Issue 14

B. L 18 exp cyc Som cha min of An by Th the exp Me Ini com pro Go fati pro the In hig end sim dat wid mo stre S y . Ex obato da Silva erimental da les. This rela a A S   e practical a racterize the imum value the range stre m S S   m S S m  m S S a  d to describe Eq. 5. The re ma m S S R  1 1 a S    e standard co Eq. 1 can be erimental res ar S   an stress effect tially, empiri pensate the posed a par odman intro gue data in posed as imp fatigue stren order to ove h mean stre urance limit ilar to SWT, a, Eq. 14. A espread mat del consists i ss, S m , on th According to a S   pressed in fo a S   et alii, Frattura ta in the sen tion can be e b N pplications a constant am , Eq. 2. The ss is called am ax min S  2 min ax S  2 min ax S  the mean str lation betwe x in . m R S R ndition to de express in t ults. ' b f N  predition Mo c models w effect of m abolic repres duced a theo the graphic rovement of gth coefficie rcome the fa sses, Smith, for the load however usi ccording to hematical rel n the substit e limit of fati this model, m rt S ar e           rm of power m rt S ar e             ed Integrità Stru se to correla xpressed as i n nd also fatig plitude load mean stress, plitude stre ess, a factor en S a , S m e R termine the he form o f E dels ere proposed ean stress in entation of retical line t S a versus S m . the previou nt and that th ilure predicti Watson and ratio, R = -1 ng a factor  empiric con ations to des ution of the B gue strength the stress-life series, th e E 0 1 ! N i i S          tturale, 14 (201 te the alterna Eq. 1, wher ue tests in m s. The stres S m , is the ave ss, S a , Eq. 4. used to char is expressed parameters o q. 7. It is call by Gerber the high cyc the Wöhler’s o represent Since 1960, s models. Fat e compressio on’s problem Topper - S , S ar , is expre that makes siderations, cribe the effe asquin’s equ for the rever relation can q. 8 can be e i m rt    0) 17-26; DOI: te stress and e A and b ar aterials invol s range, S  rage between These are ba acterize the d in the Eq. 6. f Wöhler cur ed Basquin’s (1874), Go le fatigue st limit fatigu the evaluated some mode igue tests ind n normal m under load WT [3] prop ssed in the E possible an a Berkovits an ct of mean s ation’s const se load condi be presented xpressed by E 10.3221/IGF-ESI the numbe e the constan ve maximum , is the diff maximum v sic relations t egree of sym ve is to assum equation. W odman (189 rength, accor e data on th fatigue data ls to determ icate that the ean stress sho conditions w osed a mod q. 13. On th djustment o d Fang [5] tress on the ant, Eq. 7, fo tion, S rt , and by Eq. 8. q. 9: S.14.02 r of cycles to t and the cur and minimu erence betwe alue and mi hat character metry of the e alternating here  ’ f e b a 9), Haigh (1 ding to Lee e graphic S m , Eq. 11 . Ha ine the effec tensile norm uld increase ith relatively el in which is same year f the curve in and more r fatigue beha r a function on the ultim failure betw ve exponent, m constant l en the maxi nimum value ize one load load, load ra load, null m re material co 917) e Sode [1] and Dow ax /S u versus S igh was the t of mean s al mean stre i t [1]. low amplitu the equivale , Walker [4] p relation to ecently Kwo vior of endu that will dep ate strength, een 10 3 and respectively. (1) evel stresses mum value , Eq. 3. The cycle. (2) (3) (4) tio, R , is defi (5) (6) ean stress. T nstants base (7) rberg (1930) ling [2] . Ge min /S u , Eq. first to plot tress have b ss should red de and relati nt stress to resented crit the experime fie [6] propo rance limit. S end on the m or yield stren (8) (9) 10 6 that and half ned hus, d in to rber 12. the een uce vely the eria ntal sed uch ean gth,