scholarly journals Possibilities of Siderite and Barite Concentrates Preparation from Tailings of Settling Pit Nearby Markušovce Village (Eastern Slovakia)

2021 ◽  
Vol 1 (1) ◽  
Author(s):  
Slavomír HREDZÁK ◽  
Silvia DOLINSKÁ ◽  
Ingrid ZNAMENÁČKOVÁ ◽  
Michal LOVAS ◽  
Oľga ŠESTINOVÁ
Keyword(s):  
Grain Size ◽  
Size Scale ◽  
Iron Concentrate ◽  
Laboratory Conditions ◽  
Magnetic Product ◽  
Material Form

The contribution deals with recovery of useful minerals such as siderite and barite from tailings collected in settling pit nearbyMarkušovce village (East Slovakia). The material form the pit was subjected to gravity pre-concentration and magnetic separationunder laboratory conditions with the aim to verify a possibility of siderite and barite concentrates preparation. A fraction of +0.2–1mm forming a 40.56 wt% of total grain size scale of the material from the pit and containing 35.71% SiO2, 22.55% Fe2O3, 7,12%Al2O3, 5.48% Ba, and 3.89% SO42– was tested in upgrading process. Thus, 78.18% of SiO2, and 60.41% of Al2O3 at loss 21.70%Fe2O3 and 2.09% of Ba were removed in gravity pre-concentration. The iron concentrate with the content of 44.33% Fe2O3 at Ferecovery of 77.29% in magnetic product was obtained. Barite pre-concentrate with the Ba content of 46.21% at Ba recovery of91.95% in non-magnetic product was won.

Studying the Influence of Tungsten and Chromium Additives in Flux Cored Wire System Fe-C-Si-Mn-Mo-Ni-V-Co on Surfaced Metal Properties

2017 ◽  
Vol 906 ◽  
pp. 107-113 ◽  
Author(s):  
I.V. Osetkovskiy ◽  
N.A. Kozyrev ◽  
R.E. Kryukov
Keyword(s):  
Grain Size ◽  
Chemical Composition ◽  
Cored Wire ◽  
Laboratory Conditions ◽  
Metal Properties ◽  
Metal Microstructure ◽  
Wire System

In the laboratory conditions were manufactured flux cored wire system Fe-C-Si-Mn-Mo-Ni-V-Co samples, studied the influence of tungsten and chromium appending in surfacing wire charge. Conducted metallographic researches of surfaced metal: microstructure evaluate, grain size, nonmetallic oxides inclusions impurity. Defined hardness and wearout speed of the deposited layers. Conducted evaluation of the chemical composition influence on surfaced metal wearout and hardness.

The Production Technology in High-Performance and Economical Hot-Rolled Ribbed Wire Rod

2013 ◽  
Vol 746 ◽  
pp. 539-542
Author(s):  
Fei Ming Xie ◽  
Yang Liu ◽  
Yan Lin Wang ◽  
Qing Zhang
Keyword(s):  
Grain Size ◽  
High Performance ◽  
Alloy Composition ◽  
Rolling Process ◽  
National Standard ◽  
Size Scale ◽  
Wire Rod ◽  
Limit Value ◽  
Steel Technology ◽  
Hot Rolled

According to the production actual situation of the hot-rolled ribbed wire rod in Fangda special steel technology Co., Ltd, Through optimizing the rolling process to improve rolling organization , and with low alloy composition, which can greatly save resources and production cost. The results show that the yield strength of hot-rolled ribbed wire rod is 510MPa, the tensile strength is 622MPa, and the elongation is 23.35%, but the content of Mn can be decreased 58.13%, the content of Si can be decreased 67.50% compared with the national standard upper limit value in HRB400; The grain size scale of edge microstructure is 9.0 at the 1# flying shear in the rolling process, the grain size scale of core microstructure is 8.5, and the edge microstructure of hot-rolled ribbed wire rod after rolling is the tempered sorbite, the grain size scale is 13.5, the core microstructure is the ferrite-pearlite, the grain size scale is 12.0, and the depth of hardening is 0.50mm.

