Optimization of technology for production of condenser agglomerated tantalum powder

G.A. Kokayeva; А.V. Revutskiy; S.A. Abdulina; M.A. Adіlkanova

doi:10.31643/2018/6445.38

Authors

G.A. Kokayeva S.Seifullin Kazakh agrotechnical university
А.V. Revutskiy Ulba Metallurgical Plant
S.A. Abdulina D.Serikbayev East Kazakhstan state technical university
M.A. Adіlkanova D.Serikbayev East Kazakhstan state technical university

DOI:

https://doi.org/10.31643/2018/6445.38

Keywords:

condenser, tantalum powder, agglomeration, dehydrogenation, sintering, ramming, powder flow rate.

Abstract

The urgency of the problem specifies the development of modern technology, in particular the production of capacitors, which is impossible without the creation of new materials to improve the parameters of products. The work aim is solving an applied technical problem – the creation of capacitors with improved electrical characteristics. The technological scheme of production of modified condenser powders, the chemical composition and electrical characteristics of the capacitor tantalum powder are investigated. The effect of sintering temperatures (1500-1600 °C) on the physical and electrical characteristics of the capacitor tantalum powder is studied. Main characteristics of the powder are charge, bulk density, particles size according to Fisher, strength of unsintered anode. To obtain products that meet modern requirements, the existing technology for the production of agglomerated powder (AGP) is improved by introducing additional operations, such as compacting the material before loading into the furnace, as well as re-sintering. Several variants of preparation of the primary condenser tantalum powder for thermal treatment at temperatures 1500-1600 °C are studied. The favorable effect of preliminary chemical treatment with solutions of hydrochloric and hydrofluoric acids with the addition of hydrogen peroxide of the initial tantalum powders on the increase of the specific charge of the finished AGP was established. To obtain AGP with the optimum properties, it is necessary to use tantalum containers with lids for the dehydration of the primary condenser powder. Obtained with the free filling of the hydride into the box agglomerate of the AGP has a lower bulk density and an average grain size according to Fisher, as well as a greater strength of the unsintered anodes compared to the powder obtained by compaction. Nevertheless, the AGP obtained by compacting the hydride before agglomeration allows obtaining AGP with characteristics meeting all modern requirements. This characteristics are charge in the range of 4000-4500 μC/g, the leakage current is not more than 0.23 nA/μC, the bulk density in the range 3.5-4.0 g/cm3, Fischer particle size in the range of 8-1 micrometer, strength of the unsintered anode more than 30 Н, magnesium content less than 3 ppm.

Downloads

Download data is not yet available.

Author Biographies

G.A. Kokayeva, S.Seifullin Kazakh agrotechnical university

Candidate of Technical Sciencescting assistant professor, Technical Faculty, Department “Technological machines and equipment”, S.Seifullin Kazakh Agro Technical University, Аstаnа, Kazakhstan.

А.V. Revutskiy, Ulba Metallurgical Plant

Production supervisor at production of condenser powders, Ulba Metallurgical Plant, Ust-Kamenogorsk, Kazakhstan.

S.A. Abdulina, D.Serikbayev East Kazakhstan state technical university

Doctor PhD, Assisstant professor (docent), The Faculty of Earth Sciences, Department “Metallurgy of Non-Ferrous and Rare Metals”, D.Serikbayev East Kazakhstan state technical university, Ust-Kamenogorsk, Kazakhstan.

M.A. Adіlkanova, D.Serikbayev East Kazakhstan state technical university

Doctor PhD. Head of sub-department, The Faculty of Earth Sciences, Department “Chemistry and concentration of mineral resources, D.Serikbayev East Kazakhstan state technical university, Ust-Kamenogorsk, Kazakhstan.

References

Orlov V.M. Issledovaniye i razrabotka materialov na osnove tantala i niobiya dlya elektronnoj tekhniki (Research and development of materials based on tantalum and niobium for electronic technology): avtoref. dis. ... dokt. tekhn. nauk (Abstract of a thesis for Doctor of Tech. Sci.): 05.16.03 / Sankt-Petersburg state mining institute of G.V. Plekhanov. Sankt-Petersburg, 2000. 47. (in Russ.)

