Ioan PETEAN

32-37 CONTACTE ELECTRICE CU DENSITATE RIDICATĂ PENTRU CURENŢI INTENŞI PRODUSE PRIN METALURGIA PULBERILOR

Această intrare a fost publicată în 2017 Volumul 32 și etichetată Adrian ARDUSĂTAN Alina Georgeta JUMOLEA George ARGHIR Ioan PETEAN Liviu BRÂNDUŞAN Marius BĂRĂIAN Gabriel BATIN Nicu Marian TRANDAFIR la de

ELECTRICAL CONTACTS WITH HIGH DENSITY FOR STRONG CURRENTS, MADE BY POWDER METALLURGY

 

Electrical contacts for strong currents by infiltration after sintering, was not satisfactory because the final density is much higher (11,100 kg/m3) and porosity is much lower (10.85 %). The infiltration after sintering contains: powder mixture preparation (W – 52 mass %, Ni – 2 %, Cu – 46 %, zinc stearate – 0,7 %  – 7 g), homogenization, pressing (4,5 MPa), sintering (730 and 780 oC). The green density is almost constant, with an identical porosity of the first after the end of the process (14,28 %). By infiltration the density increased drastically (10,832 kg/m3), its variations were increased also and porosity decreased (at 10.85 %). The attained density is not sufficient for electrical contacts work (11,100 kg/m3), but it is closer. Way to improve density: pressing, sintering, and repressing (10,700 kg/m3).

 

Keywords: sintered electrical contacts, W-Cu

Cuvinte cheie: contacte electrice sinterizate, W-Cu

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30-16 CONTACTE ELECTRICE PENTRU CURENŢI INTENŞI PRODUSE PRIN METALURGIA PULBERILOR

Această intrare a fost publicată în 2016 Volumul 30 și etichetată Gabriel BATIN George ARGHIR Ioan PETEAN Liviu BRÂNDUŞAN Marius BĂRĂIAN la de

ELECTRICAL CONTACTS FOR STRONG CURRENTS
MADE BY POWDER METALLURGY
It was tested to be produced electrical contacts for strong currents by
infiltration after sintering, because the final density is much higher (11.100
kg/m3) and porosity is much lower (10.85 %). The infiltration after sintering
variant contains the steps: powder mixture preparation (W – 52 mass % – 520 g,
Ni – 2 mass % – 20 g, Cu – 46 mass % – 460 g, zinc stearate – 0,7 mass % – 7
g), homogenization, pressing (4.5 MPa), sintering (730 and 780 oC) and
infiltration (the green part is layed down on an electrocorindon EC 120 bed,
then the Cu green is on top of it, 1100 oC). In this variant the green part density
is almost constant (s = 0.062), with an identical porosity of the first after the end
of the process (14,28 %). By infiltration the density increased drastically (at
10,832 kg/m3), but its variations were increased also (s = 0.174) and porosity
decreased (at 10.85 %). The attained density is not sufficient for electrical
contacts work (11,100 kg/m3), but it is closer. The final composition of the
electrical contact was: W – 48.69 mass %, Ni – 1. 87 mass % and Cu – 49.44
mass %.
Keywords: sintered electrical contacts, W-Cu
Cuvinte cheie: contacte electrice sinterizate, W-Cu

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27-23 ASPECTE PRIVIND PRELUCRAREA OSHIBANA A FLORILOR DIN CATEGORIA ERYTHRONIUM DENS CANIS

Această intrare a fost publicată în 2015 Volumul 27 și etichetată Alexandra Gertrud HOSU – PRACK George ARGHIR Ioan PETEAN la de

ASPECTS REGARDING OSHIBANA PROCESSING OF
ERYTHRONIUM DENS CANIS FLOWERS
Erythronium Dens Canis is a spring flower with high visual impact due to its petal disposing as a radiate crown in the early stage and as an open dog mouth in the later stage. The visual effect is enhanced by stamina position in the centre of the flower. Such nice flower worth’s to be processed by Oshibana method. We collect several flowers from Faget Woods nearby Cluj Napoca, Romania, in several development stages: bloom, early opened flower and mature opened (late) stage. All were pressed according to the best option: large numbers of paper pages between flower layers and average loading of around 3 kg uniform distributed over an A4 page format. The optical microscopy evidence a good pressing of the petals with a good cohesion among cellular walls. The final test shows that the Erytronium Dens Canis pressed flowers are suitable for Osibana compositions.
Keywords: Oshibana, Erythronium Dens Canis
Cuvinte cheie: Oshibana, Erythronium Dens Canis

