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Information × Registration Number 0305U001621, 0104U007377 , R & D reports Title The research and development of the soldering technology of ultrapure corundum ceramics by oxide solders in the system MeO-Al2O3-SiO2 (MeO-CaO, BaO, MnO). Section 4. Research of influence modifying additions on solders properties, development of soldering technology. popup.stage_title Дослідження і розробка технології паяння високочистої корундової кераміки оксидними припоями у системі MeO-Al2O3-SiO2, ( MeO-CaO, BaO, MnO) та випуск дослідних партій. Розділ 4. Дослідження впливу введення модифікуючих додатків на властивості припоїв, розробка технології паяння. Head Kryvoruchko P., Registration Date 24-03-2005 Organization The open joint stock company " The Ukrainian research institute of refractories named A.S.Berezhnoy" popup.description2 Research object - oxide solders of MeO-Al2O3-SiO2 system where MeO-CaO, BaO, MnO with additives of TiO2 and ZrO2 for soldering of ultrapure corundum ceramics. Work purpose - to ascertain an influence of modifying additives on properties of oxide solders, seals on their basis and the technology work - out of soldering of highpure corundum ceramics with oxide solders of MeO-Al2O3-SiO2 system where MeO-CaO, BaO, MnO. Research methods - a microstructure of solders after an introduction of catalysts TiO2 and ZrO2 was researched using a electronmicroscope method. The study of a thermal expansion of oxide solders after an introduction of TiO2 and ZrO2 was determined by means of quartz dilatometer method. The bending strength of seals on the basis of modified solders was determined in accordance with 4 points loading system. An influence of modifying additives on the properties of solders and seals on their basis was researched. A microstructure of solders modified with TiO2 and ZrO2 was studied using electronmicroscopic method. It was ascertained that introduced additives lead to a forming of liquation regions and separations practically in all solders modified with TiO2 and ZrO2. On the basis of a solder N 2 crystallized with modifying aids selfcrystallized composition has been produced after on introduction of 5 weight % of TiO2. Results of DTA showed that in all solders containing modifying aids a crystalline phase is formed and a microstructure of solders crystallized with a structure of glassceramics type without additives of modifying aids was identical to a microstructure of the same solder after an introduction of modifying aid ZrO2. The thermal expansion of modified solders was detrmined by means of experiment. It was ascertained that an introduction of 5 weight % of TiO2 and ZrO2 influences insignificantly on a value of the thermal expansion of solders which were crystalized without modifying aid and increases it by 5% in solders having a lesser inclination towards a crystallization. As a resultof carried out thermal processing in all solders at the expanse of a crystalline phase forming a point of dilatometric softening was increased by 25 C. An influence of introduced modifying aid amount and of holding time at soldering temperature on the bending strength of seals produced with a help of modified solders was studied. It was established that an introduction of 2 and 5 weight % ultimate strength of a seal ( up to 10%) is increased. Maximum increase of a seal (up to 10%) is obtained at an introduction of 5 weight percents of additives into seals which were slightly crystallized without modifying aid. In solders which were formed without additives of TiO2 and ZrO2 fine crystallized structure of glasceramic type a maximum strength was reached at an introduction of 2 weight was equal to 3 - 5 %. It was determined that a holding time increase from 5 up to 30 minutes leads to a growth of a bending strength in all seals. During a holding increase from 30 up to 60 minutes the strength of seals on the basis of solders formed with forming a structure of glassceramics type was decreased. In solders which had a slight inclination to wards a crystallization the valuce of with a holding time increase from 30 up to 60 minutes increased. Carried out research made possible to work - out a soldering technology of ceramic products using solders modified with TiO2 and ZrO2 that ensured a high strength and vacuum density of produced seals.Results of a carried - out work were used when manufacturing a trial lot of soldered ceramic products. In accordance with a given contract a solder of a following composion : CaO - 29,2%; Al2O3 - 39%; SiO2 -31,8% with an additive of 2 weight percents of TiO2 over 100% was used. Besides that a trial lot of metalceramic insulators was produced. Product Description popup.authors popup.nrat_date 2020-04-02 Close