scholarly journals Crystallization temperatures of complex ferroalloys

2020 ◽  
Vol 63 (7) ◽  
pp. 568-570
Author(s):  
O. V. Zayakin ◽  
D. S. Renev

Thermo-gravimetric method was used to determine the temperature of crystallization onset of alloys of the Fe – Ni – Cr – C – Si system depending on concentration of chromium and nickel. It was shown that complex ferroalloys containing 0.2 – 21.0 % Ni (at Cr = 25 – 28 %); 0.5 – 45.0 % Cr (at Ni = 10 – 11 %); 2.0 % C and 0.3 % Si, iron, and impurities belong to the category of low-melting alloys and have rational values (1320 – 1400 °C) of crystallization temperatures in terms of their use for steel processing in the ladle. An increase of the chromium content to more than 45 % in these alloys is accompanied by an intense increase of their temperatures of the crystallization onset.

2012 ◽  
Vol 538 ◽  
pp. 55-62 ◽  
Author(s):  
Sergey P. Verevkin ◽  
Ricardas V. Ralys ◽  
Dzmitry H. Zaitsau ◽  
Vladimir N. Emel’yanenko ◽  
Christoph Schick

2016 ◽  
Vol 246 ◽  
pp. 63-66
Author(s):  
Janusz Węgrzyn ◽  
Bolesław Machulec

The most objective methods of determining the usefulness of quartzite for the ferrosilicon smelting process are industrial research methods, but such studies are long-lasting and costly. In order to test the usefulness of thermo-gravimetric method to evaluate technological properties of quartzites in a laboratory, thermo-gravimetric studies of quartzites samples from various deposits were carried out. These quartzites are used or were used as a raw material in industrial ferrosilicon process. The study consisted of measuring the weight loss of powder samples in the form of mixture of quartz with graphite of molar ratio SiO2 + 3C during heating under an argon atmosphere in the temperature range up to 1500°C. The evaluation of technological properties of quartzites was done by comparing the curves of relative weight loss with industrial technological data of the ferrosilicon smelting process. It was established that the results of thermo-gravimetric studies show satisfying agreement with observations of industrial process, whereas quartzites of improved technological properties revealed a lower weight loss in thermo-gravimetric studies. Studies of this type can be useful as one of the methods of objective assessment of usefulness of quartzites for the ferrosilicon smelting process.


Author(s):  
L.E. Murr ◽  
J.S. Dunning ◽  
S. Shankar

Aluminum additions to conventional 18Cr-8Ni austenitic stainless steel compositions impart excellent resistance to high sulfur environments. However, problems are typically encountered with aluminum additions above about 1% due to embrittlement caused by aluminum in solid solution and the precipitation of NiAl. Consequently, little use has been made of aluminum alloy additions to stainless steels for use in sulfur or H2S environments in the chemical industry, energy conversion or generation, and mineral processing, for example.A research program at the Albany Research Center has concentrated on the development of a wrought alloy composition with as low a chromium content as possible, with the idea of developing a low-chromium substitute for 310 stainless steel (25Cr-20Ni) which is often used in high-sulfur environments. On the basis of workability and microstructural studies involving optical metallography on 100g button ingots soaked at 700°C and air-cooled, a low-alloy composition Fe-12Cr-5Ni-4Al (in wt %) was selected for scale up and property evaluation.


2018 ◽  
Vol 2 (2) ◽  
Author(s):  
SULASMI ANGGO

The Analysis of physical chemical from dara shells (Anadara granosa) origin from Kayutanyo, kab. Banggai, has been conducted.Dara shell meat is sleaned and dried and after that powered with blender. Determine % rendement, water bonding capacity and index water solubility with Anderson method, coarse fat content with gravimetric method and carbohydrate method with “bye difference” decrease method.The result of analysis showed rendement value is 24,35%, water bonding capacity is 1,6248 gram/ml, index water solubility is 0,202 gram/ml, water content is 79,0045%, total dust content is 1,072%, coarse protein content is 2,25%, coarse fat content is 8,47%, carbohydrate content is 9,2035%. Keyword : Dara shells, (Anadara granosa), analysis physical chemical


Author(s):  
S. Bharati ◽  
B. Patil ◽  
H. Vishwanath ◽  
P. Hittalamani ◽  
S. Joshi

Author(s):  
G. Suresh ◽  
K. Sambath Kumar ◽  
P. Ambalavanan ◽  
P. Kumaresan

Zinc Thiourea Sulphate (ZTS), crystal is a magnificent metal natural compound, which consolidates the upsides of both natural and inorganic materials when contrasted and other customary non-linear optical materials and in this way can be utilized as a part of a more extensive scope of uses. Late endeavors at delivering new recurrence transformation materials have concentrated essentially on expanding the extent of the NLO properties that can recurrence twofold low pinnacle control sources, for example, diode lasers.  The thermo gravimetric examination (TGA) and differential warm investigation (DTA) were completed utilizing Seiko warm analyzer at warming rate 20°C/min in air to decide the warm dependability of the compound. ZTS crystals were developed by moderate cooling procedure. This empowers the development of mass gems along all the three bearings at an ideal pH. FTIR examines demonstrate that in the spectra of ZTS there is a move in the recurrence band in the low-recurrence district which uncovers that thiourea shapes sulfur-to-zinc securities in the ZTS crystals. The stability and charge delocalization of the molecule were also studied by natural bond orbital (NBO) analysis. The HOMO-LUMO energies describe the charge transfer takes place within the molecule. Molecular electrostatic potential has been analyzed.  The developments try in extensive scale with this enhanced pH qualities is required to yield mass crystal appropriate for laser combination tests and SHG device applications.


2018 ◽  
Vol 5 (2) ◽  
pp. 16-18
Author(s):  
Chandar Shekar B ◽  
Ranjit Kumar R ◽  
Dinesh K.P.B ◽  
Sulana Sundar C ◽  
Sunnitha S ◽  
...  

Thin films of poly vinyl alcohol (PVA) were prepared on pre-cleaned glass substrates by Dip Coating Method. FTIR spectrum was used to identify the functional groups present in the prepared films. The vibrational peaks observed at 1260 cm-1 and 851 cm-1 are assigned to C–C stretching and CH rocking of PVA.The characteristic band appearing at 1432 cm-1 is assigned to C–H bend of CH2 of PVA. The thickness of the prepared thin films were measured by using an electronic thickness measuring instrument (Tesatronic-TTD20) and cross checked by gravimetric method. XRD spectra indicated the amorphous nature of the films.Surface morphology of the coated films was studied by scanning electron microscope (SEM). The surface revealed no pits and pin holes on the surface. The observed surface morphology indicated that these films could be used as dielectric layer in organic thin film transistors and as drug delivery system for wound healing.


2019 ◽  
Author(s):  
Chem Int

The corrosion inhibition characteristics of two medicinal molecules phenylalanine and rutin on mild steel in 1.0M Hydrochloric acid were evaluated using gravimetric method. Corrosion inhibition efficiency of 83.78 and 90.40 % was obtained respectively after seven days. However, phenylalanine showed weak accumulative higher corrosion inhibition efficiency. The presence of both molecules in the corrosive environment reduced the corrosion rate constant and increased the material half-life. Thermodynamic data calculated suggests a spontaneous adsorption of the molecules on the mild steel’s surface.


Sign in / Sign up

Export Citation Format

Share Document