Mission: To investigate gases in glass and gas inclusions and determine their influence on glass quality and properties
TC14 promotes activities to better understand evolution mechanisms of gases in glass and bubble formations. It supports cooperation with other Technical Committees in order to fulfill its mission. Most of its recent activities have been carried out jointly with TC11 and TC18 regarding the influences of glass contact materials and melting process on bubble formation. TC14 always welcomes to other technical groups and/or individual participants for cooperative works to promote the basic science in related topics.
- We proudly inform that The Turner Award was given jointly to Dr. Detlef Köepsel (TC14) and Dr. Volker Rupertus (TC19) in the opening ceremony of 2015 Annual Conference in Bangkok. Dr. Köepsel from Schott Glass has completed his term of 9 years as Chairman of TC14, giving his maximum energy and time to TC14 Works.
- Dr. Mustafa Oran from Sisecam was elected as the new chair of TC14.
Activities and Plans
The agenda of TC 14 has already a list of tasks including previous works and the new proposals but TC 14 not been able to hold large-scale meetings in recent years, except review meetings with a very few friends. Therefore, As we’re going to the year 2020, there is a list of possible scientific events where we can organize our TC 14 meeting as well. We would like to organize a meeting conjunction with an international event of 2020, listed below at which we can make a wide discussion of our agenda including past, ongoing and future works.
· USTV-DGG JOINT MEETING (The annual meeting of French Union for Science and Glass Technology (USTV) in conjunction with the 94th Annual Meeting of the German Society of Glass Technology) June 15-19, 2020; Orléans, France.
· The 13th International Symposium on Crystallization in Glasses and Liquids, 16 – 18 September 2020 Paris, France
· 15th ESG CONFERENCE & ICG Annual Meeting 2020; 20-24 September 2020, Kraków, Poland
TC 14 usually organizes its meetings once a year, mostly gathering during the scientific events, such as conferences, workshops, etc. But unfortunately we could have meetings in Istanbul 2017 and in Saint Malo 2018 with very few participants. Therefore, we’ve rather just recalled previous studies but we were not able to discuss/evaluate ongoing projects and the new proposal in detail.
Therefore we consider that some previous topics can be still extended and/or repeated with the new approaches/methods. For example, interrupted dynamic bubble-refractory test or determination of rate of change of bubble size during fining/refining. The followings are subject to evaluate as the new topics to be studied and more activities are always welcome:
- Bubble analysis with other methods than MS (Raman Spectroscopy, know-how restrictions but maybe only on its basic physics)
- Numerical Model of Bubble Behavior (to find a numerical relation between rate of change of bubble size with respect to temperature and glass composition.)
- Bubble formation at sand grains or other relicts (microscopic studies)
On the other hand, a poster and a video record (https://sisecam.sharefile.com/d-553c9a96d76b43f8) for TC 14 have been prepared for ICG2019 in Boston.
The annual meeting of TC14 was proposed by its chair to be held in ICG2017, Istanbul but only 3 participants have informally discussed the possible activities both focused in TC14 alone and connected with other TCs (particularly TC18 and TC11). In this context, investigations on melting kinetics including batch to melt conversion and bubble nucleation based on glass composition, raw materials, time-temperature regime, as well as bubble refractory material interactions would be the subjects given priority.
The chair has suggested to organize the next TC14 meeting at “14th European Society of Glass conference in combination with The 15th International Conference on the Physics of Non-Crystalline”, 09 – 13 July 2018 in Saint Malo, France. But this will be fixed after collecting alternatives if any.
The first activity in 2016 was to prepare a poster presentation of TC14 for displaying in 24th ICG Congress in Shanghai.
The annual meeting of TC14 was held on 5th of September, 2016 at SGT Centenary Conference & ESG2016 in Sheffield, UK.
The first part was a joint meeting of TC14 and TC18 to discuss ongoing topic, “Bubble Nucleation Temperature”. The average results of all RRT participants including preliminary ones are given in Table 1.As shown in Table 1, all laboratories are consistent with their own results so that it might be concluded that Tn of Sisecam seems higher than Tn of AGC. Beside Tn values, bubble diameter change on a Pt wire at elevated temperature for both glasses and results of bubble gas analysis for AGC samples were given by NEG. Sulphur content of AGC and Sisecam glasses were compared with redox state measurement done by UCT Prague and XRF analysis done by Sisecam.
The rest of TC14 agenda was discussed sperately by its participants. As proposed a joint work of TC14 – TC11, the procedures of both static and dynamic Round Robin Tests on refratory bubbles have been defined earlier, but the previous results were not satisfied. These RRT are interrupted since the refractory crucibles for the new tests are not available. This joint work will be rediscussed based on the decision of TC11.
