4130 Steel Buildup
4130 Steel Buildup
(OP)
Hello All,
I'm having a problem with some 4130 steel accumulating on a high-carbon, high-chrome, high-nickel (don't know exact concentration) stainless steel guide foot during rolling. The stainless steel is at about 300 F (due to ambient temperature) and the 4130 steel is at about 2250 F. The whole system is being sprayed with water. Not sure why this buildup happens with the 4130, as it doesn't happen with any other compositions.
Any help with possible reasons why this is happening or possible explanations for the problem would be really appreciated.
I'm having a problem with some 4130 steel accumulating on a high-carbon, high-chrome, high-nickel (don't know exact concentration) stainless steel guide foot during rolling. The stainless steel is at about 300 F (due to ambient temperature) and the 4130 steel is at about 2250 F. The whole system is being sprayed with water. Not sure why this buildup happens with the 4130, as it doesn't happen with any other compositions.
Any help with possible reasons why this is happening or possible explanations for the problem would be really appreciated.





RE: 4130 Steel Buildup
RE: 4130 Steel Buildup
RE: 4130 Steel Buildup
For carbon and low alloy steel grades, exposure to air at metal temperatures in excess of even 1600 deg F will result in surface oxidation. Throw in water spray and surface oxides can spall or peel from the hot metal surface. Now you roll this metal oxide layer on a cooler substrate metal surface and it becomes enbedded.
RE: 4130 Steel Buildup
However, x-ray compositional analysis of the buildup on several of the feet after use reveals that the buildup contains much more 4130 steel than oxide, so there's something more going on than just oxidation being removed from the surface, as the oxidized layer would have to be pulling quite a bit of the steel with it as it was being peeled from the surface.
RE: 4130 Steel Buildup
Is 4130 more or less scaley coming out of the furnace than the other alloys you process? Are you seeing any un-oxidized 4130 debris in the build-up? Sounds like there is still a lot of info that needs to be obtained.
Metalhead
RE: 4130 Steel Buildup
I'm really just looking for a direction to head with my research on this issue if there's anything you can think of off the top of your head.
RE: 4130 Steel Buildup
Is there a difference in the temperatures used for the different alloys?
is there a difference in the sizes processed?
rp
RE: 4130 Steel Buildup
RE: 4130 Steel Buildup
Minimize the soak time and suffer the unavoidable consequences of heating alloy steels to high temperatures. In fact, 2250 is way too high for alloy steel hot rolling. Are you letting the operators decide the process? It would appear so. They will always overheat to get more tons through with minimum mill loads. Time to retake control.
Michael McGuire
http://stainlesssteelforengineers.blogspot.com/