SSDI (Solution Strengthened Ductile Iron)
Dura-Bar SSDI is a grade of ductile iron that combines the elevated mechanical strengths of a pearlitic ductile iron with the machinability advantages of a ferritic ductile iron. By combining the best of both desired properties, Dura-Bar SSDI is an attractive grade of ductile iron that provides several benefits towards designing and manufacturing of metal components. Download the SSDI Product Brief or the SSDI Sales Flyer to learn more.
Microstructure
The microstructure consists of Types I & II nodular graphite. Microstructure attributes can be summarized as 85% nodularity. Pearlite percentage for the center and edge of the bar is 5–30% and 0–15%, respectively.
Center Area
100x, etched in 5% Nital
Edge Area
100x, etched in 5% Nital
Heat Treat Response
Initial test results prove Dura-Bar SSDI can be oil quench hardened from 1650° F (898° C) to a hardness Rockwell C 35–40. From these tests, it can be concluded that there is an overall uniformity and consistency to. When untreated, SSDI’s microstructure is primarily ferritic, however when heat treated, the microstructure changes and becomes martensitic.
Stock Sizes: SSDI
Rounds
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.
| Grade | Shape | Diameter (in) | Surface | Weight (lb/ft) |
|---|
Rectangles
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.
| Grade | Shape | Height (in) | Width (in) | Surface | Weight (lb/ft) |
|---|
Squares
As-cast squares are made to the actual size with no allowance for machine stock added. Squares are cast to actual dimension, with clean up stock dependent on the height and width ratio. See Stock Allowances for details. Squares can be milled to achieve close tolerance benefits — see Services/Milling for details.
| Grade | Shape | Height (in) | Width (in) | Surface | Weight (lb/ft) |
|---|
Custom Shapes
Sizes can be designed to meet your requirements.
All custom shapes are special order and are quoted individually at minimum run quantities. Contact us to find out if a Dura-Bar custom shape will work for your part.
Technical Specifications
Chemical Composition
*Carbon and silicon targets are specified for each bar size in order to maintain mechanical properties. Magnesium is added as an inoculant to produce nodular graphite.
| Element | Percentage |
|---|---|
| Carbon* | 3.20–3.75% |
| Silicon* | 3.25–4.00% |
| Manganese | 0.15–0.35% |
| Sulfur | 0.025% Max |
| Phosphorus | 0.05% Max |
Mechanical Properties
Hardness properties for various diameters are shown in the table. Hardness properties listed are minimum and maximum across the bar. For rectangles, squares and shapes, the hardness properties will depend on minimum and maximum section thickness and will be supplied on request.
| Size Range | BHN | ||
|---|---|---|---|
| Inches | mm | Min | Max |
| 1.000–20.000 | 25–508 | 167 | 229 |
Tensile strength is determined from a longitudinal test specimen take from mid-radius of the as-cast bar.
| Mechanical Properties | |
|---|---|
| Tensile strength psi (min) | 75,000 |
| Yield strength psi (min) | 55,000 |
| Elongation (min) | 15% |
Typical Applications
Fluid Power:
Compressors Rotors, Hydraulic Manifolds & Cylinders.
Oil & Gas:
Plug Value Inserts and Crossheads