Liquid silicate additive for alkaline texturing of mono-Si wafers to improve process bath lifetime and reduce IPA consumption

AbstractThe effect of the addition of 2CaO·SiO2 solid particles on dephosphorization behavior in carbon-saturated hot metal was investigated. The research results showed that the addition of 2CaO·SiO2 particles have little influence on desilication and demanganization, and the removal of [Si] and [Mn] occurred in the first 5 min with different conditions where the contents of 2CaO·SiO2 particles addition for the conditions 1, 2, 3, 4, and 5 are 0, 2.2, 6.4, 8.6, and 13.0 g, respectively. The final dephosphorization ratios for the conditions 1, 2, 3, 4, and 5 are 61.2%, 66.9%, 79.6%, 63.0%, and 78.1%, respectively. The dephosphorization ratio decreases with the increase of 2CaO·SiO2 particles in the first 3 min. The reason for this is that the dephosphorization process between hot metal and slag containing C2S phase consisted of two stages: Stage 1, [P] transfers from hot metal to liquid slag and Stage 2, the dephosphorization production (3CaO·P2O5) in liquid slag reacts with 2CaO·SiO2 to form C2S–C3P solid solution. The increase of 2CaO·SiO2 particles increases the viscosity of slag and weakens the dephosphorization ability of the stage 1. The SEM and XRD analyses show that the phase of dephosphorization slag with the addition of different 2CaO·SiO2 particles is composed of white RO phase, complex liquid silicate phase, and black solid phase (C2S or C2S–C3P). Because the contents of C2S–C3P and 2CaO·SiO2 in slag and the dephosphorization ability of the two stages are different, the dephosphorization ability with different conditions is different.

Download Full-text

Use of a Structural Model to Calculate the Viscosity of Liquid Silicate Systems

ISIJ International ◽

10.2355/isijinternational.isijint-2017-483 ◽

2018 ◽

Vol 58 (2) ◽

pp. 220-226 ◽

Cited By ~ 3

Author(s):

Josué López-Rodríguez ◽

Antonio Romero-Serrano ◽

Aurelio Hernández-Ramírez ◽

Miguel Pérez-Labra ◽

Alejandro Cruz-Ramírez ◽

...

Keyword(s):

Structural Model ◽

Liquid Silicate

Download Full-text

A study on transformation of some transition metal oxides in molten steelmaking slag to magnetically susceptible compounds

Journal of Mining and Metallurgy Section B Metallurgy ◽

10.2298/jmmb120811008s ◽

2013 ◽

Vol 49 (2) ◽

pp. 169-174 ◽

Cited By ~ 3

Author(s):

V. Shatokha ◽

A. Semykina ◽

J. Nakano ◽

S. Sridhar ◽

S. Seetharaman

Keyword(s):

Physical Properties ◽

Transition Metal Oxides ◽

Value Added ◽

Steelmaking Slag ◽

Research Directions ◽

Liquid Silicate ◽

Metallurgical Slags ◽

Institute Of Technology ◽

National Metallurgical Academy ◽

Kinetics Of

Sustainable development of steelmaking requires solving a number of environmental problems. Economically feasible and environmentally friendly recycling of slag wastes is of special concern. Research of the team representing National Metallurgical Academy of Ukraine, Royal Institute of Technology, Carnegie Mellon University and URS Corp revealed a possibility of the controlled phase transformations in the liquid silicate melts followed by formation of the magnetically susceptible compounds. This approach enables selective recovery of metal values from slag. In this paper, the results obtained and further research directions are discussed. A possibility to exploit physical properties of the transition metals, typical for the metallurgical slags (such as Fe, Mn, V and others), and corresponding specific properties of their compounds, such as non-stoichiometry, mixed valency, pseudomorphosis, thermodynamic stability etc, in production of value-added materials from slag wastes is discussed. The results of the studies of thermodynamics and kinetics of oxidation in slags followed by phase transformation with binary, ternary and complex oxides under various physicochemical conditions are discussed in the view of their application for production of the materials with predefined physical properties. Peculiarities of precipitation in slags with various basicities are analysed and demonstrate capacity of the proposed approach in the production of the material with a given structure and size - for example, nano-sized crystals with structure of spinel. The approaches towards industrial realization of the developed method are also discussed.

