A. García-Junceda

Bio: A. García-Junceda is an academic researcher from IMDEA. The author has contributed to research in topics: Microstructure & Spark plasma sintering. The author has an hindex of 14, co-authored 37 publications receiving 690 citations. Previous affiliations of A. García-Junceda include Spanish National Research Council & Complutense University of Madrid.

High-entropy alloys fabricated via powder metallurgy. A critical review

Abstract: High-entropy alloys (HEAs) have attracted a great deal of interest over the last 14 years. One reason for this level of interest is related to these alloys breaking the alloying principles ...

Evolution of Microstructural Banding during the Manufacturing Process of Dual Phase Steels

Abstract: The segregation of manganese during solidification from casting is responsible for banding problems of dual phase steels. Microstructural banding lasts during all the manufacture process, producing the deterioration of the material, so the final ductility and impact toughness of the sheets are decreased due to the high level of anisotropy. To avoid or reduce the problem of microstructural banding, it is proposed to modify the hot rolling parameters so the formation of ferrite-pearlite microstructures is avoided and thus the presence of banding. The study of the microstructural evolution during the whole manufacturing process reveals that the increase of the cooling rate during the hot rolling leads to a significant decrease of martensite banding in the microstructure of dual phase steels for sheets used in the automotive industry.

Influence of the microstructure on the tensile and impact properties of a 14Cr ODS steel bar

Abstract: A Fe–14Cr–1W–0.4Ti–0.3Y203 ferritic steel bar was characterised by different microstructural techniques in order to evaluate the link between its microstructure and the mechanical properties achieved. This bar was produced by mechanical alloying of a pre-alloyed gas atomised powder with yttria particles, followed by hot extrusion and subsequently annealing. The knowledge of the microstructure of this 14Cr oxide dispersion strengthened (ODS) steel allows for the explanation of the mechanical properties observed, such as the decrease of the ductility found in the transverse orientation of the bar, the existence of zig-zag crack paths in the broken specimens after the impact tests at low temperatures and the appearance of delaminations when the temperature is increased.

Recent developments in stainless steels

Abstract: This article presents an overview of the developments in stainless steels made since the 1990s. Some of the new applications that involve the use of stainless steel are also introduced. A brief introduction to the various classes of stainless steels, their precipitate phases and the status quo of their production around the globe is given first. The advances in a variety of subject areas that have been made recently will then be presented. These recent advances include (1) new findings on the various precipitate phases (the new J phase, new orientation relationships, new phase diagram for the Fe–Cr system, etc.); (2) new suggestions for the prevention/mitigation of the different problems and new methods for their detection/measurement and (3) new techniques for surface/bulk property enhancement (such as laser shot peening, grain boundary engineering and grain refinement). Recent developments in topics like phase prediction, stacking fault energy, superplasticity, metadynamic recrystallisation and the calculation of mechanical properties are introduced, too. In the end of this article, several new applications that involve the use of stainless steels are presented. Some of these are the use of austenitic stainless steels for signature authentication (magnetic recording), the utilisation of the cryogenic magnetic transition of the sigma phase for hot spot detection (the Sigmaplugs), the new Pt-enhanced radiopaque stainless steel (PERSS) coronary stents and stainless steel stents that may be used for magnetic drug targeting. Besides recent developments in conventional stainless steels, those in the high-nitrogen, low-Ni (or Ni-free) varieties are also introduced. These recent developments include new methods for attaining very high nitrogen contents, new guidelines for alloy design, the merits/demerits associated with high nitrogen contents, etc.

Machine learning in additive manufacturing: State-of-the-art and perspectives

Abstract: Additive manufacturing (AM) has emerged as a disruptive digital manufacturing technology. However, its broad adoption in industry is still hindered by high entry barriers of design for additive manufacturing (DfAM), limited materials library, various processing defects, and inconsistent product quality. In recent years, machine learning (ML) has gained increasing attention in AM due to its unprecedented performance in data tasks such as classification, regression and clustering. This article provides a comprehensive review on the state-of-the-art of ML applications in a variety of AM domains. In the DfAM, ML can be leveraged to output new high-performance metamaterials and optimized topological designs. In AM processing, contemporary ML algorithms can help to optimize process parameters, and conduct examination of powder spreading and in-process defect monitoring. On the production of AM, ML is able to assist practitioners in pre-manufacturing planning, and product quality assessment and control. Moreover, there has been an increasing concern about data security in AM as data breaches could occur with the aid of ML techniques. Lastly, it concludes with a section summarizing the main findings from the literature and providing perspectives on some selected interesting applications of ML in research and development of AM.