Microstructural insights into the mechanical and electrical behavior of CuCrZr alloy subjected to sequential cryogenic deformation and aging treatments

Abstract

The effect of cryo-rolling-aging treatments with different sequences on the mechanical properties and electrical conductivity of a highly alloyed Cu-1Cr-0.15Zr alloy for use in metallic molds is investigated. In this regard, X-ray diffraction and transmission electron microscopy are used to characterize the prepared samples under various cryo-rolled and aged conditions. According to the results of the differential scanning calorimetry analysis and hardness measurement, the optimal aging treatment condition is 120 min at 460 °C. It is found that among different sequential cryogenic deformation and heat treatments, aging at 460 °C and then 90% cryo-rolling lead to the highest ultimate tensile strength (680 MPa), while the 90% cryo-rolling and then ageing at 460 °C result in the highest yield strength (540 MPa) associated with low work hardening capability in CuCrZr alloy. Moreover, the two-stage treatment has the most deformation energy along with appropriate electrical conductivity. According to TEM images and XRD results, depending on the sequences of heat treatment and deformation, the microstructure characteristics vary, i. e., precipitates size and dislocation density varying from 3 to 18 nm and 2×10¹³ to 12×10¹³ m⁻², respectively. It is shown that these microstructural features affect the product’s mechanical behavior and electrical conductivity.

Keywords

CuCrZr alloy / cryogenic deformation / heat treatment / mechanical properties / electrical conductivity

References

[1] Nasution F P, Sævik S, Gjøsteen J KØ. Fatigue analysis of copper conductor for offshore wind turbines by experimental and FE method [J]. Energy Procedia, 2012, 24: 271-280

[2] Brewitt N, Andrew S, Ian C, et al.. Failure of copper wires in a railway motor operation contact [J]. Engineering Failure Analysis, 2020, 108: 104214

[3] Niu Z Y, Cai Z, Zhu M. Heat transfer behaviour of funnel mould copper plates during thin slab continuous casting and channel structure optimization [J]. Ironmaking & Steelmaking, 2020, 47(10): 1135-1147

[4] Kelly A L, Mulvaney-Johnson L, Beechey R, et al.. The effect of copper alloy mold tooling on the performance of the injection molding process [J]. Polymer Engineering & Science, 2011, 51(9): 1837-1847

[5] Kulczyk M, Pachla W, Godek J, et al.. Improved compromise between the electrical conductivity and hardness of the thermo-mechanically treated CuCrZr alloy [J]. Materials Science and Engineering A, 2018, 724: 45-52

[6] Chen X, Jiang F, Jiang J, et al.. Precipitation, recrystallization, and evolution of annealing twins in a Cu-Cr-Zr alloy [J]. Metals, 2018, 8(4): 227

[7] Wang Y D, Liu F C, Xue P, et al.. Thermal stability behaviors of ultrafine-grained Cu-Cr-Zr alloy processed by friction stir processing and rolling methods [J]. Journal of Alloys and Compounds, 2023, 950: 169957

[8] Sun L X, Tao N R, Lu K. A high strength and high electrical conductivity bulk CuCrZr alloy with nanotwins [J]. Scripta Materialia, 2015, 99: 73-76

[9] Zhang S, Li R, Kang H, et al.. A high strength and high electrical conductivity Cu-Cr-Zr alloy fabricated by cryorolling and intermediate aging treatment [J]. Materials Science and Engineering A, 2017, 680: 108-114

[10] Lai Z, Peng K, Gao B, et al.. Achieving high strength and high electrical conductivity in Cu-Cr-Zr alloy by modifying shear banding during rolling [J]. Journal of Alloys and Compounds, 2023, 958: 170402

[11] Miao Y, Gan C, Jin W, et al.. Effect of aging temperature on microstructure and softening property of the Cu-Cr-Zr-Nb alloy [J]. Journal of Alloys and Compounds, 2024, 983: 173818

[12] Zhang K, Yang J, Li J, et al.. Effect of deformation and aging treatment on the microstructure and properties of Cu-0.45Cr-0.14Ti (wt.%) alloy [J]. Journal of Alloys and Compounds, 2021, 851: 156776

[13] Liang Y, Wang X, Qiu Y, et al.. Optimizing mechanical and electrical properties of Cu-3Zr alloy by thermomechanical processing [J]. Journal of Materials Research and Technology, 2024, 30: 603-612

[14] Liang N, Liu J, Lin S, et al.. A multiscale architectured CuCrZr alloy with high strength, electrical conductivity and thermal stability [J]. Journal of Alloys and Compounds, 2018, 735: 1389-1394

[15] Wu X, Zhang J, Zhao J, et al.. Enhancing the strength and conductivity of commercialized Cu-Cr-Zr plate through simple high strain cold rolling and aging [J]. Materials Characterization, 2023, 205: 113213

[16] Wei K, Wei W, Wang F, et al.. Microstructure, mechanical properties and electrical conductivity of industrial Cu-0.5%Cr alloy processed by severe plastic deformation [J]. Materials Science and Engineering A, 2011, 528(3): 1478-1484

[17] Sousa T G, de Brito Moura I A, da Costa Garcia Filho F, et al.. Combining severe plastic deformation and precipitation to enhance mechanical strength and electrical conductivity of Cu-0.65Cr-0.08Zr alloy [J]. Journal of Materials Research and Technology, 2020, 9(3): 5953-5961

[18] Li G Y, Li S Y, Li L, et al.. A high strength and high electrical conductivity CuCrZr alloy prepared by aging and subsequent cryorolling [J]. Vacuum, 2021, 190: 110315

