What is ASTM A320?ASTM A320 is a Specification for Alloy-Steel and Stainless Steel Bolting for Low-Temperature Service.
CategoryCorrosion-Resisting and Heat-Resisting Steels
ScopeThis specification covers alloy steel bolting for pressure vessels, valves, flanges, and fittings for low-temperature service.
Ok let's start with ASTM A320 chemical composition.
C0.38 - 0.48
Mn0.75 - 1.00
Si0.15 - 0.35
Cr0.80 - 1.10
Mo0.15 - 0.25
Learn more about chemical composition.
Now it's the mechanical properties turn:
Grade L7105 ksi (725 MPa) min
Learn more about what is yield strength.
Grade L7125 ksi (860 MPa) min
Learn more about what is tensile strength.
Elongation (min.) 50 mm0.16.
Learn more about what is elongation.
Reduction of Area (min. %)0.5.
Learn more about reduction of area.
Grade L7321 HBW or 35 HRC max
Learn more about what is hardness.
Grade L727J minimum
Learn more about impact testing (charpy v notch).
Density7480 - 8000 kg/m3 (around 7.9 g/cm3 or 0.285 lb/in3).
Learn more about density.
Elastic Modulus180 GPa (26107 ksi) - 210GPa (30458 ksi).
Learn more about the Elastic Modulus.
Poisson's RatioUsually around 0.26 – 0.31.
Learn more about the poisson ratio.
Allowable StressDepends on the project (And its factor of safety).
Learn more about the what is allowable stress.
My Material's RankWhile engineers will often look for the cheapest material they can use, I took a different approach to material's selection to help newbie students.
I ranked materials according to their yield strengths and ASTM A320 currently ranks 6 in my yield strength index. This means there are other 5 materials that are more resistant.
Note: I've analysed 134 materials in order to create an yield strength index. Check my astm material's comparison post for more details.
ASTM ClassroomAre you having trouble understanding the basics of ASTM?
What is the difference between Code, Standard & Specification?
This video will walk you through:
CitationWhen you need to include a fact or piece of information in an assignment or essay you should also include where and how you found that piece of information.
That gives credibility to your paper and it is sometimes required in higher education.
To make your life (and citation) easier just copy & paste the information below into your assignment or essay:
Luz, Gelson. ASTM A320 Properties (Chem., Mech. & Rankings). Materials Blog. Gelsonluz.com. dd mmmm. yyyy. <URL>
Now replace dd, mmmm and yyyy with the day, month, and year you browsed this page. Also replace URL for the actual url of this page (The < and > stay, ok?). This citation format is based on MLA.
Other ReferencesA194/A194M Specification for Carbon and Alloy Steel Nuts
for Bolts for High Pressure or High Temperature Service,
A370 Test Methods and Definitions for Mechanical Testing
of Steel Products
A962/A962M Specification for Common Requirements for
Bolting Intended for Use at Any Temperature from Cryogenic
to the Creep Range
E566 Practice for Electromagnetic (Eddy-Current) Sorting
of Ferrous Metals
F436 Specification for Hardened Steel Washers
F606 Test Methods for Determining the Mechanical Properties
of Externally and Internally Threaded Fasteners,
Washers, Direct Tension Indicators, and Rivets