The recycled copper alloy powders prepared by physical method were further alloyed, and therefore four medium entropy alloys (MEAs), (Fe40Ni40Mn20)50Cu50, (Fe38Ni38Mn19Al5)50Cu50, (Fe36Ni36Mn18Al10)50Cu50 and (Fe32Ni32Mn16Al20)50Cu50were successfully prepared via mechanical alloying (MA) and spark plasma sintering (SPS). The influence of Al content on the microstructure and mechanical properties of the MEAs were systematically studied. Following 60 h of MA, the mechanical alloyed powders of the four MEAs consist of a primary supersaturated FCC solid solution along with a trace amount of WC contaminants. Following SPS, the (Fe40Ni40Mn20)50Cu50, (Fe38Ni38Mn19Al5)50Cu50 and (Fe36Ni36Mn18Al10)50Cu50 show a dual-phase structure consisting of a Cu-rich phase (FCC1) and a Fe-Ni-rich phase (FCC2), displaying a multiscale grain structure of ultrafine grains and micron grains. However, the (Fe32Ni32Mn16Al20)50Cu50 alloy shows a primary Cu-rich phase (FCC1) with a small amount of Fe-Mn rich phase (FCC2) and Ni-Al rich B2 phase. The plasticity of the four MEAs is gradually decreased, while the strength and hardness are gradually increased with the increase of Al content. The compressive yield strength, compressive strength and Vickers hardness of (Fe40Ni40Mn20)50Cu50 MEAs are 878 MPa, 1257 MPa and 248.5HV, respectively. Compared with (Fe40Ni40Mn20)50Cu50, the compressive yield strength and hardness of (Fe32Ni32Mn16Al20)50Cu50 are increased by 50.1% and 50.4%, respectively, whereas the fracture strain is decreased from 19.55% to 8.31%.
CHENG P, YANG X D, YU T B. Study on the impact of mineral resources exploitation around cities on resident movement and health monitoring system[C]//4th International Symposium on Resource Exploration and Environmental Science. Ordos: IOP Conference Series: Earth and Environmental Science, 2020: 32005.
SVERDRUP H U , RAGNARSDOTTIR K V , KOCA D . An assessment of metal supply sustainability as an input to policy: security of supply extraction rates, stocks-in-use, recycling, and risk of scarcity[J]. Journal of Cleaner Production, 2017, 140, 359- 372.
SCHAFER P , SCHMIDT M . Discrete-point analysis of the energy demand of primary versus secondary metal production[J]. Environmental Science & Technology, 2020, 54 (1): 507- 516.
LIU F F , CHEN W P , WAN B B , et al. Recovery of high-grade copper from metal-rich particles of waste printed circuit boards by ball milling and sieving[J]. Environmental Technology, 2020, 43 (4): 514- 523.
YEH J W , CHEN S K , LIN S J , et al. Nanostructured high-entropy alloys with multiple principal elements: novel alloy design concepts and outcomes[J]. Advanced Engineering Materials, 2004, 6 (5): 299- 303.
MIRACLE D B , SENKOV O N . A critical review of high entropy alloys and related concepts[J]. Acta Materialia, 2017, 122, 448- 511.
FU Z Q , JIANG L , WARDINI J L , et al. A high-entropy alloy with hierarchical nanoprecipitates and ultrahigh strength[J]. Science Advances, 2018, 4 (10): 1- 8.
POLETTI M G , FIORE G , GILI F , et al. Development of a new high entropy alloy for wear resistance: FeCoCrNiW0.3 and FeCoCrNiW0.3+5 at.% of C[J]. Materials & Design, 2017, 115, 247- 254.
CHEN C , ZHANG H , FAN Y Z , et al. Improvement of corrosion resistance and magnetic properties of FeCoNiAl0.2Si0.2 high entropy alloy via rapid-solidification[J]. Intermetallics, 2020, 122, 106778.
ZHAO S J . Defect properties in a VTaCrW equiatomic high entropy alloy (HEA) with the body centered cubic (bcc) structure[J]. Journal of Materials Science & Technology, 2020, 44, 133- 139.
GU Z , XI S Q , SUN C F . Microstructure and properties of laser cladding and CoCr2.5FeNi2Tix high-entropy alloy composite coatings[J]. Journal of Alloys and Compounds, 2020, 819, 152986.
NAGASE T , SHIBATA A , MATSUMURO M , et al. Alloy design and fabrication of ingots in Cu-Zn-Mn-Ni-Sn high-entropy and Cu-Zn-Mn-Ni medium-entropy brasses[J]. Materials & Design, 2019, 181, 107900.
XU Z J , LI Z T , TONG Y , et al. Microstructural and mechanical behavior of a CoCrFeNiCu4 non-equiatomic high entropy alloy[J]. Journal of Materials Science & Technology, 2021, 60, 35- 43.
QIN G , CHEN R R , LIAW P K , et al. A novel face-centered-cubic high-entropy alloy strengthened by nanoscale precipitates[J]. Scripta Materialia, 2019, 172, 51- 55.
WU B , XIE Z Y , HUANG J C , et al. Microstructures and thermodynamic properties of high-entropy alloys CoCrCuFeNi[J]. Intermetallics, 2018, 93, 40- 46.
FU Z Q , MACDONALD B E , DUPUY A D , et al. Exceptional combination of soft magnetic and mechanical properties in a heterostructured high-entropy composite[J]. Applied Materials Today, 2019, 15, 590- 598.