Effects of Sn addition on phase formation and mechanical properties of TiCu-based bulk metallic glass composites

Effects of Sn addition on phase formation and mechanical properties of TiCu-based bulk metallic glass composites:

Highlights
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Effects of Sn on mechanical properties of TiCu-based BMG composites were studied.
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Formation of brittle CuTi2 and ZrTiCu2 intermetallic compounds were suppressed.
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Excessive Sn addition deteriorated glass forming ability.
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Large plasticity and strong work-hardening in the BMG composites were obtained.
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Related mechanisms for the enhanced properties were discussed.
Abstract
A unique combination of macroscopic properties including high strength, large plasticity and strong work-hardening behavior was realized in TiCu-based bulk metallic glass (BMG) composite with proper addition of Sn. It was found that proper addition of Sn induced formation of BMG composites consisting of a single B2-TiCu phase via suppressing precipitation of the brittle CuTi2 and ZrTiCu2 intermetallic compounds. With excessive Sn addition, however, glass forming ability of the resultant alloys was severely decreased due to formation of additional Zr5Sn3 phase. Moreover, desirable elastic mismatch (e.g., Young's modulus and hardness) between the reinforcing crystalline phase and amorphous matrix, resulted from the Sn addition, remarkably accommodated large plasticity and strong work-hardening capability of the current BMG composites.

http://www.sciencedirect.com/science/article/pii/S0966979513001477

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Synthesis of Cu2ZnSnS4 films from co-electrodeposited Cu-Zn-Sn precursors and their microstructural and optical properties

Synthesis of Cu2ZnSnS4 films from co-electrodeposited Cu-Zn-Sn precursors and their microstructural and optical properties:

Highlights
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A novel electrolyte formula and co-electrodeposition parameters are presented.
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The CZTS films are prepared from co-electrodeposited precursors.
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CZTS film forms by reaction among binary and ternary sulfides at high temp.
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Photoluminescence was obtained from prepared CZTS films at 550 °C for 1 h.
Abstract
The Cu2ZnSnS4 (CZTS) films were successfully prepared using a process of co-electro-deposition of Cu-Sn-Zn precursors by a novel electrolyte formula and optimized parameters on Mo substrates, succeeded by annealing in saturated sulfur atmosphere. The optimized electrolyte formula was achieved as 0.16 M CuSO4·5H2O, 0.33 M ZnSO4, 0.08 M SnCl2·2H2O, 2.25 M NaOH, 1.36 M C6H5Na3O7 and 1.00 M C4H6O6 under a voltage of -1.62 V for 5 min. Cu3Sn, Cu6Sn5 and Cu4Zn alloys were firstly synthesized at temperature lower than 300 °C. At 300 °C, these alloys decomposed in sulfur atmosphere and CuS, SnS and ZnS binary phases were formed. Ternary Cu4SnS6 formed through reaction between CuS and SnS above 350 °C. Finally, the CZTS films were synthesized through reaction among CuS, SnS, ZnS and Cu4SnS6 sulfides. CZTS films synthesized at 550 °C for 1 h had an average atomic ratio of 0.96 and 1.1 for Cu/(Zn + Sn) and Zn/Sn, respectively. The photoluminescence peaking at about 1.55 eV in the prepared samples demonstrated a high quality of the CZTS film.

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