Evolution of Mechanical Properties of an AA 6061 T6 Aluminum alloy Processed by Cold Working (CW)
Öz
Nano scale grain size reduction (UFG) is one of three suitable methods for improving the mechanical properties of 6000 series aluminum alloys, by structural precipitation, strain hardening or by cold work hardening. For the cold working, several techniques are now available such as (ECAP - PC), (CEEA), (THP), (MM), (ARB), (CW). Cold work by compression high pressing (CW-CHP) can be applied in several cycles depending on the hardening behavior of the material. The influence of the nonmetric size of the grains produced by the (CW-CHP) of a cylindrical rolling machine with four passes of Sever plastic deformation with reduction ratios of (3.5, 10,18.8 and 28%), on the mechanical behavior of the alloy 6061 T6, was analyzed by determining the ultimate tensile strength (Rm), yield strength (Rp0.2, the strain hardening capacity SHC (Rm-Rp0.2), the work hardening coefficient n', the modulus of 'work hardening K' . The increase in the rate of work hardening by the reduction of the sample sections and consequently the reduction of the grain size at the first and the second pass, improves the mechanical properties of the alloy to the maximum values, and then the presence of crack initiation participates to the moderate decrease of the mechanical properties.
Anahtar Kelimeler
AA 6061T6, Cold working, Ultrafine grain, Mechanical properties, Sever plastic deformations
Kaynakça
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