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Tzu-Yang Chiang, Yong-Chi Chang, Chao-Hong Wang, Andromeda Dwi Laksono and Yee-Wen Yen

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Metals 2023, 13(4), 710

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https://doi.org/10.3390/met13040710
 

Abstract
  The CoCuFeNi high entropy alloy (HEA) has excellent electrical, thermal, and mechanical properties. In electronic packaging technology, Sn is the major element of lead-free solders. In this study, we used the CoCuFeNi HEA as the substrate and Sn as the solder and investigated the liquid/solid interfacial reactions of the Sn/CoCuFeNi system at 300, 375, and 450 °C for 30, 60, 100, 150, 360, and 480 min. The results indicated that the (Fe, Co)Sn2 phase was formed in the Sn/CoCuFeNi couples for all various reaction temperatures and at different durations. Additionally, the (Co, Ni)Sn2 phase was precipitated at the solder side and near the (Fe, Co)Sn2 phase when the reaction time increased. The thickness of the (Fe, Co)Sn2 phase increased with the increase in reaction temperature and time, and it was proportional to the square root of the reaction time. Overall, our results showed that the growth mechanism of the (Fe, Co)Sn2 phase was diffusion-controlled in the Sn/CoCuFeNi couples.

Keywords: CoCuFeNi high entropy alloy; lead-free solder; Sn/CoCuFeNi couple; liquid/solid interfacial reaction; diffusion-controlled

Andromeda Dwi Laksono, Tzu-Yang Tsai, Tai-Hsuan Chung, Yong-Chi Chang and Yee-Wen Yen 

 

Metals 2023, 13(1), 12

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https://doi.org/10.3390/met13010012

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Abstract
  Cu-based alloys are one of the most promising substrates to enhance the performance of lead-frame materials. In the present study, the interfacial reactions in the Sn-0.7 wt.% Cu (SC) lead-free solder reacting with Cu-3.3 wt.% Fe (C194), Cu-2.0 wt.% Be (Alloy 25), and Cu-3.3 wt.% Ti (C1990 HP) were investigated. The material underwent a liquid–solid interface reaction, and the reaction time was 0.5 to a few hours at the reaction temperatures of 240 °C, 255 °C, and 270 °C. The morphology, composition, growth rate, and growth mechanism of the intermetallic compounds (IMCs) formed at the interface were investigated in this study. The results showed that the reaction couples of SC/C194, SC/Alloy 25, and SC/C1990 HP formed IMCs, which were the [(Cu, Fe)6Sn5 and (Cu, Fe)3Sn], [(Cu, Be)3Sn and (Cu, Be)6Sn5], and [Cu6Sn5] phases, respectively. Finally, the IMC growth mechanism for the SC/C194, SC/Alloy 25, and SC/C1990 HP couples displayed reaction control, grain boundary diffusion control, and diffusion control, respectively.

Keywords: interfacial reaction; Sn-0.7 wt.% Cu (SC) lead-free solder; C194; Alloy 25; C1990 HP

Po-Cheng Kuo, Sin-Yi Chen ,William Yu, Ryo Okumura, Satoshi Iikubo, Andromeda Dwi Laksono, Yee-Wen Yen ,and Alberto S. Pasana 

 

Materials 2022, 15(9), 3098

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https://doi.org/10.3390/ma15093098

