Comparison of creep behavior for lead free solders Sn-3.5Ag, SAC305 and SAC387


  • Ramiro Vargas Obuda University
  • Viktor Gonda Obuda University


Lead-free solder, Creep, finite element analysis


Numerous lead-free solder compositions were developed recently to substitute the conventional lead-tin solder due to its environmental hazards. As an example, lead-free solders with tin-silver-copper (SAC) compositions are frequently used with various weigh percentage of the alloying elements. Beside the electronic properties of these solders, the mechanical behavior is of great interest, due to the time dependent nature arising from these low melting point materials operating at thermal-mechanical loads. In this paper, the thermal-mechanical creep behavior is analyzed for three lead-free solders of Sn-3.5Ag; SAC305 and SAC387. A simple structural configuration of an electronic package containing a solder joint is modeled in finite elements, where the applied load was thermal cycling. The Anand material model was employed for the creep behavior of the solder. Stress and strain analyses of the structural behavior was performed and compared for the tree different lead-free solders. Results are presented for the mechanical response of the different compositions.


[1] D. Charles, “Electrical apparatus and method of manufacturing the same,” 01-Dec-1925.
[2] G. O’Malley, J. Giesler, and S. Machuga, “The importance of material selection for flip chip on board assemblies,” IEEE Trans. Components, Packag. Manuf. Technol. Part B, vol. 17, no. 3, pp. 248–255, 1994.
[3] D. R. Frear, S. N. Burchett, H. S. Morgan, and J. H. Lau, Mechanics of solder alloy interconnects. Springer Science & Business Media, 1994.
[4] Y. Tsukada, H. Nishimura, M. Sakane, and M. Ohnami, “Fatigue Life Analysis of Solder Joints in Flip Chip Bonding,” J. Electron. Packag., vol. 122, no. 3, p. 207, 2000.
[5] D. S. Herman, M. Geraldine, C. C. Scott, and T. Venkatesh, “Health hazards by lead exposure: evaluation using ASV and XRF,” Toxicol. Ind. Health, vol. 22, no. 6, pp. 249–254, Jul. 2006.
[6] EUROPEAN PARLIAMENT; THE COUNCIL OF THE EUROPEAN UNION, “Directive 2002/95/EC of the European Parliament and of the Council of 27 January 2003 on the restriction of the use of certain hazardous substances in electrical and electronic equipment.,” Official Journal of the European Union, 2003. .
[7] EUROPEAN PARLIAMENT; THE COUNCIL OF THE EUROPEAN UNION, “DIRECTIVE 2011/65/EU OF THE EUROPEAN PARLIAMENT AND OF THE COUNCIL of 8 June 2011 on the restriction of the use of certain hazardous substances in electrical and electronic equipment (recast),” Official Journal of the European Union, 2011. .
[8] S. Cheng, C. M. Huang, and M. Pecht, “A review of lead-free solders for electronics applications,” Microelectron. Reliab., vol. 75, pp. 77–95, 2017.
[9] S. Yue, “Philips our experience in the introduction of leadfree soldering,” in 2004 International IEEE Conference on the Asian Green Electronics (AGEC). Proceedings of, pp. 18–25.
[10] M. E. Kassner, Fundamentals of Creep in Metals and Alloys. Elsevier, 2015.
[11] G. Dieter, “Mechanical Metallurgy.” p. 615, 1961.
[12] M. I. M. Ahmad, J. L. Curiel Sosa, and J. A. Rongong, “Characterisation of creep behaviour using the power law model in copper alloy,” J. Mech. Eng. Sci., vol. 11, no. 1, pp. 2503–2510, Mar. 2017.
[13] A. M. Brown and M. F. Ashby, “On the power-law creep equation,” Scr. Metall., vol. 14, no. 12, pp. 1297–1302, Dec. 1980.
[14] S. Spigarelli, “Creep of Aluminium and Aluminium Alloys,” Talat, p. 26, 1999.
[15] C. Kittel, Introduction to solid state physics, vol. 8. Wiley New York, 1976.
