Effects of annealing at high pressure on structure and mechanical properties of Al87Ni7Gd6 metallic glass

Effects of Annealing and Pressure on Devitrification and Mechanical Properties of Amorphous Al87Ni7Gd6

“…The first and second peaks correspond to the formation of fcc aluminum nanocrystals, while the third peak corresponds to the formation of intermetallics. [3,4,6] The as-received ribbon, i.e., as-melt-spun specimen exhibited an onset temperature for the first peak of T x1 = 189°C. The DSC traces for the as-received and ribbons isothermally annealed for 30 minutes at atmospheric pressure are provided in Figure 3.…”

“…6-Particle size distribution for ribbon specimens isothermally annealed with and without 940 MPa pressure. [3,13,14] . …”

“…This may have importance in the processing of these materials as well as provide insight to the mechanisms of devitrification, because both acceleration [7][8][9] and deceleration [10][11][12] of kinetics have been reported in different systems. The present work was undertaken in order to extend our previous work [3,13,14] in these areas, while comparing results to other investigations. [2,[6][7][8][9][10][11][12] …”

“…[15] The ribbons had a thickness of approximately 25 and 33 lm, respectively. Ribbon materials were stored under refrigeration to minimize diffusion-related changes at room temperature, while characterization by X-ray diffraction (XRD), differential scanning calorimetry (DSC), and transmission electron microscopy (TEM) was performed, as described by Ko et al [3] Isothermal annealing treatments were conducted on 30-to 40-mm-long individual specimens for 30 minutes in silicone oil (GE, USEP SF 1147) maintained at 123°C, 145°C, 158°C, 173°C, 188°C, 191°C, 205°C, 232°C, and 262°C in an Innovare hydrostatic extrusion rig. [16] Additional isothermal annealing experiments were conducted at 123°C, 145°C, 158°C, 173°C, 188°C, 191°C, 205°C, and 232°C in oil, which was maintained at 940 MPa superimposed pressure in the Innovare hydrostatic extrusion rig.…”

“…Recent work has focused on the Al-Ni-Gd system and variants [3,4] to explore processing paths for the creation of useful materials with a balance of properties. In this regard, the effects of annealing conditions (i.e., temperature, pressure, and time) were explored to determine the range of properties possible with controlled treatments and to compare these to recent reviews of properties.…”