fatigue curve 2219 T852 Kt=1

[kevlar49]

Does anyone know where I can find a fatigue (SN) curve for 2219 T852, at a Kt=1?

 

[jagad5]

If you can obtain a copy of Alcoa Green Letter: Alcoa Aluminum Alloys 2219 and 2419, a brochure published in 1983, there are multiple SN curves, with the data plotted on the graphs.

The typical curve has the following values:
Life Stress (ksi)
10^4 46
10^5 34
10^6 26
10^7 20
10^8 16.5
5x10^8 15

This would be for rotary bending load, R=-1 at room temp.

Also look for Rateick, et.al., Relationship of microstructure to fatigue strength loss in anodised aluminum-copper alloys,
Materials Science and Technology, Volume 21 (2005), No. 10, pp. 1227-1235


Doug

 

[TVP]

Have you checked MIL-HDBK-5J or DOT/FAA/AR/MMPDS-01? I know alloy 2219 is in there, but I don't have my copy immediately handy. There is also quite a bit of information (curves, tables, etc) for 2219 in the ASM publication Fatigue Data Book: Light Structural Alloys. Here is a link to Google Books:

http://books.google.com/books/about/Fatigue_data_book.html?id=RO0XNO753kQC&redir_esc=y

 

[kevlar49]

TVP,

yes. They only contain Kt=2 and up. While using that would be conservative, it is double dipping because we already use peak stress from FEA. Thanks though.

 

[Kwan]

I would use the model stess to develop the Kt. Then use the appropriate SN curve. I think if you factor your stress up for a lower Kt curve you will have incorrect results. You can see this if you find the life using the 3.2 curve (for a given stress)and then factor your stress up (3.2/2.0) and find the life using a 2.0 curve.