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Information × Registration Number 0306U001194, 0105U003072 , R & D reports Title Research of formation, destruction and recovery processes of coagulatory structures in vibrocast grainy thixotropic masses from calcia stabilized by zirconia and trial lots production of crucibles for the induction melting of platinum and it's alloys. popup.stage_title Дослідження процесів утворення, руйнування та відновлення коагуляційних структур у вібролітих зернистих тиксотропних масах із діоксиду цирконію, стабілізованого CaO та випуск дослідних партій тиглів для плавки платини та її сплавів. Head Shulik I., Registration Date 09-02-2006 Organization The open joint stock company " The Ukrainian research institute of refractories named A.S.Berezhnoy" popup.description2 The subject of investigation - vibrocast products from stabilized ZrO2, for metal fusion of platinum group. The purpose of the work - the production technology specification of ZrO2 products, stabilized by CaO by means of vibrocasting. Methods of research - chemical, roentgenophase, determination methods of physico-mechanical properties factors of refractory products, determination procedure of flowability under vibration of boundary- concentrated thixotropic grain masses, determination procedure of structure plastic strength using conic plastometer of P.A. Rebinder. The processes of structures formation and disintegration in vibrocast grain thixotropic masses from zirconia, stabilized by СаО, were investigated in the work, while introduction ГКЖ-11 Н and ГКЖ-11 К additions, as well as the influence of ГКЖ-11 K addition in comparison with ГКЖ-11 Н addition on flowability under vibration of specified masses was investigated. In connection with, that during the work had been established, that even longaffection of vibration (up to 70 mines) practically did not lead to disintegration of the formed structures in vibrocast masses at introduction of ГКЖ-11 Н addition, but at introduction of ГКЖ-11 K addition, formation of structures in the given masses was insignificant, processes of structures reduction, disintegrated under vibration, were not investigated in the given work. The mechanism of formation and disintegration processes of coagulatory structures in vibrocast grain thixotropic masses from zirconia, stabilized by СаО, was investigated. The influence on formation process kinetics of coagulatory structures in the investigated masses of concentration (humidity) of system, as well as amount and type of ПАВ was established. It was established, that formation process of coagulatory structures at introduction of ГКЖ-11 Н addition was carried out stepwise in two stages with formation of aggregates at the first stage of process and formation of wireframe structure from them at the second one. The first stage of formation process of coagulatory structure runs 4 times quicklier, than the second one and during this time, plastic strength of masses reaches half of all strength of formed structure. At introduction of ГКЖ-11 K addition formation of coagulatory structure occurs considerably less intensively. It was established for the first time, that formed at the introduction ГКЖ-11 Н eventually coagulatory structure in the investigated masses practically does not disintegrate when affecting by vibration, up to 70 minutes of its application. It is established, that from a series of water-repellent organosilicon ГКЖ-11 fluids, the most efficient is the use of ГКЖ-11 Н, introduction of which in amount of 0,15 % provides maximal flowability of the mass under vibration. On the pilot production of the institute, crucibles from zirconia, stabilized by СаО, zirconia, stabilized by Y2О3 were manufactured. Crucibles from ZrО2, stabilized by СаО, were characterized by the following properties - mass proportion, %: ZrO2+НfO2-93,9-95,4; СаО- 3,9-5,0; Fе2О3-0,11-0,31; open porosity - 15,2-21,7%; apparent density 4,41-4,55 g/sm3. Crucibles from ZгО2, stabilized by Y2Оз, were characterized by the following properties: mass proportion, %: ZrO2+НfO2- 89,1-90,1; Y2О3- 9,3-10,0; Fе2О3-0,15-0,18; ; open porosity - 15,3-18,2 %; apparent density - 4,87-5,g/sm. According to their properties, the manufactured crucibles correspond to customers demands. The manufactured products were put to customers. To continue the work towards influence investigation of vibration parameters (amplitude and frequency) on properties of masses for vibratocasting and green products from stabilized zirconia, as well as towards detailed influence research of monoclinic zirconia addition in amount of 20-40 % on properties of products from zirconia stabilized by СаО. Product Description popup.authors popup.nrat_date 2020-04-02 Close