Markushkin Yu.E., Azarov V.D., Nebera A.L. Tantalovyye poroshki dlya ehlektroliticheskikh kondensatorov (Tantalum powders for electrolytic capacitors). Tsvetnye metally = Nonferrous metals. 2005. 7, 89-90. (in Russ.)

Anderson K. Die Bedentung des Tantals in der Kondensatorindustrie. Erzmetal. 1995. 48, 430-434. (in Germ.)

Starostin S.P. Fiziko-khimicheskiye osnovy tekhnologii proizvodstva tantalovykh anodov i katodov kondensatorov iz aglomerirovannykh nanokristallicheskikh poroshkov(Physicochemical foundations of the technology for the production of tantalum anodes and cathodes of capacitors made from sintered nanocrystalline powders). Diss. ... kand. tekh. nauk (Thesis for cand. of Tech. Sci.): 05.16.06 / Institute of metallurgy UrB of RAS. Ekaterinburg, 2016. 94. (in Russ.)

Jones A. The tantalum and niobium markets: trends in supply, demand and applications. Internation. Symp.on Tantalum and Niobium:proceedings of the symp. Orlando, USA. 1988. 19-41. (in Eng.)

Nebera A.L., Lizunov A.V., Semenov A.A. Tantalovyye poroshki s nanokristallicheskoy strukturoy: polucheniye. svoystva. perspektivy ispolzovaniya(Tantalum powders with a nanocrystalline structure: production, properties, prospects of use). Kompozity i nanostruktury=Composites and nanostructures.2015. 3, 121-126. (in Russ.)

Pat. 2242329 RU. Sposob polucheniya poroshka tantala (The method for producing tantalum powder). / Markushkin Yu.E., Azarov V.D., Ermolayev N.M., Nebera A.L. publ. 20.12.2004. Bul. 35. 7. (in Russ.).

Orlov V.M., Kolosov V.N., Prokhorova T.Yu., Miroshnichenko M.N. Issledovaniya po tekhnologii vysokoyemkikh tantalovykh kondensatornykh poroshkov (Research on the technology of high-capacity tantalum capacitor grade powders). Tsvetnye metally=Non-ferrous metals. 2011. 11, 30-35. (in Russ.)

Kim Y., Lee D., Hwang J., Ryu HJ., Hong SH. Fabrication and characterization of powder metallurgy tantalum components prepared by high compaction pressure technique. Materials characterization. 2016, 114, 225-233. https://doi.org/10.1016/j.matchar.2016.03.005

Kim Y., Kim E.P., Noh J.W., Lee S.H., Kwon Y.S., Oh I.S. Fabrication and mechanical properties of powder metallurgy tantalum prepared by hot isostatic pressing. International journal of refractory metals & hard materials. 2015. 48, 211-216. https://doi.org/10.1016/j.ijrmhm.2014.09.012

Efe M., Kim H.J., Chandrasekar S., Trumble K.P. The chemical state and control of oxygen in powder metallurgy tantalum. Materials science and engineering a-structural materials properties microstructure and processing. 2012. 544, 1-9. https://doi.org/10.1016/j.msea.2012.01.100

Treshchev S.Yu., Starostin S.P., Mikhaylova S.S., Kanunnikova O.M., Pushkarev B.E., Gilmutdinov F.Z., Sobennikova M.V., Ladianov V.I., Lebedev V.P. Sravnitel’nyj analiz sostava i struktury kondensatornykh poroshkov tantala (Comparative analysis of the composition and structure of condenser tantalum powder). Khimicheskaya fizika i mezoskopiya=Chemical physics and mesoscopy. 2014. 16, 609-615. (in Russ.)

Zelikman A.N., Korshunov B.G.Metallurgiya redkikh metallov (Metallurgy of Rare Metals). Moscow: Metallurgy. 1991. 430. (in Russ.)

Songina O.A. Redkiye Metally (Rare Metals). Moscow: Literature on ferrous & non-ferrous metallurgy. 1955. 384. (in Russ.)

Pat. 2210463 RU. Sposob polucheniya poroshka metallicheskogo tantala s kontroliruyemym raspredeleniyem razmerov i produkty, poluchayemyye iz nego (Method for obtaining dust of metal tantalum by controlled size distribution and products from it) / Patkhar V.M.. Rao Bkhamidipati K.D., Fayf D.A.; publ. 20.08.2003. Bul. 23. 16. (in Russ.)