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25-17 UNELE ASPECTE INGINEREŞTI PRIVIND ARTA OSHIBANA

Această intrare a fost publicată în 2014 Revista Volumul 25 și etichetată Alexandra Gertrud HOSU – PRACK George ARGHIR Ioan PETEAN la de

SOME ENGINEERING ASPECTS REGARDING
OSHIBANA ART
The pressed flower art, Oshibana, was developed by japans samurai
centuries ago. This art found followers in Romania, some of them being
Oshibana Maestro Artist. Inspired by them we found that some basic
engineering aspects are beyond the success in the flower pressing process.
The authors of this paper aim to practice these engineering aspects on the
vegetal material to obtain suitable Oshibana parts. We use petals from the
following flowers: yellow rose (Rosa L.), red carnation (Dianthus Caryophyllus),
and violet crocus (Crocus Vernus). The resulted pressed petals were
investigated with transmitted light optical microscope. The petals fibber network
was observed as well as the pigment alveoli. The petal cohesion under
pressure is assured by the cellulose fibres meanwhile the intracellular liquid is
absorbed by the press paper pages, finally the petal cells become flat and dry.
The pigment alveoli were distinct observed for all samples. Their diameter is
significantly increased under pressure ranging from 30 – 40 μm. The flattening
tendency is prone at Crocus and Dianthus and less intense at the Rose petal.
Keywords: pressed flowers, Oshibana, optical microscopy
Cuvinte cheie: flori presate, oshibana, microscopie optică
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17-39 INVESTIGAłII STRUCTURALE PRIVIND COMPOZIłIA ANTONINIENILOR ROMANI SUBERAłI

Această intrare a fost publicată în 2010 Volumul 17 și etichetată George ARGHIR Ioan PETEAN la de

STRUCTURAL INVESTIGATION CONCERNING THE
COMPOSITION OF FOUREE ROMAN ANTONINIAN
The antoninians were issued for the first time by Emperor Caracalla in
year 215 as a monetary reform. It was minted as double denar denomination in
order to preserve the silver title. The silver title and coin weight decrease soon
due to inflation. The fouree antoninians were issued at large scale by Emperor
Aurelianus featuring on the coin obverse the XXI inscription. The structural
investigation performed on some fouree antoninians issued by Aurelian,
Probus, and Diocletian, shows copper as coin core and the related corrosion
oxides compounds related to the loss of the silver foil due to the ground
corrosion. The calculation prove that the foil silver amount represents one part
silver to twenty copper parts, meaning that inscription XXI on the coin obverse
is an official silver title mark. The continuous decaying of antoninians quality
lead to a monetary reform after Diocletian reign.
Cuvinte cheie: antoninieni romani, patina, structura, difracŃie cu raze X

39 INVESTIGAłII STRUCTURALE PRIVIND COMPOZIłIA

19-78 DISTRIBUŢIA MINERALELOR ÎN CENUŞA DE HUILĂ DE LA TERMOCENTRALA PAROŞENI

Această intrare a fost publicată în 2011 Volumul 19 și etichetată Alexandra Gertrud HOSU – PRACK Andreea BRAŞOVAN George ARGHIR Ioan PETEAN Ramona Flavia CÂMPEAN Vlad CODREA la de

MINERALS DISTRIBUTION IN COAL FLY ASH FROM
PAROSENI POWER PLANT
Large ash dumps, formed in time, are a high harmful potential for
environment. Our study points out the mineral contained in fly ash resulted at
Paroşeni power plant. The X-ray diffraction analysis reveals large amounts of
quartz, mullet, potasic feldspar, Seri cite and hydrated hematite. Microscopy
investigation prove that quartz particles keeps their initial equiaxial shape
meanwhile higher amount of mullet and hematite feature spherical shape due
to their melting during coal burning. The quantitative microscopic analysis
reveals three particles domains: the larger one having the average diameter of
100 μm, the intermediary one having the average diameter of 44 μm, and the
finest one having the average diameter of 23 μm. Quartz particles are often
found in the larger particle range, hematite hydrate and mullet are often found
in the intermediary particle range, meanwhile feldspar and Seri cite are situated
mainly in the finest particle range.
Keywords: ash, coal, power plant
Cuvinte cheie: cenuşă, huilă, termocentrală

78 DISTRIBUŢIA MINERALELOR ÎN CENUŞA DE HUILĂ

20-50 APLICABILITATEA LEGII VEGARD ÎN DETERMINAREA PARAMETRULUI CRISTALOGRAFIC LA PULBERILE ALIATE MECANIC

Această intrare a fost publicată în 2011 Volumul 20 și etichetată Dan Anastasiu POP George ARGHIR Ioan PETEAN la de

