Effect of B2O3 on the Sintering Process of Vanadium–Titanium Magnet Concentrates and Hematite

This work studied the effect of B2O3 (analytical reagent) on the parameters of a sintering pot test, as well as the metallurgical properties and microstructure of the sinter samples, to determine the feasibility of applying solid waste containing B2O3 in vanadium–titanium sintering. The results show that along with B2O3 addition, the mechanical strength of the sinter first increases and then decreases; the maximum strength was found upon the addition of 3.0% of B2O3. The low-temperature reduction and pulverization rate of the vanadium–titanium sinter were also improved, while the start and end temperatures of softening showed a decreasing trend. The microstructure of the sinter was found to change from plate structure to particle and point structure, with uniformly distributed small areas. The sintering pots created by B2O3 addition had low total porosity but a greater pore diameter than pots created without the reagent.

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Fabrication and Characterization of Alumina/Zirconia Ceramic Compound

Materials Science Forum ◽

10.4028/www.scientific.net/msf.724.249 ◽

2012 ◽

Vol 724 ◽

pp. 249-254 ◽

Cited By ~ 1

Author(s):

Bum Rae Cho ◽

Ji Hoon Chae ◽

Bo Lang Kim ◽

Jong Bong Kang

Keyword(s):

Mechanical Properties ◽

Fracture Toughness ◽

Low Temperature ◽

Mechanical Strength ◽

Sem Analysis ◽

Zirconia Ceramic ◽

Sintering Process ◽

Sintering Aids ◽

X Ray Diffraction

Sintered ZTA(zirconia toughened alumina) which has good mechanical properties at a low temperature was produced by milling and mixing with Al2O3 and ZrO2(3Y-TZP). In order to examine the effect of sintering aids on the mechanical properties of ZTA, fracture toughness and hardness of the produced ZTA were observed in accordance with change of the added quantity of ZrO2 Scanning electron microscopy and X-ray diffraction technique were applied to observe microstructural change and phase transformation during the process. Experimental results showed that the addition of sintering aids in ZTA at a low temperature induced densification and adding SiO2 and talc lowered sintering temperature and promoted crystallization process of the compound. The mechanical strength of ZTA added ZrO2 showed higher mechanical strength and SEM analysis revealed that Al2O3 and ZrO2 during the sintering process restrained the grain growth each other. Especially, the 92% Al2O3 added sintering aids showed more than 98% of the theoretical density and more than 1500 Hv of hardness value at a low temperature of 1400. It was also showed that the fracture toughness is gradually increasing first and decreasing later in accordance with the quantity of ZrO2.

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The Influence of Gum Arabic Admixture on the Mechanical Properties of Lime-Metakaolin Paste Used as Binder in Hemp Concrete

Materials ◽

10.3390/ma14226775 ◽

2021 ◽

Vol 14 (22) ◽

pp. 6775

Author(s):

Przemysław Brzyski

Keyword(s):

Mechanical Properties ◽

Compressive Strength ◽

Mechanical Strength ◽

Pore Diameter ◽

Gum Arabic ◽

Total Porosity ◽

Hydrated Lime ◽

Partial Replacement ◽

Reference Formulation ◽

Strength Parameters

Organic admixtures based on polysaccharides are used in construction for modifying the properties of mortars and concretes. Gum arabic is an example of a polysaccharide-based biopolymer. The aim of the article was to investigate the possibilities of improving the strength parameters of a binder paste based on hydrated lime and metakaolin. The paste was modified with powdered gum arabic at 1%, 3% and 5% (by mass) as a partial replacement for the binder mix. The influence of the admixture on the pore size distribution as well as flexural and compressive strength was investigated. The admixture enhanced the total porosity of the paste, increasing the pore diameter compared with the reference formulation. The increase in porosity, in turn, did not reduce the mechanical strength. Conversely, the admixture in the amount of 3% and 5% caused a significant increase in the flexural (by about 300% in relation to reference paste) and compressive strengths (by 25% and 60%, respectively). The tested pastes were used as a binder in a composite based on hemp shives. The influence of binder modification on the water absorption and compressive strength of hemp concrete was tested. The strength of the composite soaked in water was also tested. The modification of the binder with gum arabic in the amount of 3% and 5% increased the compressive strength of hemp concrete (not soaked in water) by 53% and 92%, respectively and reduced the mass absorptivity by 6.6% and 10.4%, respectively.

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Experimental Study on Oxygen-Enriched Sintering of Vanadium-Titanium Magnetite

Journal of Chemistry ◽

10.1155/2018/9342760 ◽

2018 ◽

Vol 2018 ◽

pp. 1-9 ◽

Cited By ~ 1

Author(s):

Hao Liu ◽

Yuelin Qin ◽

Xinlong Wu ◽

Bing Xie

Keyword(s):

Low Temperature ◽

Ignition Temperature ◽

Oxygen Enrichment ◽

Sintering Process ◽

Temperature Reduction ◽

Utilization Coefficient ◽

Coefficient Increase ◽

Vanadium Titanium ◽

Titanium Magnetite ◽

Low Temperature Reduction

The influences of various factors, such as oxygen enrichment time, oxygen enrichment load, and ignition temperature, on the technical indices and sintering performance in the vanadium-titanium magnetite sintering process are simulated using sinter pot experiments. The experiments are based on the field production parameters of a sintering trolley in a steel enterprise in southwest China. Prolonged oxygen enrichment time results in the gradual increase in vertical sintering speed, sintering utilization coefficient, sintered ore yield, sintered ore drum strength, and reductivity. However, the low-temperature reduction pulverability of the sintered ore deteriorates. Oxygen enrichment load increases from 0 m3/h to 2.9 m3/h, and yield increases by 1.1%, while the vertical sintering speed and utilization coefficient increase slightly. Sintered ore drum strength increases from 65.33% to 68.00%, antiwear index decreases to 0.47%, and low-temperature reduction pulverability decreases from 65.07% to 62.85%. The increased ignition temperature is beneficial to improve the drum strength and yield of the ore but reduces the vertical sintering speed and utilization coefficient. With the increase in ignition temperature, the low-temperature reduction pulverability tends to increase first and then decrease. Changes in oxygen time, oxygen enrichment load, and ignition temperature have no significant effects on the soft melting performance of the sintered ore.

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BOFORS 2RM2

Alloy Digest ◽

10.31399/asm.ad.ss0169 ◽

1965 ◽

Vol 14 (5) ◽

Keyword(s):

Fracture Toughness ◽

Corrosion Resistance ◽

Low Temperature ◽

Mechanical Strength ◽

Physical Properties ◽

Tensile Properties ◽

Cast Steel ◽

Heat Treating ◽

High Mechanical Strength ◽

Temperature Performance

Abstract BOFORS 2RM2 is a hardenable stainless cast steel having good weldability, high mechanical strength and improved corrosion resistance. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties as well as fracture toughness. It also includes information on low temperature performance and corrosion resistance as well as casting, forming, heat treating, machining, and joining. Filing Code: SS-169. Producer or source: Aktiebolaget Bofors.

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