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An evaluation of Sn-Cu-Ga and Sn-Cu-Ag solder alloys for applications within the electronics industry Georgiana Melcioiu1a, Viorel-Aurel Şerban1b, Mark Ashworth2c, Cosmin Codrean 1d, Marin Liţă1e, Geoffrey Wilcox2f 1 ‘’Politehnica’’ University of Timişoara 2 Department of Materials, Loughborough University, Loughborough, Leicestershire, UK, LE11 3TU ageorgianamelcioiu@yahoo.com, bviorel.serban@rectorat.upt.ro, cM.A.Ashworth@lboro.ac.uk, dcosmin.codrean@mec.upt.ro, emarin.lita@mec.upt.ro, fG.D.Wilcox@lboro.ac.uk, Key words: tin whiskers, PCB, printed circuit boards, melt spinning, solder, ribbons ABSTRACT Components soldered with Sn-based alloys are susceptible to the growth of whiskers.
The choice of solder alloy could be influenced by factors such as: substrate material used (e.g. brass or copper), the residual stresses within the substrate (copper-plating, immersion plating), composition and properties of intermetallic compounds formed and the diffusion of alloying elements within the tin.
Whisker growth on the solder alloy could be influenced by: the shape and size of the tin grains, the grain orientation of the tin, the thickness of solder layer, tin oxide formation, tensile stresses generated within the soldering material, elemental diffusion and the development of a columnar grain structure.
The material is melted by induction heating in a quartz crucible and is ejected, under pressure, through an aperture in base of the crucible onto a copper roller.
ACKNOWLEDGMENT This work was partially supported by the strategic grant POSDRU/CPP107/DMI1.5/S/77265, Project ID77265 (2010), co-financed by the European Social Fund – Investing in People, within the Sectoral Operational Programme Human Resources Development 2007 – 2013 REFERENCES [1] Suganuma K., 2004 Lead-free soldering in electronics science,tehnology and enviromental impact, Marcel Dekker, , ISBN:0824741021(pp.170-190) [2] Brusse J., Leidecker H., (2010), Tin Whiskers NASA Goddard, (pp 7-15),(http://nepp.nasa.gov/WHISKER/) [3] Brusse J., Leidecker H., Panashchenko L. 2010, Metal Whiskers A Discussion of Risks and Mitigation, Enviromental Technology Technical Symposium and Workshop Thesis, University of MD (http://nepp.nasa.gov/whisker) (pp. 3-15) [4] Şerban V.A., Codrean C, D Uţu and C Opriş, 2009, Amorphous alloys for brazing copper based alloys The 13th International Conference on Rapidly Quenched and Metastable Materials, Journal of Physics, ISBN. 1742-6596 Journal

Experiment 1.1 Experimental materials and pretreatment Thlaspi caerulescens L. rich in selenium is collected from Yu Tangba of Enshi, Hubei Province, while the normal thlaspi caerulescens L. is collected from the mountain behind Hubei Institute for Nationalities.
Seen from Figure 2, both thlaspi caerulescens L. and selenium thlaspi caerulescens L.in thlaspi caerulescens L. have clear role of scavenging O2-•, and from 60s-180s, the scavenging capacity and the amount the samples form a certain linear relationship, with the capacity enhancing with the increasing of the amount of materials.
FOOD SCIENCE,2008,29(8):100-102 [2] Shu-xun shao,Bao-shan zheng, su Hong can.A NEW SPECIES OF SELENIUM HYPERACCUMULATOR IDENTIFIED IN YUTANGBA SE DEPOSIT AREA[J].
JOURNAL OF SOUTHWEST FORESTRY COLLEGE,2011,31(1):31-33 [4] ZENG Jun, SHI Guo-rong, ZHANG Xiang-yuan.
JOURNAL OF HUNAN AGRICULTURAL UNIVERSITY, 2009.35(3): 295-298 [5] Shaohua han, Jingbo zhu, Yanyan wang.

Thereby, further research and development of Cu based SMAs are expected to obtain alternative SME materials.
After weighing source materials of Cu, Sn, and Mn in 3N level, we made nine alloy ingots using a high-frequency induction melting furnace in air with N2 gas injection.
[3] Kainema R, Ohmori T, Sudo Y, Ishida K, Journal of Japan institute of copper, 54, (2015), 1, pp. 1 to 5
[4] Nakajima T, Muramatsu N, Sasaki Y, Kaneko D, Takeda M, Journal of Japan institute of copper, 56, (2017), 1, pp. 266 to 270
[5] Miura S, Kato H, Summary of The Society of materials science, Japan, 37, 71-73, 1988-05-26 [6] N.

