Iron Types

Gray Iron

ClassTensileBHN RangeApplications
2525,000 lbs.170-229Small cylinder blocks and heads, pistons, clutch plates, pump bodies, gear boxes, housings
3030,000 lbs.187-241 Automotive cylinder blocks, heads, liners, fly-wheels, clutch plates, medium duty brake drums
3535,000 lbs.207-255 Truck cylinder blocks and heads, heavy fly-wheels and transmission cases, carriers
4040,000 lbs.217-269 Diesel engine castings, liners, cylinders and pistons and heavy parts in general

We work with experts in heat treating to provide ADI – Austempered Ductile Iron

For our classes of Gray Iron please click here.

Ductile Iron

60-40-18 (Annealed)60,000 lbs.40,000 lbs.18%Pressure castings such as valve and pump bodies
65-45-1265,000 lbs.45,000 lbs.12%Machinery castings subject to shock and fatigue loading
80-55-0680,000 lbs.55,000 lbs. 6%Crankshafts, gears and rollers
100-70-03100,000 lbs. 70,000 lbs.3%High strength gears, automotive and machine components

For our classes of Ductile Iron click here.

All the Gray Iron and Ductile Iron poured by Washburn Iron Works starts from bins of select raw material. We combine three types of post-industry scrap steel – punchings, bushlings, and fabricating scrap – with pig iron and alloys to achieve consistent

iron grades. We work closely with our suppliers so that each load of scrap steel is compatible with our quality standards.

Quality assurance begins from the moment our furnaces are brought up to temperature. The grade and quality of every furnace
batch of Gray Iron or Ductile Iron is checked using an Optical Emission Spectrometer which allows Washburn Iron Works to
adjust the iron mix if necessary before any iron is distributed to the pouring areas. All ladles are poured post innoculant.

Process controls include temperature monitoring, hardness verification (bhn hardness) and chemical spectral analysis. Ductile Iron is checked for nodularity. Test bars for both Gray Iron and Ductile Iron are routinely pulled by several accredited laboratories to verify compliance with ASTM standards. These reports are available to our customers.

Cast or Gray Iron in its conventional form is essentially an iron carbon silicon alloy which consists of flake graphite in a steel-like matrix. Gray Iron is a brittle material having little or no ductility. It is normally soft and machinable with relatively low tensile strengths in the unalloyed form.

Gray Iron is the most commonly used cast iron in the industry. A minimum of alloy and added processes makes Gray Iron a versatile material. Gray Iron is characterized by excellent machinability, high damping capabilities and a low modulus of elasticity.

The Ductile Iron we produce today is a cast material consisting of a
steel matrix populated with spheroidal graphite. Ductile Irons has an amazing range of properties which no other single metal can match.
Ductile Iron possess the excellent castability of Gray Iron combined with much of the strength and ductility of steel.

Ductile Iron has a mix of added alloy resulting in an iron well suited to high wear environment.

Other requirements of Ductile Iron: Chemical composition is subordinate to mechanical properties.