80-55-06X Ductile Iron
80-55-06X is a grade of ductile iron available in larger rounds and rectangles. This grade tends to contain more pearlite making the material a good fit in applications where considerations to wear resistance and surface finish are required. The additional pearlite also makes this material responsive to heat treating, like through-hardening and surface hardening. Download the 80-55-06X Product Brief, or X Products for all X grades.
Microstructure
The microstructure consists of Types I & II nodular graphite as defined in ASTM A247. The matrix is ferrite with approximately 5–25% pearlite. The edge or rim will have a higher nodular count and will be mostly ferrite. Chill carbides will be less than 5% in any field at 100x and will be well dispersed.
Center Area
100x, etched in 5% Nital
Edge Area
100x, etched in 5% Nital
Heat Treat Response
Dura-Bar 80-55-06X can be heat treated by conventional methods. Hardening can be accomplished by heating and quenching the material from 1600° F resulting in Rockwell C hardness up to 50 HRC. Induction and flame hardening can be performed but may require an additional pre-heat treatment to accomplish the desired hardness and microstructure.
Stock Sizes
Rounds
Size Range: 25.180" to 26.560"
As-cast round bars are made to clean up at the nominal size. Additional stock is added to allow for out-of-round and normal imperfections in the as-cast surface. Stock allowance is a function of the bar diameter - see Stock Allowances for details. Other finishes available are Centerless Grinding and Centerless Turning, for demanding tolerance applications.
Rectangles/Squares
Size Range Rectangles:14.600" x 24.400"
As-cast rectangles are made to the actual size with no allowance for machine stock added. Rectangles are cast to actual dimension, with clean up stock dependent on the height and width ratio. See Stock Allowances for details. Rectangles can be milled to achieve close tolerance benefits - see Services/Milling for details.
Technical Specifications
Chemical Composition
Magnesium is added as an inoculant to produce nodular graphite. Small amounts of alloying elements are used to stabilize the pearlitic structure.
| Element | Percentage |
|---|---|
| Carbon | 3.20–3.85% |
| Silicon | 2.20–3.10% |
| Manganese | 0.10–0.55% |
| Sulfur | 0.02% Max |
| Phosphorus | 0.08% Max |
Mechanical Properties
Hardness properties listed are minimum and maximum across the bar. For rectangles and squares the hardness properties will depend on minimum and maximum section thickness and will be supplied on request.
| Size Range | BHN | ||
|---|---|---|---|
| Inches | mm | Min | Max |
| 1.000–28.000 | 25–711 | 187 | 255 |
Tensile strength is determined from a longitudinal test specimen taken from mid-radius of the as-cast bar.
| Mechanical Properties | |
|---|---|
| Tensile strength psi (min) | 80,000 |
| Yield strength psi (min) | 55,000 |
| Elongation (min) | 6% |
Typical Applications
Automotive:
Gears
Fluid Power:
Cylinder blocks, Gerotors, Glands, Manifolds, Pistons, Rotors, Valves
Machinery:
Barrell Rollers, Bushings, Chain Sheave Rollers, Chuck Bodies, Die Blocks, Flywheels, Gear Racks, Gears, Housings, Pile Drivers, Press Rams, Pulleys, Rams, Rotary Tables, Tie Rod Nuts
Miscellaneous:
Core Boxes, Dies, Disamatic Pouring Rails, Grinding Rolls, Mill Liners , Pattern Plates, Plunger Pin
Power Transmission:
Gears, Pulleys
Pump and Compressor:
Gears, Housings, Liners, Pistons, Rotary Screws, Rotors
Steel Mill:
Guide Rolls, Pinch Rolls, Runout Table Rolls
Transportation:
Gears, Motorcycle Disk Brake, Pulleys, Rail Spacers