Steel 1144 FRP 3

[JSBCintl]

I have a specification for Steel 1144 FRP 280-330 BHN, for use in making a Pinion Blank. Can somebody enlighten me as to the use and properties of this steel.
Any help would be appreciated.
JSBCintl

 

[metman]

This is a medium Carbon, Free Machining Steel (Resulfurized), with Manganese as the primary alloying element.

280 BHN is about 134,000 psi tensile strength.

This is a direct hardening steel as opposed to a carburizing grade. In other words, it has sufficient Carbon to respond to quench and temper without the need for carburizing.

The medium Carbon (.44%) allows for enough surface hardness for reasonable wear resistance at light duty and the Manganese provides for some depth of hardening to support the the sub-surface contact stresses of a gear tooth. The Sulpher creates Sulfide inclusions which act as stress concentrators or initiation points for fatigue failure. However, if the stress is below the endurance limit, the design is viable.

I do not know what the FRP stands for but someone will likely answer this.

 

[ornerynorsk]

I've never seen the term FRP, but 1144 is used as the ingredient in Stress-Proof and Fatigue-Proof steels (Niagara LaSalle), also available under other tradenames, and is well suited to pinions, shafts, gear blanks, etc.

Data here >

http://www.niagaralasalle.com/downloads.html

Good luck.

It is better to have enough ideas for some of them to be wrong, than to be always right by having no ideas at all.