Cyclic stress-strain response of polycrystalline copper in constant and variable amplitude fatigue

✍ Scribed by V.-T. Kuokkala; P. Kettunen

• Publisher: Elsevier Science
• Year: 1985
• Weight: 822 KB
• Volume: 33
• Category: Article
• ISSN: 0001-6160
• DOI: 10.1016/0001-6160(85)90127-0

✦ Synopsis

Cyclic stress-strain response of polycrystalline copper of two different grain sizes was studied in constant, incremental step and variable plastic strain amplitude fatigue tests. The multi-regime css curves of largcgraincd samples exhibited short but distinct plateaus both in constant and variable amplitude tests, but not in the incremental step tests. With small-grained samplea, the css curve of random amplitude tests did not show the plateau but only a region with a small positive slope. The ef&tivc amplitude of the random squan distributed loading block was estimated to be about 25% below the maximum amplitude of the block. R&amn&Nous avons &t&i& la r&onse ~nt~n~fo~tion cychquc de palycristaux de cuivre de dewi di&entcs gromeum de grains, Par des cm& de fatigue B amplitude de d&formation plastiquc consbutte, en &aPrs croimantcs, et B amplitude variable. Les courbcs CDC dcs 6chantiilons i gros grains ont fait voir de courts, mais disthtcts plateaux, aussi bicn dans ks es& H amplitude constame que dans caux i amplitude variable, mair pas dans les essais B &apes croissantca. Pour ks cC~tiU0~ i grains Anr, la courhe CDC des c&s i amplitudss prigs au has&, nous n'avons pas observ6 dc plateau, mais scukunent uric r&ion avcc une &g&e lnclinaison positive. L'amplitudc &ctivc de s+mcnt de @ r&pandu uniform&mcnt a c1c atim& ctm environ 25% au dcssous de l'amplitude maxim& du &merit.