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Abstract
  In recent years, high-entropy alloys (HEAs) that contain fine grains of intermetallic compounds (IMCs) have gained increasing attention as they have been shown to exhibit both high mechanical strength and strong corrosion resistance. One such class of HEAs is that of CuFeTiZrNi alloys. In this study, we have investigated the effect of increasing Ni content on the microstructure, hardness, and corrosion resistance of the CuFeTiZrNix alloys (where x = 0.1, 0.3, 0.5, 0.8, 1.0 in a molar ratio). The alloys used in this study were prepared in an arc melting furnace and then annealed at 900 °C. First-principles calculations of the bulk modulus were also performed for each alloy. The results revealed that increasing the Ni content had several effects. Firstly, the microstructure of the CuFeTiZrNix alloys changed from B2_BCC and Laves_C14 in the CuFeTiZrNi0.1 and CuFeTiZrNi0.3 alloys to FCC, B2_BCC, and Laves_C14 in the CuFeTiZrNi0.5 alloys; and to FCC, B2_BCC, Cu51Zr14, and Laves_C14 in the CuFeTiZrNi0.8 and CuFeTiZrNi1.0 alloys. Secondly, IMCs arising from a combination of the refractory elements (Ti and Zr) and atomic size differences were found in the interdendritic region. Thirdly, as the Ni content in the CuFeTiZrNix alloys increased, the hardness decreased, but the corrosion resistance increased.

Keywords: CuFeTiZrNix alloys; microstructure; hardness; corrosion resistance; first-principles calculations

2022

1. Andromeda Dwi Laksono, Jing-Ting Chou, Tzu-Yang Chiang, Yee-Wen Yen

"Study on Interfacial Reactions and Tensile Properties in the Sn/C1990 HP Systems"

2. Chiao-Yi Yang, Andromeda Dwi Laksono, Yee-Wen Yen, Yi-Zhen Guo, Chu-Hsuan Wang, Jia-Lin Li, Tzu-Yang Chiang"Investigation of phase equilibria of the Au–Ni–Sn ternary system and interfacial reactions in the Au/Sn/Ni/Cu multilayer couple"

3. Andi Idhil Ismail, Andromeda Dwi Laksono,Hizkia Dewanto,Nabila Amalia Putri,Yee-wen Yen "Effect of reflow temperature on intermetallic compound thickness for Sn-58Bi/Cu reaction couple"

4. Chiao-Yi Yang,Yee-wen Yen,Yi-Zhen Guo,Chu-Hsuan Wang,Jia-Lin Li,Tzu-Yang Chiang"Investigation of Phase Equilibria of the Au-Ni-Sn Ternary System and Interfacial Reactions in the Au/Sn/Ni/Cu Multilayer Couple"

2021

1. Yu-Chun Li, Ching-Hsun Chang, Alberto S. Pasana, Hsien-Ming Hsiao, Yee-wen Yen"Interfacial Reactions in Lead-Free Solder/Cu-2.0Be (Alloy 25) Couples"

2020

1. Sagung Dewi Kencana, Yu-Lin Kuo, Clarissa Changraini,Yee-wen Yen,Eckart Schellkes,Wallace Hsin-Yi Chuang"Atmospheric Pressure Plasma Surface Treatment for Solderability Enhancement on Printed Circuit Boards"

2. Gita Novian Hermana,Hsien-Ming Hsiao,Po-Cheng Kuo,Peter K Liaw,Yu-Chun Li,S. Iikubo Yee-wen Yen "Phase equilibria of the Cu-Zr-Ti ternary system at 703°C and the thermodynamic assessment and metallic glass region prediction of the Cu- Zr-Ti ternary system"

3. Chia-Yu Liu,Po-Cheng Kuo,Chih-Ming Chen,jia-ying Dai,Yee-wen Yen,Alberto S. Pasana "Effect of Multiple Reflowing Processes on Interfacial Reactions and Mechanical Properties between Sn-9.0 wt.%Zn, Sn-3.0 wt.%Ag-0.5 wt.%Cu Solders and Ag Substrate"

2019

1. Chia-Yu Liu, Po-Cheng Kuo, Chih-Ming Chen, Jia-Ying Dai, Yee-Wen Yen & Alberto S.Pasana "Effect of Multiple Reflowing Processes on Interfacial Reactions and Mechanical Properties between Sn-9.0 wt.%Zn, Sn-3.0 wt.%Ag-0.5 wt.%Cu Solders and Ag Substrate"

