The Role of Microstructural Processes in the Application of the Incremental Step Test to Determine the Cyclic Stress-Strain Curve of an Aluminium Alloy

Cyclic plasticity and fatigue of metals

“…A particularly noteworthy eature is the directional y' coarsening which was found to be most pronounced in out-of-phase tests and which occurred in such a manner that soft y-channels formed, inclined under an angle to the stress axis, thus promoting cyclic shear localization. tation-free, solid-solution hardened, and in the peak-aged states [1,3]. Acp1/2: plastic strain amplitude, stress amplitude.…”

“…This work addresses low-and high-temperature push-pull fatigue including thermomechanica 1 fatigue. Among the materials investigated are the age-hardenable aluminium alloy AlZnMgCu 0.5 which is similar to the alloy 7022 [1,3], martensitic and bainitic variants of the roller bearing steel SAE 52100, German designation 100Cr6 1 4 5 , the metastable austenitic steels of the AISI 304 L-series, German designations X 3 Cr k-d i 18 [1,2,6,7,8] and X 2 CrNi 19 11 [9,10,11], the normalized plain carbon steel SAE 1045, German desi nat~on Ck 45 [2,12], and the monocrystalline -(-hardened nickel-bare superalloy CMSX-6 RI~].…”

“…Transmission electron microscopy (TEM) observations on the aluminium alloy AlZnMgCu 0.5[1,3]. a) Solid-solution hardened state.…”

On the low-cycle fatigue behavior of thermo-mechanically processed high-strength aluminum alloys

“…However, strain localization induced by cutting of precipitates being to small needs to be avoided [50][51][52]. Coarse precipitates present in the specimen formed in the tool with a temperature of 350 °C result in a large interparticle spacing facilitating dislocation slip and formation of dislocation cell walls and substructures [53][54]. However, fine and disperse precipitates in the parts formed in the tools with temperatures of 24 °C and 350 °C cause a low interparticle spacing signifying dislocation-precipitate interactions.…”

Dynamic strain ageing and dynamic precipitation in AA7030 during cyclic deformation

“…The occurrence of DP during cyclic plastic deformation of aluminium alloys is so far largely unexplored. Christ et al [16] showed that a solution treated Al-Zn-Mg-Cu alloy, corresponding to AA7022, showed extensive cyclic hardening and drastically reduced fatigue life under low-cycle fatigue conditions, and this was shown to be a result of dynamic precipitation during cycling. Cyclically deformed Al-Ag alloys, heat treated to contain Guinier-Preston (GP) zones and shearable ' precipitates, showed evidence of deformation induced precipitation of stable phases, and even over-ageing [17,18].…”