Question

4 Three identical fatigue specimens (denoted A, B, and C) are fabricated from a nonferrous alloy. Each is subjected to one of the maximum-minimum stress cycles listed below; the frequency is the same for all three tests. Specimen Guat (MPa) +470 +390 +350 Ơmin (MPa) 380 -280 350 (a) Rank the fatigue lifetimes of these three specimens from the longest to the shortest. (b) Now justify this ranking using a schematic S-N plot.

Answer 1

eメー Giventhot Prom a ron Perrous ola mle) 55ma

Lag to dta orgeot to shoutot lile ture as

390 250