Structurally Stabilizing and Environment Friendly Triggers: Double‐Metallic Lead‐Free Perovskites

Solar RRL ◽  
2019 ◽  
Vol 3 (9) ◽  
pp. 1900148 ◽  
Author(s):  
Hang Yin ◽  
Yeming Xian ◽  
Yongli Zhang ◽  
Wenzhe Li ◽  
Jiandong Fan
Keyword(s):  
Lead Free ◽  
Environment Friendly ◽  
Metallic Lead

Kinetics-Based Modeling of Bond-Metal Dissolution and IMC During Soldering

2006 ◽  
Author(s):  
Mohammad Faizan ◽  
Guo-X. Wang
Keyword(s):  
Intermetallic Phase ◽  
Molten Solder ◽  
Lead Free ◽  
Joint Interface ◽  
Environment Friendly ◽  
Soldering Process ◽  
Substrate Dissolution ◽  
Soldering Reaction ◽  
Lead Free Solders ◽  
Kinetics Of

Soldering has become an indispensable joining process in the electronic packaging industry. The industry is aiming for the use of environment friendly lead-free solders. All the lead-free solders are high tin-containing alloys. During the soldering process, an intense interaction of metallization on PCB and tin from the solder occurs at the metallization/solder interface. Intermetallic compound (IMC) is formed at the interface and subsequently PCB bond-metal (substrate) is dissolved into the molten solder. In the present study the terms bond-metal and substrate will be used interchangeably and the term 'substrate' refers to the top layer of the PCB which comes in contact with the molten solder during soldering reaction. Thickness of the intermetallic phase formed at the joint interface and amount of substrate lost is critical in achieving reliable solder joints. During the wet phase of soldering process, the IMC does not grow as layered structure; rather it takes the shape of scallops. The growth of scalloped IMC during the solder/substrate interaction entails complicated physics. Understanding of the actual kinetics involved in the formation of IMC phase is important in controlling the process to achieve desired results. This paper presents theoretical analysis of the kinetics involved in the formation of the scalloped intermetallic phase. The intermetallic phase growth is experimentally investigated to support the underlying kinetics of the process. Numerical model has been suggested to translate the physics of the process. The model is based on the basic mass diffusion equations and can predict the substrate dissolution and IMC thickness as a function of soldering time.

Study on the Lead-Free Easy-Cutting Mg-Sb Brass

2011 ◽  
Vol 239-242 ◽  
pp. 1670-1673 ◽  
Author(s):  
Lei Li ◽  
Biao Ma ◽  
Qiang Li ◽  
Guo Jie Huang
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Grain Boundaries ◽  
Human Health ◽  
Hot Working ◽  
Experimental Results ◽  
Lead Free ◽  
Environment Friendly ◽  
Working Property ◽  
Pipe Joint

Traditional lead brass is gradually prevented from application by many countries’ governments because lead does harm to human health and pollutes the environment. New types of environment-friendly lead-free brass with favorable machinability are urgently demanded in the electrical, electronics and plumping fields. Lead-free Mg-Sb brass was fabricated in present. Experimental results showed that when the content of Mg is 1.0wt%, Sb is 0.8wt% and Cu is 58.0~59.0wt%, the alloy’s mechanical properties and machinability are favorable for industry application. With the increase of the content of Sb, the machinability increased, while the mechanical properties decreased. Lots of Cu2Mg and Cu9Sb2 particles on the order of microns exist in the inner-grain and grain boundaries. These particles improve the machinability, however, lower the tensile strength and the elongation. A three-way pipe joint was successfully punched with the fabricated Mg-Sb brass bar, and this demonstrated that the fabricated Mg-Sb brass possesses favorable hot working property.

A distinct mutual phase transition in a new PVDF based lead-free composite film with enhanced dielectric and energy storage performance and low loss

2017 ◽  
Vol 5 (10) ◽  
pp. 2531-2541 ◽  
Author(s):  
Dong Guo ◽  
Kai Cai ◽  
Yunli Wang
Keyword(s):  
Phase Transition ◽  
Energy Storage ◽  
Polyvinylidene Fluoride ◽  
Composite Films ◽  
Lead Free ◽  
Low Loss ◽  
Ceramic Filler ◽  
Environment Friendly ◽  
High Permittivity ◽  
Storage Performance

Environment-friendly polyvinylidene fluoride (PVDF) based composite films were fabricated by using a high permittivity lead-free Ba(Sn,Ti)O3–(Ba,Ca)TiO3 (BCTS) ceramic filler with a special ‘tricritical’ phase structure.

Effects of La2O3 on the Piezoelectric Properties of Lead-Free (Bi0.5Na0.5)0.94Ba0.06TiO3 Piezoelectric Ceramics

2006 ◽  
Vol 510-511 ◽  
pp. 538-541 ◽  
Author(s):  
Y.-J. Son ◽  
Y.G. Choi ◽  
Joon Chul Kwon ◽  
K.W. Cho ◽  
Young Moon Kim ◽  
...  
Keyword(s):  
Dielectric Properties ◽  
Sintered Density ◽  
Piezoelectric Properties ◽  
Lead Free ◽  
Environment Friendly ◽  
Bulk Ceramic ◽  
System A ◽  
Maximum Value ◽  
Doping Effects ◽  
Dielectric And Piezoelectric Properties

In an approach to acclimate ourselves to the recent ecological consciousness trends, a lead free piezoelectric material, bismuth sodium barium titanate (Bi0.5Na0.5)0.94Ba0.06TiO3 (BNBT), was considered as an environment-friendly alternative to the PZT system. A perovskite BNBT was synthesized by the conventional bulk ceramic processing technique.La2O3 as a dopant was incorporated into the BNBT system up to 0.025 mol, and the doping effects on subsequent piezoelectric and dielectric properties were systematically investigated. In the case of La2O3 addition, the formation of grain boundary coherency was remarkably increased, and the sintered density was increased with increasing La2O3 contents. Piezoelectric and dielectric properties were shown to have the maximum value at 0.02 mol of La2O3 addition. La3+ ions were believed to act as a softener in the BNBT system and to enhance dielectric and piezoelectric properties in this study.

scholarly journals Enhanced Electrical Properties of Lead-Free Piezoelectric KNLN-BZ-BNT Ceramics With the Modification of Sm3+ Ions

2021 ◽  
Vol 8 ◽  
Author(s):  
Yi Quan ◽  
Lingyan Wang ◽  
Wei Ren ◽  
Jinyan Zhao ◽  
Jian Zhuang ◽  
...  
Keyword(s):  
Thermal Stability ◽  
High Temperature ◽  
Electrical Properties ◽  
Piezoelectric Properties ◽  
Piezoelectric Ceramics ◽  
High Thermal Stability ◽  
Lead Free ◽  
Environment Friendly ◽  
Good Thermal Stability ◽  
Good For

Environment-friendly lead-free piezoelectric ceramics with great properties and high thermal stability are desired in the industry. In this work, the Sm3+-modified lead-free 0.915(K0.45Na0.5Li0.05)NbO3–0.075BaZrO3–0.01(Bi0.5Na0.5)TiO3 (KNLN-BZ-BNT) ceramics are prepared. The piezoelectric properties are improved with the introduction of Sm3+, and the optimal properties (d33 = 325 pC/N and d33* = 384 pm/V) are achieved in the ceramic modified with 0.3 mol% Sm3+ ions. Meanwhile, this sample shows good thermal stability such that the values of d33* decreased less than 20% when the temperature raised from 30 to 180oC. These results show the Sm3+-modified KNLN-BZ-BNT ceramics are good for further applications even under high temperature.

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