A free-cutting and ductile CuAlMnZnTiB shape memory alloy

Abstract

The mechanical properties and cutting performance of the designed CuAlMnZnTiB shape memory alloy were studied by tensile test and microstructure observation. Using X-ray diffractometry, differential scanning calorimetry (DSC) and semi-quantitative shape memory effect test, the microstructure and shape memory effect were analyzed. It is found that lots of β phase and few α phase are formed in the quenching of Cu-7.5Al-9.7Mn-3.4Zn-0.3Ti-0.14B (mass fraction, %) alloy, a great deal of martensite and few α phase are formed in the aging alloy, while the annealing alloy is composed of a great deal of α phase and few β phase. The tensile strength and elongation of the annealed alloy are 649 MPa and 17.1%, respectively. Some tiny and dispersion distributed second phase particles are generated in Ti and B precipitates, greatly improving the alloy machinability.

Keywords

CuAlMnZnTiB shape memory alloy / mechanical properties / free-cutting

References

[1] LiuH-x, SiN-c, XuG-fang. Influence of process factors on shape memory effect of CuZnAl alloys [J]. Transactions of Nonferrous Metals Society of China, 2006, 16: 1402-1409

[2] GongS, LiZ, XuG Y, LiuN, ZhaoY Y, LiangS Q. Fabrication, microstructure and property of cellular CuAlMn shape memory alloys produced by sintering-evaporation process [J]. Journal of Alloys and Compounds, 2011, 509(6): 2924-2928

[3] JiaoY-q, WenY-h, LiN, HeJ-q, TengJin. Effect of environmental temperature on damping capacity of Cu-Al-Mn alloy [J]. Transactions of Nonferrous Metals Society of China, 2009, 19: 616-619

[4] CingolaniE, van HumbeeckJ, AhlersM. Stabilization and two-way shape memory effect in Cu-Al-Ni single crystals [J]. Metallurgical and Materials Transactions A, 1999, 30: 493-499

[5] ChungC Y, LanC W H. Cu-based shape memory alloys with enhanced thermal stability and mechanical properties [J]. Materials Science and Engineering A, 1999, 273–275: 622-624

[6] JiangS-y, ZhangY-q, ZhaoY-n, TangM, YiW-lin. Constitutive behavior of Ni-Ti shape memory alloy under hot compression [J]. Journal of Central South University, 2013, 20(1): 24-29

[7] ZhangP, MaA-b, JiangJ-h, LuS, LinP-h, YangD-h, LiuG-guo. Microstructural evolution and mechanical response of Cu-Al-Be-B shape memory alloy processed by repetitive equal channel angular pressing [J]. Journal of Alloys and Compounds, 2010, 497(1/2): 210-214

[8] KainumaR, TakahashiS, IshidaK. Thermoelastic martensite and shape memory effect in ductile Cu-Al-Mn alloys [J]. Metallurgical and Materials Transactions A, 1996, 27: 2187-2195

[9] JiaG-b, YangB, LiuD-chun. Deeply removing lead from Pb-Sn alloy with vacuum distillation [J]. Transactions of Nonferrous Metals Society of China, 2013, 23: 1822-1831

[10] El-SherifR M, IsmailK M, BadawyW A. Effect of Zn and Pb as alloying elements on the electrochemical behavior of brass in NaCl solutions [J]. Electrochimica Acta, 2004, 49: 5139-5150

[11] SilbergeldE K, WaalkesM, RiceJ M. Lead as a carcinogen: Experimental evidence and mechanisms of action [J]. American Journal of Industrial Medicine, 2000, 38: 316-323

[12] Loghman-AdhamM. Renal effects of environmental and occupational lead exposure [J]. Environmental Health Perspectives, 1997, 105(9): 928-938

[13] CanfieldR L, HendersonC R, Cory-SlechtaD A, CoxC, JuskoT A, LanphearB P. Intellectual impairment in children with blood lead concentrations below 10 μg per deciliter [J]. The New England Journal of Medicine, 2003, 348(16): 1517-1526

[14] ParkinsonD K, HodgsonM J, BrometE J, DewM A, ConnellM M. Occupational lead exposure and blood pressure [J]. British Journal of Industrial Medicine, 1987, 44: 744-748

[15] ZhongK-b, GuiM, ZhuL-y, LiW, GuanC-x, GuoF-qiu. Heavy metals accumulation effect in rabbit body fluids after smoking [J]. Journal of Central South University, 2011, 18(5): 1408-1412