Perfection of a technology of processing and utilization of fine fractions of dump slag

2020 ◽  
Vol 76 (6) ◽  
pp. 620-624
Author(s):  
Yu. V. Sorokin ◽  
B. L. Demin ◽  
L. A. Smirnov ◽  
Е. G. Kalimulina
Keyword(s):  
Construction Industry ◽  
Field Tests ◽  
Systematic Evaluation ◽  
Inclusion Content ◽  
Sand Mixture ◽  
Iron Concentrate ◽  
Large Yield ◽  
Magnetic Product ◽  
Basic Characteristics ◽  
Crop Capacity

Processing of old dumps slag at crushing-sorting facilities results in a large yield of slag fine fractions – screening. Because of high content of metal inclusions and powder-like fraction in the screening, this product often becomes unclaimed and is returned to dump. Magnetic separation can increase the consumer properties of the slag screening, but it is only magnetic product that is returned to the processing while the mineral part is left in the dump. Basic characteristics of 0–10 mm fraction quoted. It was determined by laboratory study, that after extraction of ferromagnetic inclusions, the true screening density decreased by 17.5% and bulk density – by 3.1%. The powder-like inclusions remain in the screening, that does not allow to consider the material as a filler for concrete and macadam-sand mixture for road-building. To recycle the magnetic product, extracted out of the screening, decreasing of slagging is needed, as well as systematic evaluation of sulphury inclusion content in it. It was proposed to divide the slag screening for macadam and sand fractions after maximum possible removal magnetic inclusions and powder-like inclusions. It will allow to return into the utilization a part of iron previously lost with the fraction 0–10 mm and to obtain an iron concentrate for sintering. The remained tails in the form of macadam of 5–10 mm fraction, sand 0–5 mm and meliorant with decreased iron content can be used in construction industry and agriculture. By field tests it was determined, that adding meliorants, which contain a grinded screening with oxides of magnesium, phosphor and microelements, into soil, results in increasing crop capacity of vegetables by 30% at test areas.

Effect of Shock Loading on the Microstructure of Uniloy 326

1974 ◽  
Vol 32 ◽  
pp. 504-505
Author(s):  
K. P. Staudhammer ◽  
L. E. Murr
Keyword(s):  
Grain Size ◽  
Shock Loading ◽  
Current Investigation ◽  
Two Phase ◽  
05 C ◽  
Shock Deformation ◽  
Heat Treated

The effect of shock loading on a variety of steels has been reviewed recently by Leslie. It is generally observed that significant changes in microstructure and microhardness are produced by explosive shock deformation. While the effect of shock loading on austenitic, ferritic, martensitic, and pearlitic structures has been investigated, there have been no systematic studies of the shock-loading of microduplex structures.In the current investigation, the shock-loading response of millrolled and heat-treated Uniloy 326 (thickness 60 mil) having a residual grain size of 1 to 2μ before shock loading was studied. Uniloy 326 is a two phase (microduplex) alloy consisting of 30% austenite (γ) in a ferrite (α) matrix; with the composition.3% Ti, 1% Mn, .6% Si,.05% C, 6% Ni, 26% Cr, balance Fe.

Aspects of microanalysis in a transmission electron microscope

1978 ◽  
Vol 36 (1) ◽  
pp. 510-511
Author(s):  
R. Sinclair ◽  
B.E. Jacobson
Keyword(s):  
Grain Size ◽  
Electron Beam ◽  
Electron Microscope ◽  
Chemical Analysis ◽  
Transmission Electron Microscope ◽  
Vapor Deposition ◽  
Critical Currents ◽  
X Ray ◽  
Fine Grain ◽  
Transmission Electron

INTRODUCTIONThe prospect of performing chemical analysis of thin specimens at any desired level of resolution is particularly appealing to the materials scientist. Commercial TEM-based systems are now available which virtually provide this capability. The purpose of this contribution is to illustrate its application to problems which would have been intractable until recently, pointing out some current limitations.X-RAY ANALYSISIn an attempt to fabricate superconducting materials with high critical currents and temperature, thin Nb3Sn films have been prepared by electron beam vapor deposition [1]. Fine-grain size material is desirable which may be achieved by codeposition with small amounts of Al2O3 . Figure 1 shows the STEM microstructure, with large (∽ 200 Å dia) voids present at the grain boundaries. Higher quality TEM micrographs (e.g. fig. 2) reveal the presence of small voids within the grains which are absent in pure Nb3Sn prepared under identical conditions. The X-ray spectrum from large (∽ lμ dia) or small (∽100 Ǻ dia) areas within the grains indicates only small amounts of A1 (fig.3).

