Full Transcript:

What’s up guys? This is Michael with Michael Talks Metal back for more metal machinations and that my friends is alliteration. However, we’re here to talk metal, not grammar. Thanks for watching and if you haven’t yet, please subscribe. We’re at a 91% ratio of viewers who aren’t subscribed to those that are! Thanks to those of you who see this and subscribe and thanks for all my subs out there currently! Let’s do this!

Our topic for today is another precipitation hardening type of stainless steel AM 355 or alloy 355 in more generic terms.

The UNS designation for the chemical composition is UNS S35500 and the AISI alloy number is 634.

Capable of high strength after heat treatment and with  corrosion and oxidation resistance , AM 355 finds applications in aircraft or turbine components requiring heat and oxidation resistance at temperatures up to 1000 deg F.

As in all of the precipitation hardening stainless grades, it receives a solution anneal that is followed by a somewhat complex hardening treatment to develop final properties. Cold work can also factor into final properties. Details of these heat treatments are beyond the scope of this video but are often contained in the material specification and much or all of the heat treatment is performed by the producing mill.

Solution anneal at 1900 deg F

Both AMS 5547 and  AMS 5549 specify this condition.

Hardening requires conditioning at 1750 deg followed by  either:

a subzero cooling and temper, the condition required by AMS 5744

or…….. an equalizing and over-tempering treatment , the AMS 5743 condition

or …….. a double ageing treatment

Wow, I need to take a breath after all that.

Details of these heat treatments are beyond the scope of this video but are often contained in the material specification and much or all of the heat treatment is performed by the producing mill.

Chemical Composition    UNS S35500

Carbon ………………………………………..  0.10 – 0.15 %

Manganese …………………………………..  0.50 – 1.25 %

Silicon ………………………………………….. 0.50 % Max

Phosphorus …………………………………..  0.040 % Max

Sulfur ……………………………………………. 0.030 % Max

Chromium ……………………………………… 15.00 – 16.00 %

Nickel ……………………………………………. 4.00 – 5.00 %

Molybdenum ………………………………….. 2.50 – 3.25 %

Nitrogen ………………………………………… 0.07 – 0.13 %

Iron …………………………………………………  Balance

Density  .286 lbs per cubic inch in the solution annealed condition

Minimum  Mechanical Properties:   AMS 5744  –  Longitudinal

170,000 psi Tensile Strength

155,000 psi  Yield  Strength

12 % Elongation

25 % Reduction of Area

Specifications:

Bar and Forgings:

AMS 5743

AMS 5744

Plate:

AMS 5549

Sheet and Strip

AMS 5547

But as we have told our viewers many times before, specifications and part requirements can add to or alter the information we have presented to you today….

So for time 54 – CHECK THE SPECS. Thank you for watching and if you made it this far and haven’t subscribed, click here. Missed previous videos click here. Appreciate you tuning in and see you next Thursday 10am, lastly, go check out our website at michlinmetals.com. See you next week, I’m out!