This week our video starts a new series about aircraft alloy steels. For our previous introduction to aircraft alloys … click here ( Videos 18 – 21)
Aircraft Quality (aka AQ) alloy steels differ from Commercial Quality (CQ ) in steps taken in manufacture to minimize inclusions and elements that would be harmful to highly stressed components. Stringent testing requirements assure reliable performance and resistance to fatigue failure. All very important in aerospace applications.
For the most critical applications; Premium Aircraft Quality requirements include multiple melting steps to further reduce any inclusions or contaminants.
We will be taking a deeper dive into the individual alloys and common specs in the weeks to come, so we thought it would be useful to do a quick review of some of the abbreviations that we will be using along the way….
Here goes ….
CEM – Consumable Electrode Melted
CEVM – Consumable Electrode Vacuum Melted
ESR – Electro Slag Remelted
VAR – Vacuum Induction Melted
VIM – Vacuum Induction Melted
VD – Vacuum Degassed
MICRO CLEANLINESS REQUIREMENTS
2300 – AMS 2300 Premium Aircraft Quality Cleanliness
2301 – AMS 2301 Aircraft Quality Cleanliness
2304 – AMS 2304 Special Aircraft Quality Cleanliness
HEAT TREATMENT CONDITION
A – Annealed
N – Normalized
N & T – Normalized and Tempered
SR – Stress Relieved
BHN – Brinnell Hardness Number
Rb – Rockwell B scale
Rc – Rockwell C scale
EQH – End Quench Hardenability
DI – Ideal Diameter
HEAT TREAT RESPONSE
Rc – Hardness
MP – Mechanical Properties
YS – Yield Strength
TS – Tensile Strength
Elong – Elongation
RA – Reduction of Area
PSI – Pounds per square inch
KSI – 1 KSI = 1,000 pounds per square inch
Stay tuned for that deeper dive into the most popular alloys and specifications and above all don’t forget to CHECK THE SPECS. This is Michael with Michael Talks Metal. Thanks for watching, Michlin is a distributor of stainless steel and nickel products, check the website for more info! Made it this far and haven’t subscribed, click here. Missed last week, click here. Thanks for tuning in, see you next Thursday 10am. I’m out!