Novel magneto-optical recording materials: Bi-substituted garnet films

1991 ◽  
Vol 49 ◽  
pp. 776-777
Author(s):  
Takao Suzuki ◽  
Hossein Nuri
Keyword(s):  
Grain Size ◽  
Amorphous Film ◽  
Nitrogen Atmosphere ◽  
Optical Recording ◽  
Garnet Film ◽  
Media Noise ◽  
Garnet Films ◽  
Order Of Magnitude ◽  
A New Technique ◽  
A Current

For future high density magneto-optical recording materials, a Bi-substituted garnet film ((BiDy)3(FeGa)5O12) is an attractive candidate since it has strong magneto-optic effect at short wavelengths less than 600 nm. The signal in read back performance at 500 nm using a garnet film can be an order of magnitude higher than a current rare earth-transition metal amorphous film. However, the granularity and surface roughness of such crystalline garnet films are the key to control for minimizing media noise.We have demonstrated a new technique to fabricate a garnet film which has much smaller grain size and smoother surfaces than those annealed in a conventional oven. This method employs a high ramp-up rate annealing (Γ = 50 ~ 100 C/s) in nitrogen atmosphere. Fig.1 shows a typical microstruture of a Bi-susbtituted garnet film deposited by r.f. sputtering and then subsequently crystallized by a rapid thermal annealing technique at Γ = 50 C/s at 650 °C for 2 min. The structure is a single phase of garnet, and a grain size is about 300A.

Structure of second phases in TiAl alloys containing Cr and B

1991 ◽  
Vol 49 ◽  
pp. 576-577
Author(s):  
Ernest L. Hall ◽  
Shyh-Chin Huang
Keyword(s):  
Grain Size ◽  
Second Phase ◽  
Structure And Properties ◽  
Tial Alloys ◽  
Second Phases ◽  
Interstitial Elements

Addition of interstitial elements to γ-TiAl alloys is currently being explored as a method for improving the properties of these alloys. Previous work in which a number of interstitial elements were studied showed that boron was particularly effective in refining the grain size in castings, and led to enhanced strength while maintaining reasonable ductility. Other investigators have shown that B in γ-TiAl alloys tends to promote the formation of TiB2 as a second phase. In this study, the microstructure of Bcontaining TiAl alloys was examined in detail in order to describe the mechanism by which B alters the structure and properties of these alloys.

Interfacial studies in Nb3Sn superconductors

1991 ◽  
Vol 49 ◽  
pp. 590-591
Author(s):  
Ernest L. Hall ◽  
Lee E. Rumaner ◽  
Mark G. Benz
Keyword(s):  
Grain Size ◽  
Grain Boundaries ◽  
Flux Pinning ◽  
Size Control ◽  
High Magnetic Fields ◽  
Type Ii ◽  
Reaction Interface ◽  
Liquid Diffusion ◽  
Type Ii Superconductor ◽  
Grain Size Control

The intermetallic compound Nb3Sn is a type-II superconductor of interest because it has high values of critical current density Jc in high magnetic fields. One method of forming this compound involves diffusion of Sn into Nb foil containing small amounts of Zr and O. In order to maintain high values of Jc, it is important to keep the grain size in the Nb3Sn as small as possible, since the grain boundaries act as flux-pinning sites. It has been known for many years that Zr and O were essential to grain size control in this process. In previous work, we have shown that (a) the Sn is transported to the Nb3Sn/Nb interface by liquid diffusion along grain boundaries; (b) the Zr and O form small ZrO2 particles in the Nb3Sn grains; and (c) many very small Nb3Sn grains nucleate from a single Nb grain at the reaction interface. In this paper we report the results of detailed studies of the Nb3Sn/Nb3Sn, Nb3Sn/Nb, and Nb3Sn/ZrO2 interfaces.

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