SAE 8640 Properties ⚙️ (Chem., Mech. & Rankings) rev. 2022

 

In this post I'll talk about SAE 8640. First let's describe it and then have a look at its material's properties.

What is SAE 8640?

SAE 8640 is a nickel-chromium-molybdenum steel that contains 0.40% carbon, approximately.

Application

They are used in seamless mechanical tubing.

UNS Number

G86400

Ok let's start with SAE 8640 Chemical Composition.

Chemical Composition

C, Carbon

0.38–0.43

Mn, Manganese

0.75–1.00

P, Phosphorus max.

0.040

S, Sulfur max.

0.040

Si, Silicon

0.15–0.35

Ni, Nickel

0.40–0.70

Cr, Chromium

0.40–0.60

Mo, Molybdenum

0.15–0.25

Learn more about Chemical Composition.

Now it's the mechanical properties turn:

Yield Strength

380 MPa

Learn more about Yield Strength.

Tensile Strength

570 MPa

Learn more about Tensile Strength.

Elongation (min.)

0,23.

Learn more about Elongation.

Hardness

Brinell

170

Learn more about Hardness.

Density

7.8 g/cm3.

Learn more about Density.

Elastic Modulus

190 GPa.

Learn more about Elastic Modulus.

Poisson's ratio

0.29.

Learn more about Poisson's ratio.

Allowable Stress or Factor of Safety

Depends on the project (And its factor of safety).

Learn more about Allowable Stress or Factor of Safety.

My Material's Ranking Research

While 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 SAE 8640 currently ranks 62 in my yield strength index. This means there are other 61 materials that are more resistant.

Note: I've analysed 162 materials in order to create an yield strength index. Check my material's comparison post for more details.

SAE Classroom

Are you having trouble understanding the basics of SAE?

What is SAE: Classification and specification?

This video will walk you through:

References

ASTM A519 and other references.

Citation

When 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 and paste the information below into your assignment or essay:

Luz, Gelson. SAE 8640 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. This citation format is based on MLA.

Equivalent Specifications

DIN 1.6546 UNI 40 NiCrMo 2 KB B.S. Type 7 ASTM A322 ASTM A331⁣
ASTM A506 ASTM A519 SAE J404 SAE J412 SAE J770⁣
ASTM A29 ASTM A752 ASTM A829 SAE J1397 MIL SPEC MIL-S-16974⁣