[16] PuttlitzK J, GalyonG T. Impact of the ROHS directive on high-performance electronic systems. Part I: Need for lead utilization in exempt systems [J]. Journal of Materials Science: Materials in Electronics, 2007, 18: 331-346

[17] Öko-Tex Standard 100.Öko-Tex-Initiative [S], 2014

[18] LiS, KondohK, ImaiH, AtsumiH. Fabrication and properties of lead-free machinable brass with Ti additive by powder metallurgy [J]. Powder Technology, 2011, 205: 242-249

[19] AtsumiH, ImaiH, LiS, KondohK, KousakaY, KojimaA. High-strength, lead-free machinable α-β duplex phase brass Cu-40Zn-Cr-Fe-Sn-Bi alloys [J]. Materials Science and Engineering A, 2011, 529: 275-281

[20] ImaiH, KosakaY, KojimaA, LiS, KondohK, UmedaJ, AtsumiH. Characteristics and machinability of lead-free P/M Cu60-Zn40 brass alloys dispersed with graphite [J]. Powder Technology, 2010, 198: 417-421

[21] SueyoshiH, InoueK, YamanoY, MaedaY, YamadaK. Machinability of copper sulfide-dispersed lead-free bronze [J]. Materials Transactions, 2009, 50(4): 847-852

[22] ZedanY, AlkahtaniS. Influence of the microstructure on the machinability of heat-treated Al-10.8% Si cast alloys: Role of copper-rich intermetallics [J]. Journal of Materials Processing Technology, 2013, 213: 167-179

[23] ZhuQ-l, ZhangX-m, LuoL-s, LiW, ChenW-p, WangG-l, LiChen. Microstructure and properties of lead-free P-Ca brasses [J]. The Chinese Journal of Nonferrous Metals, 2012, 22(5): 1421-1429

[24] MurrayJ L. The Cu-Ti (copper-titanium) system [J]. Bulletin of Alloy Phase Diagrams, 1983, 4(1): 81-95

[25] ArroyaveR, EagarT W, KaufmanL. Thermodynamic assessment of the Cu-Ti-Zr system [J]. Journal of Alloys and Compounds, 2003, 351: 158-170

[26] YukinobuM, OgawaO, GotoS. Activities of boron in the binary Fe-B, Co-B, and Cu-B melts [J]. Metallurgical and Materials Transactions B, 1989, 20: 705-710

[27] ChenD, DongJ-f, MaG-zhi. Synthesis and compressive fracture behavior of a CuZr-based bulk amorphous alloy with Ti addition [J]. Journal of Central South University of Technology, 2013, 20: 1137-1141

[28] MurrayJ L, LiaoP K, SpearK E. The B-Ti (boron-titanium) system [J]. Bulletin of Alloy Phase Diagrams, 1986, 7(6): 550-555

[29] LeeJ S, WaymanC M. Grain refinement of a Cu-Al-Ni shape memory alloy by Ti and Zr additions [J]. Transactions of the Japan Institute of Metals, 1986, 27(8): 584-591

[30] ZhaoP, GladmanT. Grain refinement of HSLA steel by second phase particles [J]. Journal of University of Science and Technology Beijing, 1993, 15(5): 472-478

[31] TangS M, ChungC Y, LiuW G. Preparation of Cu-Al-Ni-based shape memory alloys by mechanical alloying and powder metallurgy method [J]. Journal of Materials Processing Technology, 1997, 63: 307-312

[32] HuangY-c, XiaoZ-b, LiuYu. Crystallography of Zr poisoning of Al-Ti-B grain refinement using edge-to-edge matching model [J]. Journal of Central South University, 2013, 20: 2635-2642

[33] ZhaoH-l, GuanR-g, LiM, YueJ-s, GaoYa. Microstructrue and phase forming process of Al-3Ti-0.2C-1RE grain refiner [J]. Journal of Central South, 2014, 21: 1-8

[34] NunesR, AdamsJ H, AmmonsM, AveryH SASM metals handbook, Volume 2: Properties and slection: Nonferrous alloys and special-purpose materials [M], 1923, Metals Park, OH, ASM International: 792-825

[35] VilarinhoC, DavimJ P, SoaresD, CastroF, BarbosaJ. Influence of the chemical composition on the machinability of brasses [J]. Journal of Materials Processing Technology, 2005, 170: 441-447

[36] SakaiK OLead-free free-cutting copper alloys: US 6413330 [P], 2002