Antimony in heat resistant steel castings
Antimony in heat resistant steel castings
(OP)
I want to ask you for your opinions regarding antimony influence to heat resistant steel castings. We found antimony content from 0.05 % to 0.1 % (in extremely cases) in two our materials (1 austenitic, 1 ferritic). Fero-niobium (columbium) is suspected as a source (investigation is still in progress).
How detrimental could be effect of antimony up-to 0.1 % to this kind of steels?
In these two steels we have problems with tensile strength, yield strength and elongation (at 20 deg. C) as well.
How detrimental could be effect of antimony up-to 0.1 % to this kind of steels?
In these two steels we have problems with tensile strength, yield strength and elongation (at 20 deg. C) as well.





RE: Antimony in heat resistant steel castings
If any problems were to occur I would envisage this would be with the ferritic due to embrittlement and subsequent cracking. What grades are they?
RE: Antimony in heat resistant steel castings
Mechanical properties of ferritic casting: Rm 290 MPa (shall be 450 MPa), Rp0,2 unmeasurable (shall be 400 MPa). Elongation unmeasurable (shall be 5 %). The fracture was very brittle.
Grades are special, ferritic is 1.4740 + W + Nb, austenitic is chromium-manganese heat resistant steel.
RE: Antimony in heat resistant steel castings
RE: Antimony in heat resistant steel castings
But, I wonder then the content of Antimony in Ferro Niobium for you to record 0.05-0.1%. As metengr states, I agree, Antimony is not a friendly element.
"Even,if you are a minority of one, truth is the truth."
Mahatma Gandhi.
RE: Antimony in heat resistant steel castings
Do you have a lab with an SEM? If you can determine that the fracture was intergranular, then that would support Sb segregation to grain boundaries.
RE: Antimony in heat resistant steel castings
I suspect that hot properties, and long term properties will both suffer.
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P.E. Metallurgy, Plymouth Tube
RE: Antimony in heat resistant steel castings
@winstonsk: fracture brittle, shiny, sparkle in the light, no necking, SEM in external lab can be carried out for information, but after investigation of antimony sources and their rejection
@ed: no aging and corrosions tests, they are not required by customer standard or customer is doing it by himself
Anyway, this is big issue. As all of you wrote it looks like there will be a lot of troubles during service in VTG.
RE: Antimony in heat resistant steel castings
Regards, Wil Taylor
o Trust - But Verify!
o We believe to be true what we prefer to be true.
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o Unfortunately, in science what You 'believe' is irrelevant. ["Orion"]
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RE: Antimony in heat resistant steel castings
je suis charlie