naa a22 4500 510803636 CHVBK 20180411083407.0 cr unu---uuuuu 180411e20130301xx s 000 0 eng 10.1007/s11664-012-2351-8 doi (NATIONALLICENCE)springer-10.1007/s11664-012-2351-8 Impact of Thermal Aging on the Microstructure Evolution and Mechanical Properties of Lanthanum-Doped Tin-Silver-Copper Lead-Free Solders [Elektronische Daten] [Muhammad Sadiq, Raphaël Pesci, Mohammed Cherkaoui] An extensive study is made to analyze the impact of pure lanthanum on the microstructure and mechanical properties of Sn-Ag-Cu (SAC) alloys at high temperatures. Different compositions are tested; the temperature applied for the isothermal aging is 150°C, and aging times of 10h, 25h, 50h, 100h, and 200h are studied. Optical microscopy with cross-polarized light is used to follow the grain size, which is refined from 8mm to 1mm for as-cast samples and is maintained during thermal aging. Intermetallic compounds (IMCs) present inside the bulk Sn matrix affect the mechanical properties of the SAC alloys. Due to high-temperature exposure, these IMCs grow and hence their impact on mechanical properties becomes more significant. This growth is followed by scanning electron microscopy, and energy-dispersive spectroscopy is used for elemental mapping of each phase. A significant refinement in the average size of IMCs of up to 40% is identified for the as-cast samples, and the coarsening rate of these IMCs is slowed by up to 70% with no change in the interparticle spacing. Yield stress and tensile strength are determined through tensile testing at 20°C for as-cast samples and after thermal aging at 150°C for 100h and 200h. Both yield stress and tensile strength are increased by up to 20% by minute lanthanum doping. TMS, 2013 Lanthanum nationallicence SAC alloys nationallicence intermetallic compounds nationallicence aging temperature nationallicence aging time nationallicence Sadiq Muhammad George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, 801 Ferst Drive NW, 30332, Atlanta, GA, USA aut Pesci Raphaël ENSAM-Arts et Métiers ParisTech, LEM3 UMR CNRS 7239, 4 rue Augustin Fresnel, 57078, Metz, France aut Cherkaoui Mohammed George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, 801 Ferst Drive NW, 30332, Atlanta, GA, USA aut Journal of Electronic Materials Springer US; http://www.springer-ny.com 42/3(2013-03-01), 492-501 0361-5235 42:3<492 2013 42 11664 https://doi.org/10.1007/s11664-012-2351-8 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s11664-012-2351-8 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Sadiq Muhammad George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, 801 Ferst Drive NW, 30332, Atlanta, GA, USA aut NATIONALLICENCE 700 1- Pesci Raphaël ENSAM-Arts et Métiers ParisTech, LEM3 UMR CNRS 7239, 4 rue Augustin Fresnel, 57078, Metz, France aut NATIONALLICENCE 700 1- Cherkaoui Mohammed George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, 801 Ferst Drive NW, 30332, Atlanta, GA, USA aut NATIONALLICENCE 773 0- Journal of Electronic Materials Springer US; http://www.springer-ny.com 42/3(2013-03-01), 492-501 0361-5235 42:3<492 2013 42 11664 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer