ree-Cutting Aluminium Alloys with Tin as Substitution for Lead

SpringerLink Over the past three decades, there has been an ever increasing global movement to eliminate lead and lead containing products due to their toxicity. Consequently, by the 1st of July, 2008, aluminium for machining purposes with a lead content of more than 0.4 wt.-% by weight will be prohibited by the European Union (End of Life Vehicles Directive). The aim of the investigations of the Institute of Nonferrous Metallurgy at the University of Leoben is the development of a lead-free aluminium alloy with good free-cutting machinability without a cut back in productivity and performance in end uses as well as applications. Compared to commercial trade alloys containing lead, those new ones with tin have to have similar or even better properties referring to microstructure, mechanical criteria, corrosion resistance and machinability. Grade "A" machinability performance – short and broken chips – is strived for in order to guarantee high tool feed rates and spindle speeds in connection with low cycle times and reduced machine downtimes for cleaning. Similar to the behaviour of lead, the formation of suitable chips of tin-alloyed 2030 aluminium alloy depends on the influence of inclusions on rupture mechanisms during machining. Chip breaking inclusions of tin reduce – together with other impurity and alloying elements – the cohesion of crystal grains.

Development of non-leaded free-cutting steel by adding tin

Scopus: "A type of non-leaded free cutting steel was developed by adding tin into steel melt. Machining tests and mechanical tests of the steel were conducted. The results showed that tin would improve the machinability of the steel when the tin content in the steel was less than 0.05%, and any negative influence was not found on the mechanical properties of the steel."

Li, L.a , Zhu, R.a , Guo, H.a , Dong, J.b , Li, F.b

a Metall. Eng. Sch., Univ. of Sci. and Technol. Beijing, Beijing 100083, China

b Technol. Ctr., Laiwu Iron and Steel Co. Ltd., Laiwu 271104, China

Russia to zero out tax on Far Eastern tin miners for five years - Putin

Factiva: "The zero tax on tin mining in Far Eastern Russia would be a temporary concession, lasting five years, Prime Minister Vladimir Putin said at Tuesday's government meeting.

'The tax break is a temporary one, for five years. And we expect it will revive not only tin mining but also a number of settlements in remote districts of Yakutia and the Khabarovsk territory,' Putin said.

The measure, announced on December 6, should come into force in 2011 and create 2,500 jobs, he said."

Better batteries from the bottom up

nanomagazine: "Rice University researchers have moved a step closer to creating robust, three-dimensional microbatteries that would charge faster and hold other advantages over conventional lithium-ion batteries. They could power new generations of remote sensors, display screens, smart cards, flexible electronics and biomedical devices.

The batteries employ vertical arrays of nickel-tin nanowires perfectly encased in PMMA, a widely used polymer best known as Plexiglas. The Rice laboratory of Pulickel Ajayan found a way to reliably coat single nanowires with a smooth layer of a PMMA-based gel electrolyte that insulates the wires from the counter electrode while allowing ions to pass through."

They feel the PMMA coating will increase the number of times a battery can be charged by stabilizing conditions between the nanowires and liquid electrolyte, which tend to break down over time.

The team is also studying how cycling affects nanowires that, like silicon electrodes, expand and contract as lithium ions come and go. Electron microscope images of nanowires taken after many charge/discharge cycles showed no breaks in the PMMA casing -- not even pinholes. This led the researchers to believe the coating withstands the volume expansion in the electrode, which could increase the batteries' lifespans.

Tin prices may hit at USD 30000 per tonne in 2011

Steel Guru: "Reuters reported that tin prices could potentially hit record highs at around USD 30,000 per tonne next year before falling sharply back as producer’s ramp up output.

Consumer goods group Henkel said that propelled higher by worries about falling supplies from the world's top exporter Indonesia, tin on the London Metal Exchange reached a record high of USD 27,500 per tonne in early November."

Comparative study of composite electrodes containing tin, polyacrylonitrile and cobalt or iron

ScienceDirect Composite materials containing Co–Sn alloys and polyacrylonitrile (PAN) have been prepared by reduction of Co(II) and Sn(II) in dimethylformamide with NaBH4. The resulting cobalt and tin form an amorphous alloy and the PAN molecules hinder the growth and crystallization of the metallic grains. After heating the composite material obtained at 300 °C in Ar-atmosphere, the amorphous alloy leads to poorly crystallized CoSn2, and the PAN molecules are partially pyrolyzed. In contrast, the reduction of Fe(II) and Sn(II) leads to crystalline Sn. The electrode containing nanosized CoSn2 and PAN shows an excellent electrochemical behavior in lithium cells due to the structural stability of the PAN matrix and the small size of the metallic grains


Francisco Nacimientoa, Ricardo Alcántara, a,  and José L. Tiradoa
a Laboratorio de Química Inorgánica, Universidad de Córdoba, Edificio C3, Planta 1, Campus de Rabanales, 14071 Córdoba, Spain
Received 30 July 2010;  revised 21 September 2010;  accepted 7 November 2010.  Available online 12 November 2010. 

Three-dimensional nanocarbon and the electrochemistry of nanocarbon/tin oxide for lithium ion batteries

Scopus: "In this work, the potential of using coconut shell, which is very cheap and readily available, for the production of graphitic nanocarbon three-dimensional networks is investigated. The three-dimensional carbon has been produced via the wet-impregnation of coconut shell powder with a transition metal catalyst. The novel process employed offers low costs and environmental advantages, with biological waste used in place of carbonaceous precursor as the feedstock.

Nanocarbon/tin oxide composites were prepared via wet-impregnation and the solvothermal method, using tin chloride solution with the activated nanocarbon. The electrochemical performances of the three-dimensional nanocarbon doped with tin oxide and of activated nanocarbon alone as anode materials were investigated in rechargeable lithium ion batteries. One composite made by using the solvothermal method shows stable cyclic retention up to 100 cycles and delivers a high reversible capacity of about 405�mAh g-1"

Zhang, C.a b , Quince, M.a , Chen, Z.a , Guo, Z.a b , Liu, H.b

a School of Mechanical, Materials and Mechatronics Engineering, University of Wollongong, Wollongong, 2522, Australia

b Institute for Superconducting and Electronic Materials, University of Wollongong, Wollongong, 2522, Australia

Improvement of the performance of inverted polymer solar cells with a fluorine-doped tin oxide electrode

Scopus: "We prepared the inverted polymer solar cells (PSCs) with a fluorine-doped tin oxide (FTO) as a transparent electrode and with TiO2, WO3 and WOx as selective charge transport layers. An adequately thick TiO2 nanoparticles layer was employed for covering a very rough FTO surface. Using a solution-based WOx film instead of a vacuum deposited WO3 layer in inverted polymer solar cells showed comparable device performance. A self-assembled molecular (SAM) layer of PCBA and N719 on top of TiO2 improves the device performance by reducing the series resistance at the interface between the active layer and the TiO2 film. The power conversion efficiency (PCE) was improved by 16%, especially in the case of [6,6]-phenyl-C61-butyric acid (PCBA)"

Scientists Create World's Smallest Battery

Neatorama: "A research team by Jianyu Huang (pictured) at Sandia National Laboratories in Albuquerque claims to have developed the world’s smallest battery:

It consists of a bulk lithium cobalt cathode three millimeters long, an ionic liquid electrolyte, and has as its anode a single tin oxide (Sn02) nanowire 10 nanometers long and 100 nanometers in diameter – that’s one seven-thousandth the thickness of a human hair.

The battery was made inside a transmission electron microscope, allowing the scientists to study it while it was charging:

By following the progression of the lithium ions as they travel along the nanowire, the researchers found that during charging the tin oxide nanowire rod nearly doubles in length. This is far more than its diameter increases and could help avoid short circuits that may shorten battery life. This unexpected finding goes against the common belief of workers in the field that batteries swell across their diameter, not longitudinally."

One-step synthesis of carbon-coated tin dioxide nanoparticles for high lithium storage

Scopus: "Carbon-coated SnO2 nanoparticles were synthesized by a simple one-pot hydrothermal treatment. During the hydrothermal process, SnO2 was formed by the hydrolysis of tin(II) dichloride dihydrate (SnCl2 2H2O) in alkali solution, while sucrose was used as the carbon source to form the coated polysaccharide shell on the SnO2 nanoparticles. In the obtained carbon-coated SnO2 nanoparticles, SnO2 nanocrystals with a diameter of 4 nm were observed to be homogeneously dispersed in the particles"

Yang, R., Zhao, W., Zheng, J., Zhang, X., Li, X.

Beijing National Laboratory for Molecular Sciences (BNLMS), College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China

Tin Oxide-Based Sputtering Target, Transparent and Conductive Films

Factiva: "Tin Oxide-Based Sputtering Target, Transparent and Conductive Films, Method for Producing Such Films and Composition for Use Therein' was invented by Prabhat Kumar (Framingham, Mass.), Richard Wu (Chelmsford, Mass.) and Shuwei Sun (Framingham, Mass.).

According to the abstract released by the U.S. Patent & Trademark Office: 'The present invention is directed to a composition consisting essentially of: a) from about 60 to about 99 mole % of SnO2, and b) from about 1 to about 40 mole % of one or more materials selected from the group consisting of Nb2O5, NbO, NbO2, WO2, a material selected consisting of a mixture of MoO2 and Mo and Mo, W, Ta2O5, and mixtures thereof,wherein the mole % s are based on the total product and wherein the sum of components and is 100. The invention is also directed to the sintered product of such composition, a sputtering target made from the sintered product and a transparent electroconductive film made from the composition.'"

Dec. 16 -- United States Patent no. 7,850,876, issued on Dec. 14, was assigned to H.C. Starck Inc. (Newton, Mass.)

Researchers experiment with nanowires to improve battery efficiency

The Tech Report: "Although this news broke last week, it's particularly interesting in light of yesterday's discussion of the innovations IBM thinks will emerge in the next five years. A tenfold increase in battery life was on that list, and researchers have made a new discovery that could improve the longevity of lithium ion cells.

Scientists from the Pacific Northwest and Sandia National Laboratories used an transmission electron microscope to look inside a custom-built lithium ion battery. They found that the thin wires of tin oxide that typically make up a battery's electrode twist and deform as electrons flow through them. The wires became longer and fatter as they twisted, increasing in volume by about 250%. In addition to deforming, the internal structure of the wires changed from a crystalline form to a glassy material whose atoms were arranged more randomly."

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New transparent electrodes for highly flexible electronics created

domain-b.com: "Researchers at the UCLA Henry Samueli School of Engineering and Applied Science have now developed a new transparent electrode based on silver nanowires (AgNW) that could replace ITO.

The new electrode uses low-cost, non-toxic and stable materials and is easy to fabricate. It is produced on a cross-linked, transparent polyacylate substrate, which is cheaper than glass and can be stiff and rigid or flexible and stretchable."

Indonesia's Timah stops 6 small tin dredges after green protest

Intellasia.Net: "Indonesia's state-owned PT Timah temporarily stopped operations of six small tin dredges after protests from a local green group, the company's spokesman said on Wednesday.

It was not immediately clear if the action, which started on Wednesday, would affect production for next year, but it could potentially curb supplies from the world's largest integrated tin miner if it runs for a long period of time.

Timah has been boosting off-shore production because of declining, more easily mined onshore reserves on the country's main tin-producing islands off Sumatra."

Top 10 Renewable Energy Technology Breakthroughs In 2010

Ecofriend: "Researchers at IBM created an inexpensive solar cell from materials that are dirt cheap and easily available. The layer that absorbs sunlight and converts it into electricity is made with copper, tin, zinc, sulfur and selenium. The best part of the solar cell is that it still manages to hit an efficiency of 9.6 percent, which is much higher than earlier attempts to make solar panels using similar materials."

