AISI 1018 and AISI 4130 Temperature range, Tensile and Yield

[Mickey74]

I am trying to find some information for AISI 1018 and AISI 4130 and would really appreciate any help.
I need the temperature range for these materials along with the tensile strength, yield strength and elongation.
I also need to know the tensile strength and yield strength at the maximum temperature.
Any advice would be greatly received.

 

[Screwman1]

Lets see; I would guess that at max temperature (liquidus), both the tensile and yield will be nill.
You need to give us more to work with here. The strength is going to vary with the max applied temperature; you need to give us one fixed and we can work with you, otherwise we have too many unknowns.

 

[Mickey74]

Thanks for replying Screwman1.
I'll try to explain further.
ASME II Part D has a `U' table and a `Y' table which give the stress values for elevated temperatures and an indication as to the maximum recommended temperature along with the minimum temperature. AISI 1018 and AISI 4130 are not listed in this standard. The ASTM A29 specification for these materials also does not have this information.
These values are attained from testing and I don't know if this data is readily available and where I could possibly find it?
I am trying to put together Positive Material Appraisals for these materials to gain PED approval.

 

[mrfailure]

Part of the problem for you is properties vary based on heat treatment. 1018 and 4340 only confer composition requirements and do not in any way imply mechanical properite. You first need to identify the applicable ASME (and co-published ASTM) specification covered under the B&PV code for the appropriate to the product form you wish to use; You can then identify maximum allowable temperature, maximum allowable stress at design temperature, and tensile and yield strengths at design temperature. The Code will not help you on elongation, but you should be able to look up published elongatins once you properly identify the material spec.

 

[stanweld]

Mickey74,
Why do you think that you would be able to compare with ASME II Part D and use the AISI grades indiscriminantly in place of materials defined in II-D or other Codes like B31.3? Having said that, assuming that AISI 1018 is in the hot formed condition, the design allowables for SA-36 would be highly similar to AISI 1018. With regard to AISI 4130, a good approximation of values at temperature to 800 F max. would be found in II-D, Table 4 for B7 bolting. At temps below about 650 F, allowable stresses would be a factor of heat treated condition or cold formed condition.

 

[Mickey74]

Thank you stanweld,
Ideally, I would specify materials defined in II-D but I'm looking at gaining PED approval for existing products which are manufactured in Canada and of which there is a great deal of stock. Many thanks for your advice though, this will help.

 

[mrfailure]

I am not sure I understand: You mean you cannot procure materials certified to conform to ASME or ASTM specs but you can get A29 bar for these compositions that is not certified to meet mechanical properties? If true, you need to make sure certs also show qualification for the structural ASME/ASTM alloy of interest.