Materials for the production of primary aluminium. Dense refractory bricks. Determination of cryolite resistance

The paper focuses on the determination of how periclase content in the raw material influences the final properties of no-cement refractory castables. The motivation for this research was the continued pressure on increasing the utility properties of refractory castables, especially their corrosion resistance. The influence of MgO was observed in vibration-compacted refractory castables; the mixtures were made so that the consistency of each one was the same. There were only minimal differences in the water content of the mixtures. The mineral composition of the raw materials used in the manufacturing of the refractory castables was determined and the influence of the firing temperature on their compressive strength, flexural strength, apparent porosity, mineralogy and pore structure was described. The corrosion resistance was determined by means of the crucible test according to CSN P CEN/TS 15418 (726022) Method of test for dense refractory products – Guidelines for testing the corrosion resistance of refractories caused by liquids.

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Free-Cutting Cr–Ni–Mo Steel

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.284.276 ◽

2018 ◽

Vol 284 ◽

pp. 276-280

Author(s):

A.V. Ryabov ◽

T.V. Prokaeva ◽

Yu.E. Amosova

Keyword(s):

Quality Analysis ◽

Cast Billet ◽

Medium Carbon ◽

Boron Nitrides ◽

Metallic Inclusions ◽

Inclusion Morphology ◽

Factsage Software ◽

Primary Aluminium ◽

Grade Steel

The paper presents theoretical and practical study of formation of non-metallic inclusions in a medium-carbon free-cutting structural steel. FactSage software package was used for thermodynamic modelling of inclusion behaviour. Formation temperature and the amount of aluminium oxides, boron nitrides, manganese sulphides and aluminium nitrides were calculated. Inclusions in the steel form in the sequence Al2O3 > BN > MnS > AlN. The object of practical research was a cast billet of A38KhGMAR grade steel. It was melted in a laboratory induction furnace; boron and nitrogen were introduced after deoxidation of the melt with primary aluminium. Quality analysis included determination of chemical composition, macro-and microstructure, type and shape of non-metallic inclusions. Fine and uniformly distributed boron nitride inclusions were obtained throughout the metal matrix; their distribution was studied both qualitatively and quantitatively. Beside isolated particles, boron nitrides are also presented as a component of complex inclusions with manganese sulphides. Inclusion morphology is mostly spherical. The size of BN inclusions varies from 0.41 to 7.23 μm.

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Recycling of waste refractory bricks for the production of dense refractory

Journal of Civil & Environmental Engineering ◽

10.4172/2165-784x.c1.003 ◽

2015 ◽

Vol 05 (05) ◽

Author(s):

Bahia Rabehi

Keyword(s):

Dense Refractory ◽

Refractory Bricks

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Research on corrosion mechanism of refractory lining in drip zone of COREX melting gasifier

Metallurgical Research & Technology ◽

10.1051/metal/2021032 ◽

2021 ◽

Vol 118 (3) ◽

pp. 312

Author(s):

Xiaoge Wang ◽

Pengcheng Li ◽

Huili Sun ◽

Shitao Song

Keyword(s):

Refractory Lining ◽

Protective Layer ◽

Volume Density ◽

Corrosion Mechanism ◽

Relevant Research ◽

Mechanical Erosion ◽

Refractory Bricks ◽

Slag Erosion ◽

Selection Of

In this paper, the COREX-3000 melting gasifier was dissected and sampled to obtain the macroscopic erosion appearance of refractories lining in the drip zone, and the erosion behavior and mechanism of refractory bricks in the drip zone were analyzed by means of chemical analysis, XRD, SEM and determination of physical characteristics. The results showed that the maximum average erosion of refractory lining bricks in the drip zone was 220 mm and the erosion rate was up to 69%. Its surface was mainly affected by slag erosion and mechanical scour of slag, but at high temperature, the surface of refractory could be re-sintered, forming a protective layer, which improved the volume density and high compressive strength of refractory, which was advantageous to the improvement of refractory brick slag resistance invasion and mechanical erosion resistance. Relevant research results can provide theoretical basis for the selection of refractories lining in the drip zone of COREX melting gasifier.

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