Thermodynamic behavior of Fe-Mn and Fe-Mn-Ag powder mixtures during selective laser melting

Kraner, Jakob (author), Medved, Jože (author), Godec, Matjaž (author), Paulin, Irena (author)

Additive manufacturing is a form of powder metallurgy, which means the properties of the initial metal powders (chemical composition, powder morphology and size) impact the final properties of the resulting parts. A complete characterization, including thermodynamic effects and the behavior of the metal powders at elevated temperatures, is crucial when planning the manufacturing process. The analysis of the Fe-Mn and Fe-Mn-Ag powder mixtures, made from pure elemental powders, shows a high susceptibility to sintering in the temperature interval from 700 to 1000 °C. Here, numerous changes to the manganese oxides and the αMn to βMn transformation occurred. The problems of mechanically mixed powders, when using selective laser melting, were highlighted by the low flowability, which led to a less controllable process, an uncontrolled arrangement of the powder and a large percentage of burnt manganese. All this was determined from the altered chemical compositions of the produced parts. The impact of the increased manganese content on the decreased probability of the transformation from γ-austenite to ε-martensite was confirmed. The ε-martensite in the microstructure increased the hardness of the material, but at the same time, its magnetic properties reduce the usefulness for medical applications. However, the produced parts had comparable elongations to human bone.

• Language: English
• Keywords: FeMn alloys, powder metallurgy, differential scanning calorimetry, selective laser melting, ε-martensite
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: NTF - Faculty of Natural Sciences and Engineering
• Publication status: Published
• Publication version: Version of Record
• Year: 2021
• Number of pages: 11 str.
• Numbering: Vol. 11, iss. 2, art. 234
• PID: 20.500.12556/RUL-134900
• UDC: 620.1/.2
• ISSN on article: 2075-4701
• DOI: 10.3390/met11020234
• COBISS.SI-ID: 49402627
• Publication date in RUL: 10.02.2022

Record is a part of a journal

• Title: Metals
• Shortened title: Metals
• Publisher: MDPI AG
• ISSN: 2075-4701
• COBISS.SI-ID: 15976214

Licences

• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.
• Licensing start date: 01.02.2021

Projects

• Funder: ARRS - Slovenian Research Agency
• Project number: J2-1729
• Name: Nova biorazgradljiva Fe-Mn zlitina izdelana s konvencionalnim postopkom in s postopkom dodajnih tehnologij s prilagojeno biorazgradljivostjo

• Funder: ARRS - Slovenian Research Agency
• Project number: P2-0132
• Name: Fizika in kemija površin kovinskih materialov