Study of the hydrogen and nitrogen absorption processes by alloys of the Mn-Fe-Sn ternary system

• Grant number: 14/14354-1
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: October 01, 2014
• End date: October 31, 2017
• Field of knowledge: Physical Sciences and Mathematics - Physics - Condensed Matter Physics
• Principal Investigator: Sergio Gama
• Grantee: Karen Midori Ono
• Host Institution: Instituto de Ciências Ambientais, Químicas e Farmacêuticas (ICAQF). Universidade Federal de São Paulo (UNIFESP). Campus Diadema. Diadema , SP, Brazil

Abstract

Magnetic materials are important in several technological areas. Two research areas are in development in actuality. The first is magnetic refrigeration, which can replace the conventional gas compression technology for the reasons of better efficiency and no emission of gases that affect the ozone layer. The second area is the one of thermomagnetic devices, mainly motors, which are able of convert thermal energy into mechanical and electrical energy in a sustainable way. For these two new developing technologies it is necessary to have magnetic materials whose. Curie temperatures can be tuned by a parameter like the composition. It has been already determined that variation of the Fe concentration in the compounds (Mn3-xFex)Sn and (Mn2-xFex)Sn results in considerable variation of their Curie temperatures. It is also well known that intermetallic compounds that absorb hydrogen or nitrogen change appreciably their saturation magnetization and their Curie temperatures. In this work it is proposed to choose one composition of each of these two compounds of the Mn-Fe-Sn system, and study how the absorption of hydrogen and nitrogen affect their structural and magnetic properties. We aim to obtain cheap and abundant materials with convenient structural and magnetic properties to be applied in magnetic refrigerators and thermomagnetic motors.