Peter Cvahte

Dr. Peter Cvahte


Research Focus & Metrics

Academic Career Length

7Years (2020-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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14 April 2021 in Crystals
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SRSimon Rečnik
Simon Rečnik
MBMilan Bizjak
Milan Bizjak
Jožef MedvedJožef Medved
Jožef Medved
PCPeter Cvahte
Peter Cvahte
BKBlaž Karpe
Blaž Karpe
Aleš NagodeAleš Nagode
Aleš Nagode
In the present work, free-cutting aluminum alloy AA6026 with 1.1 wt.% bismuth addition was fabricated by different melt preparation methods in order to investigate whether the melt preparation route affects the solidification sequence and thus has an influence on the machinability of the alloy. All experiments were designed to simulate variable industrial conditions: addition of bismuth in an induction melting furnace, addition of bismuth in an electric resistance holding furnace, addition of bismuth together with grain refiner, effect of holding time and melt temperature before casting. Detailed thermodynamic analyses (DSC, Thermo-Calc) and microstructural characterization (SEM-EDS, XRD) have been performed to explain the solidification sequence, microstructure development and especially formation of the intermetallic Mg3Bi2 phase.

14 February 2024 in Metals
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BKBojan Kropf
Bojan Kropf
PCPeter Cvahte
Peter Cvahte
MAMatija Arzenšek
Matija Arzenšek
JKJakob Kraner
Jakob Kraner
The present study investigates the accumulative roll bonding process applied to the EN AW 3003 aluminum alloy, serving as a composite material on both sides and consisting of the EN AW 4343 aluminum alloy. For the characterization of the optical microscopy, corrosion tests with saltwater acetic acid and mechanical properties before and after the braze test were employed. The numerical simulations accurately predicted the industrial cold rolling values for the rolling force and surface temperature. The most comprehensive understanding of the cold rolling parameters for both side-cladded materials was achieved by combining predictions for cladded and uncladded materials. The thickness of the cladded layer presented as a percentage after roll bonding was 18.7%. During the cold rolling and annealing, the cladded thickness was increased to 24.7% of the final 0.3 mm of the total cold-rolled product thickness. According to the performed braze test for final thickness, the ultimate tensile strength and yield strength were decreased, and the elongation increased to 18.1%. In addition to the described changes in mechanical properties, the material’s anisotropy improved from 5.4% in the cold-rolled condition to 2.0% after the braze test. After multiple re-meltings of the cladded material, the analyzed chemical compositions allow for recycling and reuse as different 4xxx, 5xxx, and 6xxx alloys.

20 July 2023 in Metals
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JKJakob Kraner
Jakob Kraner
PCPeter Cvahte
Peter Cvahte
PŠPrimož Šuštarič
Primož Šuštarič
TŠTomaž Šuštar
Tomaž Šuštar
ČDČrtomir Donik
Črtomir Donik
KKKyung Il Kim
Kyung Il Kim
Hot rolling in the process chain of aluminum-rolled products presents the critical element of material quality and influences productivity. To increase the letter demand modifications of hot rolling, the consequential changes of microstructure, crystallographic texture, and mechanical and formability properties must be acknowledged and consistently considered when planning the rolling process and rolled product. Achieving lower thicknesses of the hot-rolled band would enable fewer passes with cold rolling; consequently, hot rolling with the same number of passes can be completed with lower temperatures. Microstructural and texture characterizations conducted using the light microscope and scanning electron microscope, respectively, of the 3.25 mm hot-rolled band revealed that the smaller grains appeared in the center of the cross-section, unlike for the 6 mm hot-rolled band, where smaller grains were detected on the top and bottom positions of the cross-section. Furthermore, the comparison also shows that the 6 mm hot-rolled band had 64% of random texture components and 83% of recrystallized grains, whereas the proportional adjustment for the 3.25 mm hot-rolled band had 42% of random texture components and 55% of recrystallized grains. For the mechanical testing results, the elongation values in rolling and transverse directions significantly differ only in the case of a hot-rolled band of 3.25 mm. Consequently, the earing results are more than 1.5% higher for the 3.25 mm hot-rolled band, than the 6 mm hot-rolled band.

