| Abstract: | | 1. |
The characteristics of strength ( u, o  2), plasticity ( ,  ) in the longitudinal and transverse directions, impact toughness in the transverse direction, and also the nominal stress intensity factor K
c
*
are practically independent of the grain size of the alloy AMg6.
| | 2. |
The ultrafine-grained structure somewhat reduces the endurance of the alloy AMg6 in the region of low cycle fatigue and increases endurance and fatigue limit in the region of multicycle fatigue.
| | 3. |
Reduced grain size is accompanied by increased resistance to fatigue crack nucleation in alloy AMg6.
| | 4. |
Alloy AMg6 with ultrafine-grained structure is isotropic in crack resistance, and with coarse-grained structure it is anisotropic. The highest fatigue crack growth rate is found in transverse speciment of coarse-grained material.
| | 5. |
The effect of the grain size on crack resistance depends on the change of the ratio of resistance to crack nucleation and growth at high and low stress levels under conditions of variable loading.
|
Ufa Aviation Institute. All-Union Institute of Nonferrous Alloys (VILS). Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 8, pp. 42–44, August, 1988. |
