Page 281 - Failure Analysis Case Studies II

266
--p
Comer
radius in I I f
,/ i' _.

.........
................
........... ...... ........... '\'\,\
.................
........ ..... ..... ...........................
........ ....... . . . .........................
.................
........................
.............
.............................
.............
----.-g-.-.- ......... ____-- _---
1
Fig. 10. Examples of relief grooves behind the shoulder to reduce the stress concentration at the radius, r. (Peterson's
Stress Concentration Factors, Walter D. Pilkey, e) 1997 . Reprinted by permission of John Wiley & Sons .)
radius, increasing the radius causes a decrease in both the elastic and fatigue stress concentrations.
Reducing the stress concentration decreases the effective stress at the shoulder, avoiding plastic
deformation and increasing the fatigue lifetime.

References

[l] Newby JR. ASM handbook, mechanical testing, Vol. 8, 1985. pp. 82.
[2] Callister WD. Materials science and engineering. New York: John Wiley & Sons, 1994. pp. 132.
[3] Peterson RE. Design factors for stress concentration. Machine Design 1951;5(23): 159-161.
[4] Shigley JE, Mischke CR. Mechanical engineering design. St. Louis: McGraw-Hill Inc., 1989.
[5] Lampman SR. ASM handbook, fatigue and fracture, Vol. 19, 1996. pp. 233, 969.
[6] Hertzberg RW. Deformation and fracture mechanics of engineering materials. New York: John Wiley & Sons, 1996.
pp. 530-32.
[7] Pilkey W. Peterson's stress concentration factors. New York: John Wiley and Sons, 1997. pp. 146-7.
[8] Peterson RE, Sines G. editors. Metal fatigue. New York: McGraw-Hill Book Company, Inc., 1959. pp. 296-7.