The other topic in the current agenda was to prepare a web page of TC14. After the suggestion of Prof. John Parker, The recent info page of TC14 activities was created into the ICG structure. This form will be evaluated in the next metting to improve the content and accesibility. For the time being, a meeting report will be distrbuted soon to the participants by email.
Regarding the activity plan, TC14 chair will collect the new ideas and/or proposals from the participants and prepare an agenda to be discussed at the next meeting. Dr. Oran has suggested the occasion of ICG Annual Meeting 2017 which will be held in Istanbul, 22th – 25th October 2017, but it was not fixed since a few number of participants were present in the meeting. The location and date of the next meeting is still open for alternative occasions and it will be decided after recieving participants’ ideas.
The first annual meeting of TC14 chaired by Mustafa Oran was held on October 14, 2015 after Glass Trend seminar in Eindhoven. Besides the annual meeting of TC14, a joint meeting of TC11-TC14 was held on the same day. Therefore, the agenda of TC14 meeting has been divided into two sections. The following topics were discussed at TC11-TC14 joint meeting:
. Dynamic Blister Test (discussion on guideline)
. Static Blister Test (RRT-TC11/TC14)
Both activities have been designed as RRT in the past but could not be completed since the experiments of some participants have been failed with the experiments. The guidelines for both dynamic and static blister tests, prepared and revised by Dr. Michael Dunkl, the chair of TC11 were distributed to the participants. The following topics were discussed at TC14 meeting together with TC18 participants:
Nucleation of Bubbles in Glass Melt: This is a RRT work organized together with TC18. Mechanism of bubble nucleation is one of the important subjects to better understand melting and fining processes. The aim of the project is to understand the mechanism and kinetics of bubble nucleation, to restrict bubble defects and to study the effect of bubble nucleation process on melting improvement. First step of the project involves the Round Robin Test on the determination of the nucleation temperature. The proposed method is based on high temperature observation of bubble nucleation on Pt wire immersed in the glass melt. Two samples of commercial float glasses delivered by AGC and Sisecam were chosen for the study. The glass samples have been delivered to the participants: M. Rongen (Celsian), D. Koepsel (Schott), T. Maehara (AGC), M. Kawaguchi (NEG), J. Klouzek (UCT Prague).
Schott and NEG informed that they will complete RRT. On the other hand, common laboratory work of two participants, UCT Prague and Asahi has been published as the paper entitled: Vernerova M., Cincibusova P., Klouzek J., Maehara T., Nemec L.: Method of examination of bubble nucleation in glass melts, Journal of Non-Crystalline Solids 411 (2015) 59–67.
The test procedure based on high temperature observation of bubble nucleation temperature is described in the following Figure 1 and Table 1.
The preliminary results of two glasses given by UCT, AGC and Celsian are shown in Table 2. The results shows that bubble nucleation temperature of AGC glass is lower than Sisecam glass.
The summary of other subjects discussed during the meeting is given below:
CO2 Solubility – comparison of the methods (advantages & disadvantages): Two analytical methods for the determination of CO2 in molten glass; vacuum high temperature extraction and Helium carrier gas extraction give different results for the same samples since both methods have advantages and disadvantages. This was reviewed again and it has been considered that a dedicated meeting with other experts, especially Geochemists would be valuable to discuss the methods. In this context, it was decided to contact primarily with Prof. Dr. Harald Behrens from Institut für Mineralogie Leibniz Universität Hannover.
RRT on Batch Melting: This is another co-activity proposed by TC18 and TC14. TC18 has proposed to develop a standard test to evaluate melting kinetics of glass forming raw materials. TC14 participates to analyze the bubbles nucleated on dissolving sand grains. Jaroslav Klouzek, chair of TC18 was not able to attend the meeting. Instead of him, Mathieu Hubert from Celsian informed TC14 members about Klouzek’s work.
Web Page of TC14: Jan Hermans as a volunteer member will develop a web page of TC14 under official web site of ICG. It was decided that Mustafa Oran will contact with Dr. John Parker for this issue.
Besides ongoing activities of TC14, Mustafa Oran suggested two proposals, considering the need of new topics to be studies. One is to analyze the bubbles by Raman Spectroscopy, a non-destructive method, different from Mass Spectroscopy. Schott and Asahi already have some works on this method. Sisecam has recently started to study this method with a university. This method may not be very accurate and quantitative but it is worthy to investigate. The other one is to find a numerical relation between rate of change of bubble size with respect to temperature and glass composition. Such a definition may be supposed to be used in numerical models. These two proposal are postponed to the near future since ongoing activities have to be completed primarily.
Ceola, Stefano Committee Position: Chair
di Pierro, Simon Pietro
Nemec, Lubomir (Prof)
Committee Contact Details
TC14: Gases in Glass