VEGARD LAW APLICABILITY IN CRYSTAL PARAMETER
DETERMINATION FOR MECHANICALLY ALLOYED
POWDERS
The performed investigations prove that applying the Vegard Law for
Cr-Fe binary alloys result values of crystal parameter in good concordance with
experimental results. This makes Vegard Law a useful theoretical tool for
estimation of crystal properties of further alloys. The viability of this law could
not be proved for ternary systems. We mention that Al and Co were introduced
as ternary component after 16 hours of previous milling of Fe-Cr powder
composition. The adding of ternary element such Al or Co at the beginning of
milling experiment is an open path for further investigation of the applicability of
Vegard Law to the ternary systems.
Keywords: Fe-Cr alloys, lattice parameter, solid solutions
Cuvinte cheie: aliaje Fe-Cr, parametru reţelei cristaline, soluţii solide

50 APLICABILITATEA LEGII VEGARD ÎN

20-55 TRANSFORMĂRI STRUCTURALE ALE OŢELULUI LEDEBURITIC X200Cr12 ÎN URMA APLICĂRII UNUI TRATAMENT TERMIC ŞI CRIOGENIC

Această intrare a fost publicată în 2011 Volumul 20 și etichetată George ARGHIR Ioan PETEAN Marius BĂRĂIAN Nicolaie JUMATE la de

STRUCTURAL TRANS FORMATIONS
OF THE X200Cr12 LEDEBURITIC STEEL AFTER A
CRYOGENIC HEAT TREATMENT
Cryogenic treatment completes the classic heat treatment of steels
with higher carbon content of 0.6 %, bringing substantially improving on
properties, being very simple.
In the case of X200Cr12 ledeburitic steel, the amount of residual
austenite was reduced from 20.03 % to 14.14 %, being transformed into
martensite, as a result of cryogenic treatment done immediately after
quenching.
Hardness Vickers values were increased with 61 units, representing a
6.7 % increase, as a result of martensitic transformation.
Keywords: steel ledeburitic X200Cr12, X-ray diffraction, martensitic
transformation, optical microscopy, low temperature
Cuvinte cheie: oţel ledeburitic X200Cr12, difracţie cu raze X,
transformare martensitică, microscopie optică, temperaturi scăzute

55 TRANSFORMĂRI STRUCTURALE ALE OŢELULUI

20-56 ASPECTE MORFOLOGICE ŞI STRUCTURALE ALE AMESTECULUI PULVERULENT Fe50Ni50 SUPUS ALIERII MECANICE

Această intrare a fost publicată în 2011 Volumul 20 și etichetată George ARGHIR Ioan PETEAN Ioan TĂUT la de

MORPHOLOGICAL AND STRUCTURAL ASPECTS
OF Fe50Ni50 POWDER MIXTURE SUBJECTED TO
MECHANICAL ALLOYING
The mechanical alloying experiment was performed inti a planetary
ball mill using elemental Fe and Ni powders mixed together at 50 wt. % ratio.
Powder samples were taken out after 1, 2, 4, 8, 16, 32, 48, and 64 hours of
milling. These samples were subjected to X-ray diffraction, sieving analysis,
and optical microscopy inspection. The results allow us to conclude that Ni
presents a ductile behaviour meanwhile Fe acts as a brittle component which
conducts to the forming of mixed particles of Ni embedding smaller Fe one. The
particle structure is more refined progressive with the milling time. Finally, the
solid solution of Fe in Ni FCC is completely formed at 64 hours of milling.
Keywords: Fe-Ni, alloy mechanical, planetary mill
Cuvinte cheie: Fe-Ni, aliere mecanică, moară planetară

56 ASPECTE MORFOLOGICE ŞI STRUCTURALE

23-27 INVESTIGAREA COMPOZIȚIEI UNEI MOSTRE DE TENCUIALĂ VECHE

Această intrare a fost publicată în 2013 Volumul 23 și etichetată Alexandra Gertrud HOSU – PRACK George ARGHIR Ioan PETEAN Marius BĂRĂIAN la de

THE INVESTIGATION OF AN OLD
PLASTER SAMPLE
Wall plasters are featured since the first buildings are raised. They are
often found in Roman Empire for many applications such walls and hypocaust
structure. One of the main components in such plasters is broken brick. We
found broken brick in a usual plaster dating from 1950, along with quartz,
calcite, kaolinite, and portlandite. We can affirm that the investigated plaster
sample is more similar to the roman plasters than to the modern one.
Cuvinte cheie: tencuială, difracţie cu raze X
Keywords: surface-mounted, x-ray diffraction

