Synthesis and characterization of Nb3Sn intermetallic compound by mechanical alloying and heat treatment

Toghyani Mornani, Maryam; Nozad, Ahmad; Asadi Asadabad, Mohsen

Synthesis and characterization of Nb3Sn intermetallic compound by mechanical alloying and heat treatment

Document Type : Research Paper

Authors

Maryam Toghyani Mornani

Ahmad Nozad

Mohsen Asadi Asadabad

Abstract

Nb₃Sn superconductor compound is the most widely used material for generating magnetic fields above 10T. But, this intermetallic compound is obtained by thermal reactions at high temperatures (>2000°C). Therefore, in recent years the researchers have investigated the processes that permit the formation of the Nb₃Sn superconducting phases at lower temperatures (<1000°C). The aim of this study was preparation of nanocrystalline Nb₃Sn intermetallic compound using mechanical alloying and heat treatment at low temperature. The phase transitions of milled powder before and after the heat treatment were characterized using X-ray diffractometry (XRD). The microstructural analyses were performed using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The grain size and lattice strain were calculated using the Williamson-hall method. During the milling, mechanical alloying of Nb-Sn elemental powders resulted in the formation of a solid solution, while the heat-treatment led to the formation of Nb₃Sn phase. The results showed that Nb₃Sn XRD peaks appeared after the heat treatment at 600°C for the powder milled for 10h.

Keywords

Nb3 Sn intermetallic compound

Mechanical alloying

Heat treatment

Nanostructural materials

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