1. Processing aluminium EN AW 7075 alloy using selective laser meltingNejc Velikajne, Jože Medved, Matjaž Godec, Irena Paulin, complete scientific database of research data Abstract: Selective laser melting (SLM) is an additive manufacturing process, forming the desired geometry by selective layer fusion of powder material. Unlike conventional manufacturing processes, highly complex parts can be designed and manufactured with high accuracy and little post processing. Currently, different types of steel, aluminium, titanium and nickel-based alloys have been successfully processed; however, high strength aluminium alloy EN AW 7075 has not been processed with satisfying quality. The main focus of the investigation is to develop a new alloy which is more suitable for the SLM process for the wide used aluminium alloy EN AW 7075. But before that, gas-atomized powder material was characterized in terms of statistical distribution. A wide range of process parameters and different pre-heating temperatures were selected to optimize the process in terms of optimum volume density and reducing the effect of hot cracking. However, all laser-melted parts exhibited hot cracks which typically appear in aluminium alloy EN AW 7075. Keywords: EN AW 7075, aluminium alloy, hot cracks, relative density, selective laser melting (SLM) Published in DiRROS: 22.04.2024; Views: 48; Downloads: 0 |
2. Effect of steel’s thermal condition on the transformation temperatures of two hot-work tool steels with increased thermal conductivity : Tilen Balaško, Jaka Burja, Jožef MedvedTilen Balaško, Jaka Burja, Jože Medved, 2023, original scientific article Keywords: thermal analysis, hot-work tool steels, differential scanning calorimetry, heat treatment Published in DiRROS: 08.03.2024; Views: 85; Downloads: 46 Full text (3,08 MB) This document has many files! More... |
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4. Aspects of bending high-borated austenitic stainless steel sheets for interim storage of spent nuclear fuelJosef Odehnal, Tomáš Studecký, Petra Čejková, Ivana Poláková, Martin Rund, Václav Bruná, Petr Martinek, Pavel Francisko, Črtomir Donik, 2023, original scientific article Keywords: interim storage, spent fuel, borated stainless steel, cold working, bending Published in DiRROS: 01.02.2024; Views: 139; Downloads: 64 Full text (10,05 MB) This document has many files! More... |
5. Predicting the quality of grain refiners from electrical resistance measurements of aluminumMaja Vončina, Irena Paulin, Jože Medved, Mitja Petrič, 2023, original scientific article Keywords: Al-Ti-B grain-refiners, quality, TiB2 particles, Al3Ti particles, electrical resistance measurements Published in DiRROS: 01.02.2024; Views: 169; Downloads: 72 Full text (8,93 MB) This document has many files! More... |
6. Comparison of cycling high temperature corrosion at 650°C in the presence of NaCl of various austenitic stainless steelsMirjam Bajt Leban, Maja Vončina, Tadeja Kosec, Robert Tisu, Matevž Barborič, Jože Medved, 2023, original scientific article Abstract: The high temperature corrosion at 650°C in the presence of NaCl at atmospheric pressure of AISI 304L, AISI 309, AISI 310S, AISI 314 and AISI 321 austenitic stainless steel was studied. The specimens were cyclically heated in the furnace and immersed in a 3.5% aqueous NaCl solution after cooling for 15 min. After each cycle, the change in mass of the samples was measured. The corroded samples were analysed by SEM /EDX, and the corrosion products were analysed by XRD. The chloride ions react with the steel surface to form porous and poorly adherent oxides and metal chlorides. After the mass increase during the first exposure cycles, spalling of the oxides occurred. The high temperature austenitic stainless steels (AISI 309, AISI 310S, AISI 314) showed less mass loss than conventional austenitic steels (AISI 304L). Surprisingly, the stainless steel AISI 321 showed a similar low weight loss after the cyclic test as AISI 309, but a detailed analysis of the exposed surfaces after the test showed a similar corrosion attack as for AISI 304. After the cyclic test at high temperature in the presence of NaCl, a higher concentration of Cr and Ni definitely improves the corrosion resistance under the present conditions, but a certain addition of Si is even more obvious. Keywords: austenitic stainless steel, high temperature corrosion, NaCl, exhaust systems, open access Published in DiRROS: 31.05.2023; Views: 264; Downloads: 172 Full text (1,53 MB) This document has many files! More... |
7. First report of Erysiphe corylacearum on Corylus avellana and C. colurna in SloveniaJanja Zajc, Mojca Rot, David Snoj, Metka Žerjav, Hans-Josef Schroers, Barbara Piškur, Nikica Ogris, Ana Brglez, 2023, short scientific article Keywords: common hazel, Turkish hazel, powdery mildew Published in DiRROS: 28.02.2023; Views: 520; Downloads: 198 Full text (258,92 KB) This document has many files! More... |
