FATIGUE-PROOF is a medium-carbon free-machining steel with higher mechanical properties than its companion product, STRESSPROOF. These properties are produced by a process of drawing steel at elevated temperatures, developed and patented by LaSalle Steel Co. The result is a steel with high tensile strength, uniformity of properties, and excellent machinability.
This product possesses high strength as it is received from the mill, and no subsequent heat treatment is required. The strength is remarkably uniform from the surface to the center of the bar and from end to end. Properties are not adversely affected by exposure to temperatures up to 600°F. Where higher hardness is required, material may be selectively hardened by induction heating. Water quenching will produce Rockwell "C" 60, and oil quenching will yield Rockwell "C" 50-55.
FATIGUE-PROOF has excellent machinability for a material of its strength. In standard practice, it will machine up to 25% faster than annealed alloy steels and up to 75% faster than heat-treated alloy steels. Excellent dimensional stability is maintained. Tool use as well as surface finish is better.

Stock Lengths: 12' Approx.

ASTM A311 Class B

Color Marking: Ends painted Red and White