austempered ductile iron (ADI) belongs to structural materials with continuously increasing level of production. Excellent mechanical as well as technological properties together with relatively low price are the reason why Austempered ductile iron (ADI) is rated among perspective construction materials. Austempered ductile iron (ADI) is used in many branches of industry as machinebuilding, civil engineering, transport, military industry, mining etc. It is applied mainly to casting for dynamically loaded components, e.g. gear and traversing heels, crankshafts of cars, vans and trucks, swivel pins, rail brakes, pressure pipes in oil industry etc.
Fuerkai Foundry produces the five most common grades recognized by the American Society of Testing and Materials (ASTM).
|
Ref. Grade # |
ASTM A897 Grade |
Tensile Strength |
Yield Strengths |
Elongation |
Brinell Hardness |
| 1 |
130-90-09 |
130,000 p.s.i. |
90,000 p.s.i. |
9% |
269-341 |
| 2 |
150-110-07 |
150,000 p.s.i. |
110,000 p.s.i |
7% |
302-375 |
|
3 |
175-125-04 |
175,000 p.s.i. |
125,000 p.s.i |
4% |
341-444 |
|
4 |
200-155-02 |
200,000 p.s.i. |
155,000 p.s.i |
2% |
388-477 |
|
5 |
230-185-01 |
230,000 p.s.i. |
185,000 p.s.i |
1% |
402-512 |
*Tensile, Yield and Elongation values are minimums required by ASTM A897 for an independantly cast tensile test bar sample.
Grades 1, 2 and 3
Grades 1, 2 and 3 are typically reseved for applications requiring increased strength and toughness while maintaining a reasonable level of ductility and impact resistance. Commonly employed in fabrication to casting conversion projects, these grades offer mechanical performance that is often comparable to steels, but without the added cost. Machining after heat treat is attainable utilizing proper tool selection.
Desirable properties
Yield strength, toughness and impact resistance comparable to many cast/forged steels
Vibration dampening and heat transfer superior to other ferrous/non-ferrous alloys
Significant weight and cost savings over both aluminum and steel castings/forgings
Increased fracture and fatigue strength
Cost savings over aluminum and steel castings/forgings
Common Applications
Shafts, drive yokes and gears
Clamps and brackets
Linkages
Skid plates
Cams
Grades 4 and 5
Grades 4 and 5 excel in wear and abrasion resistance applications. Typically used in the replacement of hardened steels and white irons, these grades have common uses in the construction and farm equipment industries. However, due to their extreme hardnesses, machining of grades 4 and 5 ADI is usually performed prior to heat treat.
Desirable properties
Superior hardness and wearability over as-cast ferritic and pearlitic ductile irons
Significant cost savings compared to exotic steels
Common Applications
Digger, tillage and auger points
Rollers and wheels
Machine tool components