8. Diversity, migration routes, and worldwide population genetic structure of Lecanosticta acicola, the causal agent of brown spot needle blightMarili Laas, Kalev Adamson, Irene Barnes, Josef Janoušek, Martin S. Mullett, Katarína Adamčíková, Mitsuteru Akiba, Ludwig Beenken, Helena Bragança, Timur S. Bulgakov, Barbara Piškur, 2022, original scientific article Abstract: Lecanosticta acicola is a pine needle pathogen causing brown spot needle blight that results in premature needle shedding with considerable damage described in North America, Europe, and Asia. Microsatellite and mating type markers were used to study the population genetics, migration history, and reproduction mode of the pathogen, based on a collection of 650 isolates from 27 countries and 26 hosts across the range of L. acicola. The presence of L. acicola in Georgia was confirmed in this study. Migration analyses indicate there have been several introduction events from North America into Europe. However, some of the source populations still appear to remain unknown. The populations in Croatia and western Asia appear to originate from genetically similar populations in North America. Intercontinental movement of the pathogen was reflected in an identical haplotype occurring on two continents, in North America (Canada) and Europe (Germany). Several shared haplotypes between European populations further suggests more local pathogen movement between countries. Moreover, migration analyses indicate that the populations in northern Europe originate from more established populations in central Europe. Overall, the highest genetic diversity was observed in south-eastern USA. In Europe, the highest diversity was observed in France, where the presence of both known pathogen lineages was recorded. Less than half of the observed populations contained mating types in equal proportions. Although there is evidence of some sexual reproduction taking place, the pathogen spreads predominantly asexually and through anthropogenic activity. Keywords: brown spot needle blight, Lecanosticta acicola, pones, Pinus spp., popularion structure Published in DiRROS: 12.08.2022; Views: 570; Downloads: 282 Full text (3,06 MB) This document has many files! More... |
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10. Genetic aspects linked to production and use of forest reproductive material (FRM) : collecting scientific evidence for developing guidelines and decision support tools for effective FRM managementDušan Gömöry, Katri Himanen, Mari Mette Tollefsrud, Claes Uggla, Hojka Kraigher, Sandor Bordacs, Paraskevi Alizoti, Stuart A'Hara, Aline Frank, Gunnar Friis Proschowsky, Josef Frýdl, Thomas Geburek, Monique Guibert, Mladen Ivanković, Ana Jurše, Stuart Kennedy, Jan Kowalczyk, Heike Liesebach, Tiit Maaten, Andrej Pilipović, Roberta Proietti, Volker Schneck, Alain Servais, Brynjar Skúlason, Christoph Sperisen, Frank Wolter, Tefide Yüksel, Michele Bozzano, 2021, dictionary, encyclopaedia, lexicon, manual, atlas, map Abstract: This report summarises the current state of knowledge in genetic aspects linked to the production and use of forest reproductive material (FRM). The first chapter describes the different categories of FRM, considers the strategic choice between artificial and natural regeneration in the face of climate change, and articulates the need for and purposes of FRM. Chapter 2 outlines the FRM production chain, in terms of: i) FRM approval, management, collection and certification (seed sources, stands, orchards, plus trees and clones others); ii) Testing standards and examples; iii) Effect of seed and seedling material not intended for use as FRM on forest genetic resources; iv) Breeding effects on basic material including conservation strategy; v) Harvesting, processing and storage of seeds; vi) Nursery practices; vii) Certification and Traceability; and viii) FRM Trading and Transport. Chapter 3 examines FRM with regard to: i) Forest regeneration strategies % especially considering climate change, and ii) Assisted migration and available decision support tools. Chapter 4 provides a detailed overview of forest establishment methods, and chapter 5 looks at keeping records of seed origin to improve forest management. The final chapter offers 38 recommendations arising from the review. This work is the result of an international collaboration rooted in EUFORGEN for more than two decades. It is built on the firm belief that the genetic element is decisive for the creation of a resilient forest capable of surviving threats and adapting to changes, thus enabling the evolution of ecosystems and the conservation of the productive landscape. Keywords: forest reproductive material Published in DiRROS: 05.11.2021; Views: 827; Downloads: 460 Full text (5,81 MB) This document has many files! More... |