AISI 1144 – Stressproof (A311-B)
STRESSPROOF® is made by a patented process which consists of drawing the bar through a special die under heavy draft, then stress relieving it in a precisely controlled furnace.
When Niagara LaSalle developed STRESSPROOF® in 1938, it changed the economics of part production. For the first time, users could get an improved wearability without case hardening, strength without heat treating, plus excellent machinability and tool life.
STRESSPROOF® is electro-magnetically tested using eddy currents. Other benefits include resistance to fatigue and stress, balanced working and minimum warpage and distortion.
STRESSPROOF® can also be induction hardened, but should be watched for quench cracks.
|Phosphorus (P)||0.040 Max.|
* AISI 1144 heats to be used for STRESSPROOF® are nitrogen treated, and contain nitrogen in quantities normally associated with steel produced by the electric furnace process.