fatigue test

[nadim22]

Hello,
Has any one idea how I can proceed to do the fatigue test of leaf spring in order to obtain the S-N curves?
Thanks

 

[rb1957]

build a leaf spring assembly,
decide a load to apply,
apply the load and release,
contiue until failure,
count the number of cycles.

if you're doing only one test, divide by 10 for safe life, if you're testing (say) 5 specimens, divide test life by 5.

altenatively, if you Really want an S/N curve ... test a gizzillion specimens (yes, that is the technical term) of different stress concentrations, cycle forms (min/max) of the leaf spring material.

 

[EngAddict]

Do you mean gazillion? There is nothhing technical about ficticious words.

But yes, the more simulations you run, the more accurate your results.

 

[rb1957]

sigh

 

[SAITAETGrad]

You do not need a material fatigue test (S-N curve development) in 2010 unless you have some new and/or exotic to work with. For most materials, the data is accessible (in the public domain or not) and was developed decades ago. Unless you work for a monolithic OEM and/or material manufacturer as a metallurgist, developing S-N curves is not for you. This is what RB was likely suggesting with the second half of his reply.

If you want to test your actual article, that's a different question as RB implied. I would suggest you find the fatigue life analytically rather than by test. But, if a test is required for QC or other reasons, RB's suggestion looks okay as a quick estimate. Examine the requirements for your actual program/industry.