Effect of Sulfur content in AISI 4150
Effect of Sulfur content in AISI 4150
(OP)
Hello,
Can someone tell me what effect a higher Sulfur content would do to the fatigue properties of AISI 4150. Our current standard is .015 - .040 % and the proposed material is .064%
Thanks!
Can someone tell me what effect a higher Sulfur content would do to the fatigue properties of AISI 4150. Our current standard is .015 - .040 % and the proposed material is .064%
Thanks!





RE: Effect of Sulfur content in AISI 4150
Increased sulfur will lower fatigue life by increasing the MnS inclusion density. These inclusions act as crack initiation sites in testing the same way that they do for increasing machinability. However, changing from 0.04 to 0.06% is not going to have such a noticable as would be seen with an already low-sulfur steel (say 0.005, etc.).
RE: Effect of Sulfur content in AISI 4150
RE: Effect of Sulfur content in AISI 4150
RE: Effect of Sulfur content in AISI 4150
Changing from 0.020% S to 0.064% S can seriously affect fatigue life by providing initiating sites at the threads and undercut areas, particularly if the shaft is under a bending load. Depending on the actual geometry and loading conditions, it may not matter, but it could.
The Ca-treatment can reduce the life of the bearing surfaces. It is my understanding that Calcium is detrimental to rolling contact fatigue. I would explore other ways to save money.
rp
RE: Effect of Sulfur content in AISI 4150
RE: Effect of Sulfur content in AISI 4150
RE: Effect of Sulfur content in AISI 4150
From your last post, it appears that you are purchasing "Out of Spec" material at a discount price. Beware that the high S is the only thing wrong. I would be concerned with laminated plate (if plate is product) or pipe if bar stock. You may well be getting a lot less than you think for your "cheap-at-the-moment" price.