23-27 INVESTIGAREA COMPOZIȚIEI UNEI MOSTRE

21-73 DATE PRIVIND MINERALOGIA STERILULUI REZULTAT ÎN URMA SPĂLĂRII HUILEI LA PREPARAŢIILE DIN VESTUL BAZINULUI PETROŞANI

Această intrare a fost publicată în 2012 Volumul 21 și etichetată Andreea BRAŞOVAN George ARGHIR Ioan PETEAN Vlad CODREA la de

DATA CONCERNING THE MINERALOGY OF STERILE
RESULTED FROM PIT COAL WASHING AT WESTERN
PETROSANI BAZIN PREPARATIONS
The mineral composition of the sterile dumps formed during coal
exploitation and sorting was established during this research. There are found
quartz, potassium feldspar, biotite and calcite. The X-ray diffraction analysis
point out these minerals as well as pronounced crystalline state of the dumped
sterile. The optical mineralogical microscopy reveals the sterile particles
morphology, equiaxial for quartz and calcite and tabular – philliphorm for the
biotite and potassium feldspar. All issued minerals belong to the non coal
intercalations on the geological coal layers.
Cuvinte cheie: steril, huilă, preparaţie
Keywords: sterile, coal, preparation

73 DATE PRIVIND MINERALOGIA STERILULUI REZULTAT

21-30 ASPECTE PRIVIND COMPOZIŢIA PATINEI UNOR MONEDE ROMANE DE BRONZ

Această intrare a fost publicată în 2012 Volumul 21 și etichetată George ARGHIR Ioan PETEAN la de

ASPECTS CONCERNING THE COMPOSITION OF SOME
BRONZE ROMAN COINS PATINA
The earlier roman bronze denominations, such as and sestertius, were
stroked in bronze (Cu Sn binary alloy). The coinage title decreases on the later
Roman Empire, silver denarius were finally replaced by the copper follies. The
X-ray diffraction analysis of such coins surface allows us to identify the rust
compounds. We found that on the bronze coins surface are developed mainly
copper oxides, hydroxides as well as tin oxide. We also reach a complex CuSn
hydroxide which gives a greenish yellow shade of the patina. The green hue of
patina is significant enhanced by the average of copper carbonate content also
found as a patina component. The copper foils feature only copper oxides and
hydroxides without carbonates. It proves that the investigated follies laid in a
more inert soil (e.g. quartz sand). The colour of patina is dark brown to shiny
black due to the refined mixture of copper oxides and hydroxide. Some quartz
traces were identified on the coins surfaces as residues of soil. The performed
analysis gives important data useful for modern fake’s identification.
Cuvinte cheie: patină, structură, difracţie cu raze X
Keywords: skate, structure, X-ray diffraction

30 ASPECTE PRIVIND COMPOZIŢIA PATINEI UNOR

22-34 ASPECTE STRUCTURALE ALE AMESTECURILOR PULVERULENTE Fe60Ni40, Fe50Ni50, Fe40Ni60 SUPUSE ALIERII MECANICE

Această intrare a fost publicată în 2012 Volumul 22 și etichetată George ARGHIR Ioan PETEAN Ioan TĂUT la de

The mechanical alloying experiments were performed on a high
energy planetary ball mill. Four vials were used for powder mixtures milling.
The milling charge contains 46 steel balls having 15 mm average diameter and
100 g powder mixture. It corresponds to a charge level of ½ of the vial volume
and represents a 8:1 ball/powder ratio. The powder mixtures: Fe60Ni40, Fe50Ni50,
Fe40Ni60, were milled for 1, 2, 4, 8, 16, 32, 48 şi 64 hours. At each milling time
were taken samples for analysis (5 grams). The X-ray diffraction analysis
reveals that after 8 hours of milling the Fe peaks disappear and the Ni phase is
featured in all powder mass. The calculated crystal parameters prove that the
mechanical alloying process induces Ni structure for all powder mixtures after 8
hours of milling resulting a substitution solid solution where some Ni atoms
were replaced with Fe ones.
Cuvinte cheie: aliere mecanică, pulberi Fe Ni, moara planetară
Keywords: mechanical alloying, powder Fe Ni, planetary mill

34 ASPECTE STRUCTURALE ALE AMESTECURILOR