Unlike normal strength concrete, high strength high performance concrete (HPC) behaves more like an ideal composite material.
The water-cementitious material ratio (w/cm) is 0.38.
Acknowledgements This work was financially supported by the National Science Council, Taiwan under Grant No.
Lai, ACI Materials Journal, Vol. 104 (2007), p. 344
Hsiao, Journal of the Chinese Institute of Engineers, Vol. 20 (1997), p. 661

Soong, Random differential equations in science and engineering, Academic Press, (1973) [2] J.
Zani, Masonry-like materials with bounded shear stresses European J.
[9] Lucchesi, M., Pintucchi, B., A numerical model for non-linear dynamics analysis of masonry slender structures, European Journal of Mechanics A/Solids, 26, (2007), 88-105
European Journal of Mechanics /A Solids, 59, (2016) 210-231
Zani, Dynamic analysis of FRP-reinforced masonry arches via a no-tension model with damage, Key Engineering Materials, (2015)

., Ltd of WISCO, Wuhan 430083, P R China; 2School of Materials Science and Engineering of WHUT, Wuhan 430070, P R China aluther@wisco.com.cn, b783911530@qq.com, cfanxm@whut.edu.cn, d373014011@qq.com * Corresponding Author Keywords: Cast Copper Stave; Numerical Simulation; ProCAST; Process Optimization Abstract.
The body material is pure copper(WCu≧99.5%).
(3)materials Mould: resin sand; casting: pure copper; tube: steel(25# carbon steel).
Model of forming-accretion on blast furnace copper stave and industrial application, Journal of Iron and Steel Research, 7(2012)1-5
Serajzadeh, et al, Simulation of melt flow in coated mould cavity in the casting process, Journal of Materials Processing Technology,42(2003)493-507

The application of composite materials in the framework of aerospace structures has been growing up due to high stiffness and strength-to-weight ratios but also to the path-loads management capability [1].
The analyzed configuration consists of cross-ply graphite-epoxy stack while PZT-5A material is used to arrange the sensing device.
Milazzo, Multidomain boundary integral formulation for piezoelectric materials fracture mechanics, International Journal of Solids and Structures 38 2001 7065-70782001
Orlando, Global/Local FEM-BEM Stress Analysis of Damaged Aircraft Structures, CMES: Computer Modeling in Engineering and Sciences, 36(1) 2008 23-41
[10] S.Narayan, and J.Beuth, Designation of mode mix in orthotropic composite delamination problems, International Journal of Fracture 90 1998 383-400

Fly ash has been used as additive material in cement and concrete for long time [3].
Materials and methods 1.1 Materials and characterization Fly ash used in this study obtained from Hefei power plant, which was modified with sodium hydroxide in ceramic pot.
Alkali activated fly ash is an economic material for the removal of dyes.
Acknowledgments This work was financially supported by National Science and Technology Support Program of China (No. 2012BAC14B00).
Chemical Engineering Journal.Vol. 150(2009), p. 352.

So the end of eccentric impacts crashing the granular materials in container.The dynamics model in vibration-impact crushing system of a unilateral single-mass is showed in Fig. 2.
When the displacement exceeds the clearance, , the mass m impacted on granular materials. 3 Vibration differential equations Based on the static balance position as its origin, x as coordinate, a coordinate was built.
When is greater than 35mm, the mass m does not come into contacting with granular materials.
The cleareance among materials and crushing plates is limited to smaller value.
Journal of Vibration and Shock, 2000, 19(3)：34-36(In Chinese) [3] Walter Lacarbonara, Fabrizio Vestroni.

Determination of Ignition Temperature of Organic Dust Layers Turekova Ivana 1,a, Turnova Zuzana 2,b , Harangozo Jozef 3,c, Kasalova Ivana 4,d and Chrebet Tomas5,e 1,2,3,4 Slovak University of Technology in Bratislava, Faculty of Materials Science and Technology in Trnava, Department of Safety Engineering, Paulinska 16, 91724 Trnava, Slovak Republic aivana.turekova@stuba.sk, bzuzana.turnova@stuba.sk, cjozef.harangozo@stuba.sk, divana.kasalova@stuba.sk, etomas.chrebet@stuba.sk Keywords: minimum ignition temperature, dust layer, fire characteristics Abstract.
This fact has a base in the thermal conductivity of materials.
It depends on the composition and structure of the material, its porosity, humidity, layer stratification and temperature that conducts heat.
Journal of Loss Prevention in the Process Industries 13 (2000) 183–199.
Methods for determining the minimum ignition temperatures of dust [4] TUREKOVÁ, I: Study of high-temperature degradation by lignocelulose materials. - 1st ed. - Dresden : Forschungszentrum Dresden - Rossendorf, 2009. - 130 p. - (Scientific monographs). - ISBN 978-3-941405-08-0 [5] TUREKOVÁ, I., SLABÁ, I., DUCHOŇ, M.