Ductile Iron Castings

Fe Ductile Iron Alloy Castings, Door Hardware Housing, Security/Door/Lock Hardware Industry
Fe Ductile Iron Alloy Castings, Door Hardware Housing, Security/Door/Lock Hardware
Fe Ductile Iron Alloy Castings, Assembly Line Hand Tools Cylinder, Engine Industry
Fe Ductile Iron Alloy Castings, Assembly Line Hand Tools Cylinder, Industrial
Fe Ductile Iron Alloy Castings, Door Hardware Actuating Arm, Security/Door/Lock Hardware Industry
Fe Ductile Iron Alloy Castings, Door Hardware Actuating Arm, Security/Door/Lock Hardware
Fe Ductile Iron Alloy Castings, Door Hardware Housing, Security/Door/Lock Hardware Industry
Fe Ductile Iron Alloy Castings, Door Hardware Housing, Security/Door/Lock Hardware

Ductile iron cast parts have been used in many industries throughout the last several decades contributing to the advancement of man and their machines. Product designer engineers have a tremendous amount of versatility without sacrificing performance when specifying ductile iron for their castings. Ductile iron castings provide the design engineer with the best combination of castability, ability for surface hardening, elasticity modulus, corrosion resistance, strength versus weight ratio, while having a favorable cost of manufacturing. Other ferrous cast materials may be superior in one or two other characteristics and may not be the material of choice in certain situations. However, ductile iron gives the designer more design freedom and provides the best overall combination of cast and post-cast characteristics.

Ductile Iron alloys poured:

  • ASTM A536 Grade 80-55-06 (SAE D5506)
    • Tensile strength of 80 ksi
    • Yield Strength of 55 ksi
    • Ductility (elongation) is 6%
    • Brinell Hardness of 187-255
  • ASTM A536 Grade 60-40-18 (SAE D4018)
    • Tensile strength of 60 ksi
    • Yield Strength of 40 ksi
    • Ductility (elongation) is 18%
    • Brinell Hardness of 187 maximum
    • Nominal machining speed of 100 m/mm with carbide tools
  • ASTM A536 Grade 65-45-12 (SAE D4512)
    • Tensile strength of 65 ksi
    • Yield Strength of 45 ksi
    • Ductility (elongation) is 12%
    • Brinell Hardness of 156-217
  • ASTM A536 Grade 100-70-03 (SAE D7003)
    • High strength alloy with 100 ksi ultimate
    • Yeild Strength of 70 ksi
    • Ductility (elongation) is limited to 3%
    • Brinell Hardness of 214-302
    • Nominal machining speed of 66 m/mm with carbide tools
    • 10 % lighter than carbon steel

In addition to “overall” design freedom, ferrous castings are more cost effective and produce a consistent casting. The reasons being their non-existent shrink rate which does not require addition metal to feed the part in order to counteract the shirk rate of the metal. And with correctly designed castings, this also prevents the formation of external shrinkage (or short cast) defects in the cast part. A testament to this is automobile industry’s wide use of ductile iron in several applications including safety critical components in the steering and braking systems.

Ductile iron offers design flexibility, reduced manufacturing costs versus welded fabrications and forgings, a wide range of “best in class” characteristics, and the confidence of being a widely used ferrous material in several major manufacturing industries from automotive to aerospace as a cost effective alternative to other ferrous alloys.

Austempered Ductile Iron

Austempering is a heat treat process developed to improve the strength and toughness of ferrous alloys like ductile iron.  As-cast ductile iron can be austempered to achieve greater tensile and yield strengths as a secondary service.   Austempering is produced in five (5) different ASTM A897 grades with Grade 1 producing a tensile strength of 130 ksi and a yield of 90 ksi up to a Grade 5 resulting in a tensile of 230 ksi and a yield of 185 ksi.  For Grades 1 -3, secondary machining operations can be performed prior to austempering in most cases.  For Grade 4 and 5, it is recommended the austempering process be preformed prior to any secondary straightening or machining.