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The hot deformation behaviors of single- and two-phase CuAlMn shape memory alloy were studied. Isothermal compression tests were conducted at different temperatures from 400 degrees C to 800 degrees C and various strain rates from 0.001/S to 1/S. At the temperature below 500 degrees C, CuAlMn alloy had a two-phase microstructure (FCC alpha phase + L2(1) beta phase); while at the temperature higher than 550 degrees C, the alloy had a single beta phase structure. The flow stress curves showed the stress drop for all samples, indicating a dynamic recrystallization (DRX) feature of the alloy. The local minimum value of stress drop appeared at 500 degrees C. The thermal active energy (Q) were calculated to be 418.7 kJ mol(-1) for alpha + beta alloy at 400-500 degrees C and 219.7 kJ mol(-1) for beta alloy at 550-800 degrees C, respectively. The artificial neural network (ANN) model showed a high precision to predict the flow stress of the studied alloy at a wide range of temperature. Based on the dynamic material model (DMM) theory, the processing map of the alloy that consists of the contour lines of the power dissipation factor, it, and the instability criteria was established. The grains were refined to a micron level and DRX of alpha phase occurred during the deformation between 400 - 500 degrees C at the low strain rate. The hot deformation behaviors of the alloy at the low temperature (400 - 450 degrees C) mainly depended on the deformation of alpha phase. The optimum deformation parameters for the single-phase CuAlMn alloys were 750-800 degrees C/0.1-1 s(-1) . (C) 2020 Elsevier B.V. All rights reserved.
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