Notched Fatigue Strength

Beta C Notched fatigue strength at high temperature... 

Room The notched fatigue strength at a ib s 3 de-Temperature creases as the strength level increases. (At aU... 

Corrosion fatigue refers to the reduction in ftitigue resistance of a metal due to the presence of a corrosive medium. Because of the protective oxide film of titanium, the smooth or notched fatigue strength of the more common titaniiun alloys and their weldments is not significantly affected by water, seawater, and many other aqueous chloride media. 

The recommended maximum design stress in tension is one-quarter the ultimate tensile strength (for cast irons a value up to 185 N/mm (12 tonf/ in. )). The fatigue strength is one-half the tensile strength. Notched... 

Fig. 8.75 Relation between (k — l)/n) and tj in 1% NaCl, where k is the ratio of fatigue strength in air to that in a corrosive environment, the notch sensitivity factor on fatigue strength, the corrosion current density at start of fatigue cycling, and jy the total life in...

Endo, K., Komai, K. and Nakamuro, N., Estimation of corrosion fatigue strength from corrosion resistance and notch sensitivity of the materials . Bull. Jap. Soc. Mech. Eng., 13, 837-46 (1970)... 

The fatigue strength of most TPs is about 20 to 30% of the ultimate tensile strength determined in the short-term test but higher for RPs. It decreases with increases in temperature and stress-cycle frequency and with the presence of stress concentration peaks, as in notched components. 

The forgings were evaluated by density, microstructure, surface finish, tensile strength, notched impact strength, ductility, and fatigue strength measurements... 

In spite of the importance that notches and stress concentrations can have in the design of structural parts, their influence on multiaxial fatigue strength has rarely been investigated [10,15,16,29,32,33]. It is difficult to draw general design indications from the few data available however, from at least one of the papers cited, some interesting conclusions can be obtained. 

The mechanical properties of aluminum-sprayed steel remain unimpaired other than a slight loss in fatigue strength owing to the notch effects caused by preliminary grit blasting. The fatigue... 

As with the work of Swain [7] and Subramanian [9], the S-N curve for the 8 series shows substantial differences between the performance of the A and O fiber sized composites. Reviewing the S-N curve for the 8 series compression-compression, R = 10 fatigue, a best fit line through each of the data sets assists in delineation of the difference in performance of the A and O interphases, as shown in Fig. 11.1. The apphed cyclic stress levels are presented as a percentage of their ultimate notched compression strength, as reported in Table 11.1. The 810-A composite exhibited a slightly lower rate of fife reduction with increasing load level. However, all lifetimes... 

Table lc.24 Influence of the notch factor on the fatigue strength of Ti6A14V... 

Notch Factor Stress Ratio R Fatigue Strength (MPa)... 

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