[19] Shangina D V, Bochvar N R, Morozova A I, et al.. Effect of chromium and zirconium content on structure, strength and electrical conductivity of Cu-Cr-Zr alloys after high pressure torsion [J]. Materials Letters, 2017, 199: 46-49

[20] Zayed E M, Shazly M, El-Sabbagh A, et al.. Deformation behavior and properties of severe plastic deformation techniques for bulk materials: A review [J]. Heliyon, 2023, 9(6): e16700

[21] Meng A, Nie J, Wei K, et al.. Optimization of strength, ductility and electrical conductivity of a Cu-Cr-Zr alloy by cold rolling and aging treatment [J]. Vacuum, 2019, 167: 329-335

[22] Fu H, Xu S, Li W, et al.. Effect of rolling and aging processes on microstructure and properties of Cu-Cr-Zr alloy [J]. Materials Science and Engineering A, 2017, 700: 107-115

[23] Wang Y D, Wu L H, Xue P, et al.. Improved strength with good conductivity in Cu-Cr-Zr alloys: Determinant effect of under-aging treatment before rolling and aging [J]. Materials Science and Engineering A, 2022, 848: 143395

[24] Ma B, An B, Zhao X, et al.. Microstructure and properties of Cu-Cr-Zr alloy by doping Sc [J]. Materials Letters, 2023, 336: 133917

[25] Li Z, Zhou M, Jing K, et al.. Effects of different Cr contents on microstructure, mechanical and electrical properties of Cu-Zr-Cr alloy [J]. Materials Today Communications, 2024, 38: 108408

[26] Shen D P, Xu N, Gong M Y, et al.. Improved tensile strength and electrical conductivity in Cu-Cr-Zr alloys by controlling the precipitation behavior through severe warm rolling [J]. Journal of Materials Science, 2020, 55(26): 12499-12512

[27] KočiIško R, Kvačkaj T, KováčOvá A, et al.. The mechanical properties of OFHC copper and CuCrZr alloys after asymmetric rolling at ambient and cryogenic temperatures [J]. Open Engineering, 2018, 8(1): 426-431

[28] Li J, Ding H, Li B. Study on the variation of properties of Cu-Cr-Zr alloy by different rolling and aging sequence [J]. Materials Science and Engineering A, 2021, 802: 140413

[29] Yang H, Wang W, Wang C, et al.. Effects of aging process on properties and precipitation kinetics of Cu-Cr-Zr alloy strips [J]. Transactions of Nonferrous Metals Society of China, 2023, 33(8): 2439-2448

[30] Li J, Ding H, Li B, et al.. Microstructure evolution and properties of a Cu-Cr-Zr alloy with high strength and high conductivity [J]. Materials Science and Engineering A, 2021, 819: 141464

[31] Sun X, Jie J, Wang T, et al.. Effect of two-step cryorolling and aging on mechanical and electrical properties of a Cu-Cr-Ni-Si alloy for lead frames applications [J]. Materials Science and Engineering A, 2021, 809: 140521

[32] Kapoor K, Lahiri D, Batra I S, et al.. X-ray diffraction line profile analysis for defect study in Cu-1 wt.% Cr-0.1 wt.% Zr alloy [J]. Materials Characterization, 2005, 54(2): 131-140

[33] Devesa S, Rooney A P, GraçA M P, et al.. Williamson-hall analysis in estimation of crystallite size and lattice strain in Bi_1.34Fe_0.66Nb_1.34O_6.35 prepared by the sol-gel method [J]. Materials Science and Engineering B, 2021, 263: 114830

[34] Williamson G K, Smallman R E. III. Dislocation densities in some annealed and cold-worked metals from measurements on the X-ray Debye-scherrer spectrum [J]. Philosophical Magazine, 1956, 1(1): 34-46

[35] Wang W, Zhang Y, Yang H, et al.. Effects of Si addition on properties and microstructure of CuCrZr alloy [J]. Journal of Alloys and Compounds, 2022, 906: 164277

[36] Li R, Guo E, Chen Z, et al.. Optimization of the balance between high strength and high electrical conductivity in CuCrZr alloys through two-step cryorolling and aging [J]. Journal of Alloys and Compounds, 2019, 771: 1044-1051

[37] Li L, Kang H, Zhang S, et al.. Microstructure and properties of Cu-Cr-Zr(Mg) alloys subjected to cryorolling and aging treatment [J]. Journal of Alloys and Compounds, 2023, 938: 168656

[38] Wang W, Zhou S, Xiao Z, et al.. Effect of aging treatment and equal channel angular pressing on microstructure evolution and properties of a CuCrZrSc alloy [J]. Journal of Alloys and Compounds, 2022, 925: 166624

[39] Rezayat M. Deformation mechanism in particulate metal matrix composites [J]. Journal of Alloys and Compounds, 2022, 890: 161512

[40] Rezayat M, Parsa M H, Mirzadeh H, et al.. A dislocation assisted self-consistent constitutive model for the high-temperature deformation of particulate metal-matrix composite [J]. Philosophical Magazine, 2021, 101(3): 276-305

[41] Wang Z, Ning Y, Di P, et al.. Understanding the fracture mechanisms of Ni-Co-Cr-type superalloys: Role of precipitate evolution and strength degradation [J]. Materials Science and Engineering A, 2024, 902: 146623

[42] Zhang P, Jie J, Gao Y, et al.. Preparation and properties of TiB₂ particles reinforced Cu-Cr matrix composite [J]. Materials Science and Engineering A, 2015, 642: 398-405

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