STRESSPROOF® is made by a patented process which consists of drawing the bar through a special die under heavy draft, then stress relieving it. This severe cold working combined with the stress relieving results in a high strength bar with good stability and exceptional machinability. STRESSPROOF® can often replace heat treated alloy steel for machined parts requiring hardness in the range 23-30 HRC. It can be induction hardened but should be watched for quench cracks because of the high sulfur and manganese content. Welding is not recommended. STRESSPROOF® exceeds ASTM A311, Class B.
FATIGUE-PROOF® is an even higher strength grade made by various combinations of mechanical working and thermal treatments. This high strength bar can eliminate heat treating in the 32-36 HRC range plus the secondary operations associated with heat treating, i.e., cleaning, straightening, re-machining and inspection. All this, in combination with free machining, works to reduce end costs. FATIGUE-PROOF® can be induction hardened using the same precautions as with STRESSPROOF®. Welding is not recommended.
Stressproof and Fatigue-Proof are registered trademarks of Niagara-LaSalle
CHEMICAL COMPOSITION: Heat Analysis - ranges and limits %
| C | Mn | P | S | Si |
|---|---|---|---|---|
| .40/.48 | 1.35/1.65 | .040 max | .24/.33 | .15/.30 |
TYPICAL PROPERTIES: Approximate - not for specification
| Product | Tensile (psi) | Yield (psi) | Elongation | Hardness | Machinability |
|---|---|---|---|---|---|
| Stressproof® | 130,000 (mean) |
100,000 min |
12% (mean) |
- |
83% |
| Fatigue-Proof® | 140,000 (mean) |
125,000 min |
10% (mean) |
280 HB* |
80% |
*In the event of a disagreement between hardness and tensile strength, the tensile strength shall govern.
Shapes and Conditions Available:
 | Stressproof® AS Drawn Rounds through 4-1/2" Diameter
| Stressproof® Ground & Polished Rounds through 4-7/16" Diameter
| Stressproof® As Drawn Hexagon through 2"
| Fatigue-Proof® As Drawn Rounds through 1-3/4" Diameter
| |
