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- 1. Investigation of the wetting behavior of iron base alloys on boron nitride substrates Berg- und Hüttenmännischer Tag 2016, Freiberg Maxim Morshchagin, Dr.-Ing. T. Dubberstein, Prof. Dr.-Ing. O. Volkova Institute of Iron and Steel Technology (IEST), TU Bergakademie Freiberg, Leipziger Straße 34, 09599 Freiberg, Germany *Corresponding author’s Tel: +49 15784747963, E-mail: maxmorshchagin@yandex.ru
- 2. 2 Content | TU Bergakademie Freiberg | Institut für Eisen- und Stahltechnologie | Leipziger Straße 34, 09599 Freiberg | +49 3731 393100 | www.stahltechnologie.de | Vortragender: Maxim Morshchagin | 10.06.2016 | 1. Introduction 2. Motivation 3. Research study 3.1. Research of alloys with nickel 3.2. Research of alloys with chrome 3.3. Research of alloys with manganese 4. Conclusion
- 3. 3 Introduction | TU Bergakademie Freiberg | Institut für Eisen- und Stahltechnologie | Leipziger Straße 34, 09599 Freiberg | +49 3731 393100 | www.stahltechnologie.de | Vortragender: Maxim Morshchagin | 10.06.2016 | To determine the contact angle of binary iron alloys on boron nitride substrates; As an alloy component X nickel, manganese, chrome, are selected; Investigation of the Fe-X/BN interface with the use of X-ray scanning electron microscope; Thermodynamic calculations of Fe-X/boron nitride; Estimation of a possibility of industrial use of boron nitride on the horizontal continuous casting machine.
- 4. 4 Motivation | TU Bergakademie Freiberg | Institut für Eisen- und Stahltechnologie | Leipziger Straße 34, 09599 Freiberg | +49 3731 393100 | www.stahltechnologie.de | Vortragender: Maxim Morshchagin | 10.06.2016 | 𝒄𝒐𝒔 Ɵ = σ 𝑺𝑮 − σ 𝐒𝐋 σ 𝐋𝐆 (1)σ 𝐒𝐆 σ 𝐒𝐋 σ 𝐋𝐆 Full wetting No wetting σSG - surface tension between solid and gaseous phases σLG - surface tension between liquid and gaseous phases σSL - surface tension between solid and liquid phases 𝝉 − adhesive force (Work of adhesion)
- 5. 5 Motivation | TU Bergakademie Freiberg | Institut für Eisen- und Stahltechnologie | Leipziger Straße 34, 09599 Freiberg | +49 3731 393100 | www.stahltechnologie.de | Vortragender: Maxim Morshchagin | 10.06.2016 | 𝐖𝐚 = σ 𝐒𝐆+σ 𝐋𝐆-σ 𝐒𝐋 (2) Work of adhesion 𝑾 𝒌 = 𝟐σ 𝐋𝐆 (3) Work of cohesion
- 6. 6 Motivation Sessile drop method | TU Bergakademie Freiberg | Institut für Eisen- und Stahltechnologie | Leipziger Straße 34, 09599 Freiberg | +49 3731 393100 | www.stahltechnologie.de | Vortragender: Maxim Morshchagin | 10.06.2016 | 1) Test sample placement; 2) gas evacuation; 3) argon-Pressure-Filling; 4) heating of the test samples and recording the data of the oxygen partial pressure in the chamber; 5) сooling and taking photos; 6) pull out to the testing sample of the chamber of the microscope; 7) weighing; 8) data computing.
