Shot Peening Aermet 100

[triumph406]

I work at a facility that makes aerospace test hardware. We have a requirement to make a part from Aermet 100. The part is highly stressed, with a Factor of safety of 3 on UTS. We have been told not to use Vascomax350 as it's too brittle. and have chosen Aermet 100 as an alternate material.

Our customer is asking us to shotpeen the part after final machining. There are no sharp corners on the part, or sharp changes in x-section.

What is the forums experience with shot peening Aermet 100 to increase fatigue life?

Thanks for any help you can give me
Dave

 

[unclesyd]

We have a number of components in a mechanical drive system made from Aermet 100. The components parts that have relative motion between them are shot peened. We have the following combinations Aermet 100/H11, Aermet 100/D2, and Aermet 100/Aermet 100. We were getting a life of about 18 months prior to shot peening one particular component. The first components to shot peened have run almost two years without any reported failure.

If fatigue is a problem I don't think shot peening can hurt.

Here is one article on shoot peening to correct for HT problems.

http://www.shotpeener.com/library/spc/1992026.htm

Here are some good people to contact for additional information.

http://www.metalimprovement.com/metal_fatigue.php

You also may want to contact Cartech.

 

[swall]

Haven't peened any Aermet, but have shot peened Vascomax 350 valve springs. We just ran it through a typical peening cycle used for Cr-Si valve springs.

 

[TVP]

Some additional information on shot peening of maraging steels:

http://www.shotpeening.org/ICSP/icsp-3-76.pdf

http://www.shotpeening.org/ICSP/icsp-4-11.pdf

http://www.shotpeening.org/ICSP/icsp-4-29.pdf

http://www.shotpeening.org/ICSP/icsp-4-30.pdf

 

[yates]

Even without any abrupt changes in section, shot-peening has a beneficial influence on fatigue resistance. We have increased fatigue life (albeit on high load, high amplitude representative fatigue testing for fasteners) of Aermet 100 big-end bolts by shot-peening the relieved shank areas.

 

[triumph406]

Thank you, unclesyd,swall,tvp and yates for your help and time.
This is uncharted teritory for us, at least while I've been here at this company.
Thanks again!