[16] S. D. Mesarovic, “Lattice continuum and diffusional creep,” Proc. R. Soc. A Math. Phys. Eng. Sci., vol. 472, no. 2188, 2016.
[17] F. R. N. Nabarro, “Report of a Conference on the Strength of Solids,” Phys. Soc. London, vol. 75, 1948.
[18] C. Herring, “Diffusional viscosity of a polycrystalline solid,” J. Appl. Phys., vol. 21, no. 5, pp. 437–445, 1950.
[19] G. FANTOZZI, J. CHEVALIER, C. OLAGNON, and J. L. CHERMANT, “Creep of Ceramic Matrix Composites,” in Comprehensive Composite Materials, Elsevier, 2000, pp. 115–162.
[20] R. L. Coble, “A model for boundary diffusion controlled creep in polycrystalline materials,” J. Appl. Phys., vol. 34, no. 6, pp. 1679–1682, 1963.
[21] J. Harper and J. E. Dorn, “Viscous creep of aluminum near its melting temperature,” Acta Metall., vol. 5, no. 11, pp. 654–665, 1957.
[22] P. Yavari, D. A. Miller, and T. G. Langdon, “An investigation of harper-dorn creep—I. Mechanical and microstructural characteristics,” Acta Metall., vol. 30, no. 4, pp. 871–879, Apr. 1982.
[23] C. R. Barrett, E. C. Muehleisen, and W. D. Nix, “High temperature-low stress creep of Al and Al+ 0.5% Fe,” Mater. Sci. Eng., vol. 10, pp. 33–42, 1972.
[24] F. A. Mohamed, K. L. Murty, and J. W. Morris, “Harper-dorn creep in al, pb, and sn,” Metall. Trans., vol. 4, no. 4, pp. 935–940, 1973.
[25] MSC Software Corporation, Theory and User Information. 2018.
[26] L. Anand, “Constitutive Equations for the Rate-Dependent Deformation of Metals at Elevated Temperatures,” J. Eng. Mater. Technol., vol. 104, no. 1, p. 12, 1982.
[27] D. Lee and F. Zaverl Jr, “A generalized strain rate dependent constitutive equation for anisotropic metals,” Acta Metall., vol. 26, no. 11, pp. 1771–1780, 1978.
[28] L. Anand, “Constitutive equations for hot-working of metals,” Int. J. Plast., vol. 1, no. 3, pp. 213–231, 1985.
[29] S. B. Brown, “An Internal Variable Constitutive Model for the Thixotropic Behavior of Metal Semi-Solid Slurries,” Materials Science Seminar on Intelligent Processing of Materials, vol. 5. pp. 95–130, 1989.
[30] N. Bai, X. Chen, and H. Gao, “Simulation of uniaxial tensile properties for lead-free solders with modified Anand model,” Mater. Des., vol. 30, no. 1, pp. 122–128, 2009.
[31] M. Basit, M. Motalab, J. C. Suhling, and P. Lall, “Viscoplastic Constitutive Model for Lead-Free Solder Including Effects of Silver Content, Solidification Profile, and Severe Aging,” in Volume 2: Advanced Electronics and Photonics, Packaging Materials and Processing; Advanced Electronics and Photonics: Packaging, Interconnect and Reliability; Fundamentals of Thermal and Fluid Transport in Nano, Micro, and Mini Scales, 2015, p. V002T01A002.
[32] J. H. L. Pang, Lead Free Solder, vol. 9781461404. New York, NY: Springer New York, 2012.
[33] National Institute of Standards and Technology (NIST), “Sn-Ag Properties and Creep Data.” [Online]. Available:
[34] T. T. Nguyen, D. Yu, and S. B. Park, “Characterizing the mechanical properties of actual SAC105, SAC305, and SAC405 solder joints by digital image correlation,” J. Electron. Mater., vol. 40, no. 6, pp. 1409–1415, 2011.
[35] National Institute of Standards and Technology (NIST), “Sn-Ag-Cu Properties and Creep Data.” [Online]. Available:
[36] Q. J. Yang, X. Q. Shi, Z. P. Wang, and Z. F. Shi, “Finite-element analysis of a PBGA assembly under isothermal/mechanical twisting loading,” Finite Elem. Anal. Des., vol. 39, no. 9, pp. 819–833, 2003.
[37] J. R. Davis, “ASM specialty handbook,” Stainl. Steel, vol. 10, 1994.




Folyóirat szám


Materials Science and Technology (Anyagtudomány és Technológia)