- 7. 7 Results Research of alloys with nickel 120 125 130 135 140 145 150 1480 1500 1520 1540 1560 1580 1600 1620 WETTINGANGLE,DEG TEMPERATURE, ˚C FeNi3(1) FeNi3(2) FeNi3(3) 136 141 146 151 156 1480 1500 1520 1540 1560 1580 1600 1620 WETTINGANGLE,DEG TEMPERATURE, ˚C FeNi9(1) FeNi9(2) FeNi9(3) 1) Experiments proceeded without strong chemical reaction; 2) in all cases the surface of a substratum looked equally; 3) two experiments of three had good convergence of results. FeNi3(1) FeNi9(3)
- 8. Results The investigation of the ceramics after the experiment with nickel | TU Bergakademie Freiberg | Institut für Eisen- und Stahltechnologie | Leipziger Straße 34, 09599 Freiberg | +49 3731 393100 | www.stahltechnologie.de | Vortragender: Maxim Morshchagin | 10.06.2016 | C (investment material) Zr O Si 8 Cristobalite SiO2 FeNi9
- 9. 9 Results Research of alloys with Chrom 110 120 130 140 150 160 1480 1500 1520 1540 1560 1580 1600 1620 WETTINGANGLE,DEG TEMPERATURE, ˚C FeCr3(1) FeCr3(2) 100 110 120 130 140 150 1480 1500 1520 1540 1560 1580 1600 1620 WETTINGANGLE,DEG TEMPERATURE, ˚C FeCr16(1) FeCr16(2) 1) Oscillating motion of a drop on a substrate was observed; 2) cavities in a drop body were found; 3) there is no connection between concentration of the alloying element and cavities in a drop. FeCr3(1) FeCr3(2) FeCr16(1) FeCr16(2)
- 10. Results The investigation of the ceramics after the experiment with Chrom | TU Bergakademie Freiberg | Institut für Eisen- und Stahltechnologie | Leipziger Straße 34, 09599 Freiberg | +49 3731 393100 | www.stahltechnologie.de | Vortragender: Maxim Morshchagin | 10.06.2016 | C (investment material) Zr Cr B Fe 10 FeCr16 Cr2B
- 11. 11 Results Research of alloys with manganese 110 115 120 125 130 135 140 1480 1500 1520 1540 1560 1580 1600 1620 WETTINGANGLE,DEG TEMPERATURE, ˚C FeMn3(1) FeMn3(2) 90 100 110 120 130 140 1480 1500 1520 1540 1560 1580 1600 1620 WETTINGANGLE,DEG TEMPERATURE, ˚C FeMn15(1) FeMn15(2) 1) Oscillating motion of a drop on a substrate was observed; 2) the drop could move on a substratum surface; 3) intensive gas discharge from under a liquid phase.FeMn3(1) FeMn3(2) FeMn15(1) FeMn15(2)
- 12. Results The investigation of the ceramics after the experiment with Mangan | TU Bergakademie Freiberg | Institut für Eisen- und Stahltechnologie | Leipziger Straße 34, 09599 Freiberg | +49 3731 393100 | www.stahltechnologie.de | Vortragender: Maxim Morshchagin | 10.06.2016 | C (investment material) Zn Si Mn O 12 FeMn15 Rhodonit MnSiO3
- 13. 13 Conclusion With the advent of a gas bubble in a drop body the measured wetting angle strongly changes. The bubble of gas makes a drop visually higher, and the wetting angle decreases. FeCr3(1) FeCr3(2)
- 14. Conclusion 100 110 120 130 140 150 160 0 2 4 6 8 10 12 14 16 18 WETTINGANGLE,DEG ALLOY CONTENT, % FeNi1600 FeMn1600 FeCr1600 FeNi1500 FeMn1500 FeCr1500 Such elements as chrome and manganese improve wettability. Nickel in an alloy worsens wettability (increases the wetting angle). 14
- 15. 15| TU Bergakademie Freiberg | Institut für Eisen- und Stahltechnologie | Leipziger Straße 34, 09599 Freiberg | +49 3731 393100 | www.stahltechnologie.de | Vortragender: Maxim Morshchagin | 10.06.2016 | Thank you for your attention! Maxim Morshchagin
Editor's Notes
- Good morning ladies and gentlemens. My name is Maxim Morshchagin and I'm a student of TU Bergakademie Freiberg, Institute of Iron and Steel Technology. As you already know, today’s presentation is designed to present some important points of Investigation of the wetting behavior of iron base alloys on boron nitride substrates.