Download Full-text

Errata to “The Solubility of Water in Liquid Silicate” [Trans. ISIJ, 6 (1966), No. 5, pp. 225–232]

Transactions of the Iron and Steel Institute of Japan ◽

10.2355/isijinternational1966.7.113_1 ◽

1967 ◽

Vol 7 (2) ◽

pp. 113_1-113_1

Author(s):

Tsutomu Fukushima ◽

Yasutaka Iguchi ◽

Shiro Ban-ya ◽

Tasuku Fuwa

Keyword(s):

Liquid Silicate

Download Full-text

Thermodynamic model calculations in multicomponent liquid silicate systems

Ironmaking & Steelmaking ◽

10.1179/030192301678118 ◽

2001 ◽

Vol 28 (3) ◽

pp. 250-257 ◽

Cited By ~ 19

Author(s):

J. Björkvall ◽

D. Sichen ◽

S. Seetharaman

Keyword(s):

Thermodynamic Model ◽

Model Calculations ◽

Liquid Silicate

Download Full-text

Viscosity model for fully liquid silicate melt

Journal of Mining and Metallurgy Section B Metallurgy ◽

10.2298/jmmb110922011z ◽

2012 ◽

Vol 48 (1) ◽

pp. 1-10 ◽

Cited By ~ 17

Author(s):

Guo-Hua Zhang ◽

Kuo-Chih Chou

Keyword(s):

Activation Energy ◽

Bond Strength ◽

Size Effect ◽

Interaction Force ◽

Silicate Melt ◽

Viscosity Model ◽

Nonlinear Variation ◽

Liquid Silicate ◽

Lower Viscosity ◽

Two Factors

A model for estimating the viscosity of silicate melt as derived in our previous paper is extended to the system containing MgO, CaO, SrO, BaO, Li2O, Na2O, K2O, which can express the nonlinear variation of activation energy of viscosity with the composition. It is found that the optimized parameters of model which characterize the deforming ability of bonds around non-bridging oxygen decrease with increasing the bond strength of M-O bond expressed by I=2Q/RMz+ + rO2-)2 (where Q is the valence of cation M; r is the radius). It is pointed out that viscosity is not only determined by the bond strength, but also by the radius of cation which is defined as the size effect. The radius of cation plays paradox roles in the two factors: smaller radius leads to a stronger bond, thus a higher viscosity; while cations with smaller radius are easier to diffuse when neglecting the interaction force, thus a lower viscosity will be.

Download Full-text

Fate of MgSiO3 melts at core–mantle boundary conditions

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1512386112 ◽

2015 ◽

Vol 112 (46) ◽

pp. 14186-14190 ◽

Cited By ~ 42

Author(s):

Sylvain Petitgirard ◽

Wim J. Malfait ◽

Ryosuke Sinmyo ◽

Ilya Kupenko ◽

Louis Hennet ◽

...

Keyword(s):

Amorphous Materials ◽

High Pressures ◽

Ab Initio Molecular Dynamics ◽

Density Contrast ◽

Mantle Boundary ◽

Core Mantle Boundary ◽

Liquid Silicate ◽

Diamond Anvil ◽

Pressure Regime ◽

Dynamics Simulations

One key for understanding the stratification in the deep mantle lies in the determination of the density and structure of matter at high pressures, as well as the density contrast between solid and liquid silicate phases. Indeed, the density contrast is the main control on the entrainment or settlement of matter and is of fundamental importance for understanding the past and present dynamic behavior of the deepest part of the Earth’s mantle. Here, we adapted the X-ray absorption method to the small dimensions of the diamond anvil cell, enabling density measurements of amorphous materials to unprecedented conditions of pressure. Our density data for MgSiO3 glass up to 127 GPa are considerably higher than those previously derived from Brillouin spectroscopy but validate recent ab initio molecular dynamics simulations. A fourth-order Birch–Murnaghan equation of state reproduces our experimental data over the entire pressure regime of the mantle. At the core–mantle boundary (CMB) pressure, the density of MgSiO3 glass is 5.48 ± 0.18 g/cm3, which is only 1.6% lower than that of MgSiO3 bridgmanite at 5.57 g/cm3, i.e., they are the same within the uncertainty. Taking into account the partitioning of iron into the melt, we conclude that melts are denser than the surrounding solid phases in the lowermost mantle and that melts will be trapped above the CMB.

Download Full-text