2. Yee-Wen Yen, Hsien-Ming Hsiao, Kuo-Jung Chen, Yi-Show Lin & Mei-Ting Lai "Interfacial Reactions Between Lead-Free Solders and Ni-Pd-Co Alloys"

3.  Andromeda Dwi Laksono*, Jing Shiun Chang, Jessie Yan, Yee Wen Yen"Interfacial Reaction between Sn and Cu-Ti Alloy (C1990 HP)"

2018

1. Yee-Wen Yen, William Yu, Chu-Hsuan Wang, Chih-Ming Chen, Yu-Chun Li, Pei-Yu Chen & Guan-Da Chen "Study of Interfacial Reactions Between Lead-Free Solders and Cu-xZn Alloys"

2. Hsien-Ming Hsiao, Yung-Chin Lan, Gita Novian Hermana, Hao Chen & Yee-Wen Yen MRS Communications"Investigation of the phase equilibria at 773 K and metallic glass regions in the Ag-Al-Zr ternary system"

2017

1. Gita Novian Hermana, Tzu-Ting Huang, Chih-Ming Chen, Chin-Hung Lin, Satoshi Iikubo, Yee-Wen Yen"Phase equilibria of the Cu-Ni-Zr ternary systems at 800 °C and thermodynamic assessment and metallic glass region prediction for the Cu-Ni-Zr ternary system"

2. Yee-Wen Yen , Chung-Yung Lin, Gita Novian Hermana , Pei-Yu Chen a, Yi-Pin Wu"Interfacial reactions in the Au/Sn-xZn/Cu sandwich couples"

3. Yee-Wen Yen; Pei-Yu Chen; Guan-Da Chen"Interfacial reactions between lead-free solders and Cu-40Zn alloys"

2016

1. Hsien-Ming Hsiao, Song-Mao Liang, Rainer Schmid-Fetzer, Yee-wen Yen"Thermodynamic assessment of the Ag-Zr and Cu-Zr binary systems"

2. Gita Novian Hermana; Yen-Wei Chang; Pei-Yu Chen; Chao-Wei Chiu; Yee-wen Yen"Phase equilibria of the Sn-Ni-W ternary system at 750 °C"

3. Tzu-Ting Huang, Shih-Wei Lin, Chih-Ming Chen, Pei Yu Chen & Yee-Wen Yen"Phase Equilibria of the Fe-Ni-Sn Ternary System at 270°C"

4. Hsien-Ming Hsiao , Yen-Wei Chang , Chih-Ming Chen , Pei-Yu Chen , Yi-Pin Wu and Yee-Wen Yen"Phase equilibria in the Au–Bi–Sn ternary system at temperatures of 80, 125, and 150 °C"

5. Hsing-Ting Chan , Chih-Fan Lin , Yee-Wen Yen , Chih-Ming Chen"Effects of current stressing on the p-Bi2Te3/Sn interfacial reactions"

2015

1. Yee-Wen Yen, Chung-Yung Lin, Mei-Ting Lai & Wan-Ching Chen"Interfacial Reactions in the Ni/Sn-xZn/Cu Sandwich Couples"

2. Yee-wen Yen, Hsien-Ming Hsiao, Pei-Sheng Shao & Yen Wei Chang "A Novel Electronic Packaging Method to Replace High-Temperature Sn-Pb Solders"

2014

1. Yee-Wen Yen, Chao-Wei Chiu, Chih-Ming Chen, Mei-Ting Lai & Jia-Ying Dai "Interfacial Reactions in Sn/Ni-xW Couples"

​2. Chi-Pu Lin , Chih-Ming Chen , Yee-Wen Yen "Enhanced growth of the Cu6Sn5 phase in the Sn/Ag/Cu and Sn/Cu multilayers subjected to applied strain"

3. Yee-Wen Yen , Ruo-Syun Syu , Chih-Ming Chen , Chien-Chung Jao , Guan-Da Chen "Interfacial reactions of Sn–58Bi and Sn–0.7Cu lead-free solders with Alloy 42 substrate"

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