- This first slide shows our agenda for the presentation. First, I will begin with the short introduction. Then I would like you to have a look at the overview of the wetting phenomena. Then I would like to pay attention to the experiments I’ve made and to results. At last I would like to state several assumptions about results of experiences and the main recommendations.
- What faced work performance? Why we made this research? That work was carried out to determine the contact angle of binary iron alloys on boron nitride substrates. Moreover, research was made on purpose to estimate a possibility of industrial use of boron nitride on the horizontal continuous casting machine.
- In the scientific research, a special term "contact angle" is used to graphically characterize the wettability of the liquid on a substrate. It is possible to determine the degree of liquid wetting of the solid substrate by measuring the contact angle. For measuring a contact angle the method of sessile drop was applied. On this slide the formula for determination of wetting angle is shown. Also on this slide you can find possible types of wetting.
- The wetting phenomena is the ability of a liquid to maintain the contact with a solid surface, resulting from intermolecular or interfacial interactions, when the two phases (liquid and solid) are contacted. The equilibrium force balanced between the adhesive and the cohesive forces determines the degree of wetting (wettability).
- Within the present investigation, some experiments were performed to determine the contact angle of binary iron alloys on boron nitride substrates. The research was made with the sessile drop method using a hot stage microscope and argon atmosphere (99.999 vol%, < 2 ppm O2). Pieces of alloys in cubic form, weighting 5 g each, were melted on a boron nitride substrate (ca. 40 % ZnO, ca. 40 % BN, ca. 16 % SiO2) with a 30 mm diameter. Several alloying elements like chromium, manganese and nickel have an influence on the work of cohesion. The interfacial reaction between the substrate and the liquid phase, the oxygen content in the furnace atmosphere and the experimental time within the present experiments were analyzed according the contact angle.
- The series of experiments with nickel should be pointed out, that a strong interaction between nickel and boron nitride substrate were not observed. Therefore, we can supervise the dependence of the contact angle alternation concerning the temperature and the time of wetting only. Any craters on the site of the melted place was not detected. Because the drop was not oscillating on the substrate, a high reproducibility was seen.
- The contact angle as a function of temperature in the scanning electron microscope were analyzed. The thermodynamic calculations presented, that during the reaction between the substrate and the melt material, nitrogen was released and new phases were formed. A new phase of Cristobalite. Gluing of a drop to a substrate does not occur, and even a small amount of nitrogen gas, released during the melting, easily get into the chamber.
- Research studies on the influence of the presence of chromium on the wetting of boron nitride ceramics, by binary alloys based on iron, have shown that with an increase of the chromium concentration in iron alloys the investigated contact angle decreased.
- During the experiments it was found that a strong chemical reaction occurs between substrate and melt. According to the calculations in the Thermo-Calc software, Cr2B or Fe2B phase appears, drop glue to the substrate, and nitrogen is collected in the drops body.
- Research of alloys with manganese. The diagram shows the time, until the drop remained unstable and active reaction took place. At the beginning of the measurement, when the melt reacts with the ceramic substrate, the variation in the results of the angle measurement is great. At a temperature of 1560 °C, the drop is stable. Until the end of the measurements, when the temperature is 1500 °C, the contact angle decreases. This hints that the work of adhesion increases.
- When alloys with manganese heated to a temperature of 1500 °C and melted, a strong reaction with the formation of the Rhodonite (chemical formula - (Mn2+)SiO3) is observed in the article (regardless of the manganese concentration). The formation of manganese nitrides is also possible. Within the reaction a crater could be formed.
- It is assumed that the gas bubble in the drops body can greatly affect the value of the wetting angle and the convergence of the results of the research study. Bubble makes the drop higher, what reduces the wetting angle, which is measured by a drop photo.
- If to pass to conclusions, then the following items should be noted. During the present research project, the influence of the contact angle of various iron binaries on BN substrates was determined. Nickel in an alloy worsens wettability (increases the wetting angle). It is certainly possible to define influence of manganese and chrome on wetting. The wetting angle decreases, wetting improves, work of adhesion increases.