Development for the production of low phosphorus steel in operations at Arcelor Mittal Tubarão

In this study, double-slag method is used to melt low-phosphorous steel by semi-steel. The results show that, the average phosphorous content of the aimed molten iron of BOF is 0.0052% and after the first slag pure-out, the dephosphorization rate is 56.2%, while the total dephosphorization rate of BOF melting is 92.46%, rang from 91% to 93.4%. Low phosphorous content alloy and slag-stopping tapping technology is adopted and rephosphorization of molten iron is controlled in 0.002%. Finally the average phosphorous of the finished product is 0.0064%, range form 0.0055% to 0.0071%, which means that Pangang Group can produce the steel with phosphorous content is less than 0.008%.

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Double slag operation dephosphorization in BOF for producing low phosphorus steel

Journal of Iron and Steel Research International ◽

10.1016/s1006-706x(09)60036-4 ◽

2009 ◽

Vol 16 (3) ◽

pp. 6-14 ◽

Cited By ~ 20

Author(s):

Zhi-hong Tian ◽

Ben-hai Li ◽

Xiao-ming Zhang ◽

Zhong-hang Jiang

Keyword(s):

Low Phosphorus ◽

Phosphorus Steel ◽

Double Slag

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Dephosphorization by Double-Slag Process in Converter Steelmaking

High Temperature Materials and Processes ◽

10.1515/htmp-2016-0250 ◽

2018 ◽

Vol 37 (7) ◽

pp. 625-633

Author(s):

Yang Wang ◽

Shufeng Yang ◽

Jingshe Li ◽

Jie Feng ◽

Feng Wang

Keyword(s):

Production Efficiency ◽

Smelting Process ◽

Converter Steelmaking ◽

Steelmaking Process ◽

Key Factors ◽

Iron Slag ◽

Low Phosphorus ◽

Dephosphorization Slag ◽

Phosphorus Steel ◽

Double Slag

AbstractThe double-slag converter steelmaking process can smelt low- and ultra-low-phosphorus steel and reduce lime and dolomite consumption and the amount of final slag simultaneously. Industrial steelmaking tests on a 150-metric ton converter at the Tangsteel Company were carried out to study this principle and its effect on the dephosphorization ratio and material consumption. The results showed that low-temperature stage could be used with a reduced amount of slag in the double-slag steelmaking process to achieve rapid and efficient dephosphorization. A low-basicity slag (~1.5–2.0) in the dephosphorization stage is required in double-slag process. The dephosphorization ratio reached a maximum of 71 % when the slag basicity was 1.7. The end-point phosphorus content after the smelting process was reduced from an average of 0.018 mass% to an average of 0.011 mass% and the dephosphorization efficiency increased by more than 6 %. The dephosphorization slag could be poured out rapidly when the FeO content was controlled at ~16–20 mass% in the double-slag smelting process. Based on key factors such as an efficient dephosphorization and a rapid iron–slag separation, the production efficiency was improved and the smelting cycle increased by only four minutes over the conventional process.

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Mechanical properties of low alloy high phosphorus weathering steel

Journal of Mining and Metallurgy Section B Metallurgy ◽

10.2298/jmmb140120005j ◽

2015 ◽

Vol 51 (1) ◽

pp. 81-87

Author(s):

B.K. Jena ◽

N. Gupta ◽

B. Singh ◽

G.S. Ahoo

Keyword(s):

Phosphorus Content ◽

Weathering Steel ◽

Low Alloy Steels ◽

Percentage Elongation ◽

Brittle Rupture ◽

Ductile Mode ◽

Low Phosphorus ◽

Optical Photomicrograph ◽

Alloy Steels ◽

Phosphorus Steel

Mechanical behaviour of two low alloy steels (G11 and G12) was studied with respect to different phosphorus contents. Tensile strength and yield strength increased while percentage elongation at fracture decreased on increasing phosphorus content. The SEM and light optical photomicrograph of low phosphorus steel (G11) revealed ferrite and pearlite microstructure. On increasing phosphorus content from 0.25 wt.% to 0.42 wt.%, the morphology of grain changed from equiaxed shape to pan-cake shape and grain size also increased. The Charpy V notch (CVN) impact energy of G11 and G12 steel at room temperature was 32 J and 4 J respectively and their fractographs revealed brittle rupture with cleavage facets for both the steels. However, the fractograph of G11 steel after tensile test exhibited ductile mode of fracture with conical equiaxed dimple while that of G12 steel containing 0.42 wt. % P exhibited transgranular cleavage fracture. Based on this study, G11 steel containing 0.25 wt. % P could be explored as a candidate material for weathering application purpose where the 20?C toughness requirement is 27 J as per CSN EN10025-2:2004 specification.

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Inter Layer Dielectric Defect Induced High Contact Resistance

ISTFA 2010: Conference Proceedings from the 36th International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa2010p0054 ◽

2010 ◽

Author(s):

Re-Long Chiu ◽

Jason Higgins ◽

Toby Kinder ◽

Juha Tyni ◽

Sharon Ying ◽

...

Keyword(s):

Contact Resistance ◽

Failure Analysis ◽

Failure Mode ◽

Phosphorus Content ◽

Moisture Absorption ◽

Thermal Processes ◽

Analysis Methods ◽

Low Phosphorus

Abstract High contact resistance can be caused by moisture absorption in low phosphorus content BPTEOS. Moisture diffused through the TiN glue layer is absorbed by the BPTEOS during subsequent thermal processes resulting in increased contact resistance. This failure mode was studied by combining different failure analysis methods and was confirmed by duplication on experimental wafers.

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Photosynthetic and yield traits identified through multivariate analysis in mungbean exhibiting tolerance to the combined stresses of low phosphorus and drought

Indian Journal of Genetics and Plant Breeding (The) ◽

10.31742/ijgpb.80.3.8 ◽

2020 ◽

Vol 80 (03) ◽

Author(s):

Renu Pandey ◽

Surendra Kumar Meena ◽

Gayacharan . ◽

Madan Pal Singh

Keyword(s):

Canopy Temperature ◽

Principal Component ◽

Relative Increase ◽

Photosynthetic Parameters ◽

Combined Stresses ◽

P Content ◽

Low Phosphorus ◽

Relative Stress ◽

Relative Water ◽

Component Traits

Experiments were conducted to study the genotypic variability for tolerance to combined stresses of low availability of phosphorus (P) and drought in 14 mungbean [Vigna radiata (L.) R. Wilczek] accessions. The accessions were evaluated under four conditions viz., control (sufficient P, irrigated), low P (without P, irrigated), drought (sufficient P, withholding irrigation) and combined stresses (low P, withholding irrigation). The relative stress tolerance was estimated for 22 agro-physiological traits. The principal component analysis (PCA) and relative stress indices (RSIs) of traits exhibited significant variation among the treatments and accessions. Based on RSIs, the PCA ranking analysis showed that the accessions IC 280489, PDM 139 and IC 76491 were highly ranked and tolerant to low P, drought and combined stresses. The relative increase in component traits such as photosynthetic parameters, relative water content, above-ground biomass, seed P content and number of pods plant–1 were higher while canopy temperature and water use efficiency were reduced in tolerant accessions. In contrast, IPM 2-3 was found to be relatively sensitive to all three treatments. Tolerant accessions may be either included in the breeding program or used directly as cultivar that can be grown under low P and drought.

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