20 June 2023 in Preprints.org
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JKJakob Kraner
Jakob Kraner
PCPeter Cvahte
Peter Cvahte
PŠPrimož Šuštarič
Primož Šuštarič
TŠTomaž Šuštar
Tomaž Šuštar
ČDČrtomir Donik
Črtomir Donik
KKKyung Il Kim
Kyung Il Kim
The hot rolling in the process chain of the aluminium rolled products present the critical element of material quality and influence on productivity. The desire to increase the letter demand modifications of hot rolling, consequential changes of microstructure, crystallographic texture, mechanical and formability properties must be knowledge and consistently considered in planning the rolling process and rolled product. Achieving lower thicknesses of the hot-rolled band would enable fewer passes with cold rolling; consequently, hot rolling with the same number of passes will complete with lower temperatures. Microstructural and texture characterization with the optical microscope and scanning electron microscope for the hot-rolled band 3.25 mm the smaller grains appeared in the center of the cross-section, unlike for the hot-rolled band 6 mm, the smaller grains were detected on the upper and bottom position of the cross-section. Furthermore, the comparison shows also that the hot-rolled band 6 mm has 64 % of random texture components and 83 % of recrystallized grains, and the proportional adjustment for the hot-rolled band 3.25 mm has the 42 % of random texture components and 55 % of recrystallized grains. For the mechanical testing results, the elongation values in rolling and transverse directions significantly differ just in the case of a hot rolled band of 3.25 mm. Consequently, the earing results are more than 1.5 % higher for the hot-rolled band, 3.25 mm, than the hot-rolled band, 6 mm.

29 January 2021 in Metals
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Journal Article
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Irena PaulinIrena Paulin
Irena Paulin
ČDČrtomir Donik
Črtomir Donik
PCPeter Cvahte
Peter Cvahte
MGMatjaž Godec
Matjaž Godec
The demand for aluminum alloys is increasing, as are the demands for higher strength, with the aim of using lighter products for a greener environment. To achieve high-strength, corrosion-resistant aluminum alloys, the melt is rapidly solidified using the melt-spinning technique to form ribbons, which are then plastically consolidated by extrusion at elevated temperature. Different chemical compositions, based on adding the transition-metal elements Mn and Fe, were employed to remain within the limits of the standard chemical composition of the AA5083 alloy. The samples were systematically studied using light microscopy, scanning electron, and transmission microscopy with electron diffraction spectrometry for the micro-chemical analyses. Tensile tests and Vickers microhardness were applied for mechanical analyses, and corrosion tests were performed in a comparison with the standard alloy. The tensile strength was improved by 65%, the yield strength by 45% and elongation by 14%. The mechanism by which we achieved the better mechanical and corrosion properties is explained.

6 November 2020 in Metals
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DBDavid Bombac
David Bombac
PCPeter Cvahte
Peter Cvahte
MBMartin Balog
Martin Balog
GKGoran Kugler
Goran Kugler
MTMilan Terčelj
Milan Terčelj
An industrial press was used to consolidate compacted aluminum powder with a nominal diameter in the range of 1 µm. Direct and indirect hot-extrusion processes were used, and suitable process parameters were determined from heating conditions, ram speeds and billet temperatures. For comparison, a direct-extrusion press for hot extrusion of a conventional aluminum alloy AA 1050 was used. The extruded Al powder showed better mechanical properties and showed a thermal stability of the mechanical properties after annealing treatments. To increase the theoretical density of the directly extruded Al powder, single-hit hot-compression tests were carried out. Activation energies for hot forming were calculated from hot-compression tests carried out in the temperature range 300–580 °C, at different strain rates. Processing maps were used to demonstrate safe hot-working conditions, to obtain an optimal microstructure after hot forming of extruded Al powder.