Commodities - EIU's quarterly tin outlook

Factiva: "World tin consumption, based on World Bureau of Metal Statistics (WBMS) data, increased by 20% year on year in the first nine months of 2010, driven by a broad-based recovery in demand across all of its main end-use markets. The Economist Intelligence Unit expects that global tin consumption will have continued to increase in the final quarter of 2010, although at a much reduced year-on-year rate owing in part to base effects, resulting in a rise of nearly 15% to over 365,000 tonnes for the year as a whole. In 2011 and 2012 we forecast that the rate of growth in tin consumption will slow to 1.2% and 3.3%, respectively"

Graphene electrodes for organic solar cells

MIT news: "The standard material used so far for these electrodes is indium-tin-oxide, or ITO. But indium is expensive and relatively rare, so the search has been on for a suitable replacement. Now, a team of MIT researchers has come up with a practical way of using a possible substitute made from inexpensive and ubiquitous carbon. The proposed material is graphene, a form of carbon in which the atoms form a flat sheet just one atom thick, arranged in a chicken-wire-like formation.

An analysis of how to use graphene as an electrode for such solar cells was published on Dec. 17 in the journal Nanotechnology, in a paper by MIT professors Jing Kong and Vladimir Bulović along with two of their students and a postdoctoral researcher."

FTO electrodes for electrochemical pharmaceutical reactions

Factiva: "A novel application of fluorine-doped tin oxide (FTO) electrodes is reported in the present work. To this end, the captopril electrochemical oxidation mechanism on FTO electrodes at various pH and its determination in pharmaceutical preparations was investigated"

The researchers concluded: "These electrodes are promising candidates for the efficient electrochemical determination of captopril in pharmaceutical preparations."

Armijo and colleagues published their study in Electroanalysis (Captopril Electrochemical Oxidation on Fluorine-Doped SnO2 Electrodes and Their Determination in Pharmaceutical Preparations. Electroanalysis, 2010;22(19):2269-2276).

For additional information, contact F. Armijo, Pontifical Catholic University, Faculty Quim, Av Vicuna Mackenna 4860, Casilla 306, Correo 22, Santiago, Chile.

Phenols; Reports outline phenols study findings from Xi'an Jiao Tong University

Factiva: "Phenol degradation on novel nickel-antimony doped tin dioxide electrode,' new data in phenols. 'Nickel and antimony doped tin dioxide is a novel anodic material for its good performance of electrochemical ozone generation and direct electro-catalytic oxidation. Electro-catalytic oxidation of phenol on this novel nickel-antimony doped tin dioxide electrode is presented here,' investigators in People's Republic of China"

"The morphology and composition of the electrode are characterized. The effects of applied current densities on phenol degradation rate, energy consumption and coulomb efficiency are discussed. In 0.1 M sulfuric acid, after 4 h electrolysis with current density of 25 mA cm(-1), 90% phenol is removed. And with current density of 20 mA cm(-1), the highest energy efficiency of 6.85 g kWh(-1) and the highest coulomb efficiency of 6.87 g C(-1) are obtained," wrote Q.Y. Chen and colleagues, Xi'an Jiao Tong University.

The researchers concluded: "The effect of current densities on TOC removal is also discussed."

Chen and colleagues published their study in Water Science and Technology (Phenol degradation on novel nickel-antimony doped tin dioxide electrode. Water Science and Technology, 2010;62(9):2090-5).

For additional information, contact Q.Y. Chen, State Key Laboratory of Multiphase Flow, Faculty of Energy and Power Engineering, Xi'an Jiaotong University, Xi'an 710049, China.

Congress toughens definition of "lead free"

AWWA: "The U.S. Congress has approved and sent to the White House for President Obama’s signature a bill toughening the definition of “lead-free” in solder, flux, pipe and fixtures. Endorsed by AWWA’s Water Utility Council, S.3874 was approved by the Senate on Thursday and the House on Friday.

Under the measure sponsored by Sen. Barbara Boxer, D - Calif., lead free' would mean having not more than 0.2 percent lead in solder and flux and not more than a weighted average of 0.25 for wetted surfaces of pipes, fittings, fixtures. This is similar to California’s state standards. There is a formula described in the bill text for these calculations.

'AWWA applauds Congress for passing legislation that further reduces the amount of lead in new plumbing materials,' said Tom Curtis, AWWA Deputy Executive Director for Government Affairs"