Severe plastic deformation of 6061 aluminum alloy tube with pre and post heat treatments

Microstructure and mechanical properties of an Al–Mg–Si tube processed by severe plastic deformation and subsequent annealing

“…of annealing in similar temperature [21]. This has been explained by decrease of dislocation density besides arise of pre-ȕƍƍ precipitations which results in a balance between strengthening effect of precipitations and softening effect of restoration [21]. Collating with those results, the moderate strength increase of TCPed specimens after 2h of annealing is related to incidence of semi-coherent ȕƍƍ precipitations which causes more strengthening effect in comparison of coherent pre-ȕƍƍ precipitations [19,26].…”

“…However, little changes have been previously obtained for strength of TCPed specimens after 20 min. of annealing in similar temperature [21]. This has been explained by decrease of dislocation density besides arise of pre-ȕƍƍ precipitations which results in a balance between strengthening effect of precipitations and softening effect of restoration [21].…”

“…75 mm long specimens were cut from as received tube and subjected to solution treatment at 803° K for 1h. This solution treatment causes dissolution of almost all precipitations since after this treatment, no evidence of any precipitation was detected by X-Ray diffraction [7,[21][22].…”

“…Tension samples were machined parallel to longitudinal direction of specimen as illustrated previously [21,23]. The strength of specimens was obtained by tension tests at the room temperature using the strain rate of 5×10 -4 s -1 .…”

Microstructure evolutions and mechanical properties of tubular aluminum produced by friction stir back extrusion

“…Several SPD methods have been introduced including equal channel angular pressing (ECAP) [3], accumulative roll bonding (ARB) [4], high pressure torsion (HPT) [5], cyclic extrusion compression (CEC) [6], and continuous repetitive corrugation and straightening (CRCS) [7]. However, studies on SPD of tubular-form metals are confined to processes of tube channel pressing (TCP) [8,9], accumulative spin-bonding (ASB) [10], high pressure tube twisting (HPTT) [11], and tubular channel angular pressing (TCAP) [12,13].…”