corrosion resistance
• High strength
• High ductility
• High chromium content
• They are called STAINLESS because, in the
  presence of oxygen (air), they develop a thin,
  hard, adherent film of chromium oxide that
  protects the metal from corrosion.

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TABLE 5.5 Mechanical Properties and Typical
Applications of Selected Annealed Stainless
Steels at Room Temperature
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Tool and Die Steels

• Specially alloyed steels designed for
• High strength
• Impact toughness
• Wear resistance at room elevated temperatures
• Used in forming machining metals

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TABLE 5.6 Basic Types of Tool and Die Steels
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TABLE 5.7 Processing and Service
Characteristics of Common Tool and Die Steels
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TABLE 5.8 Typical Tool and Die Materials for
Metalworking Processes