Measurement of Curie or Neel temperature - for samples during manufacture of magnetic materials

摘要

The Curie or Neel temperature of ferromagnetic or ferrimagnetic materials is a characteristic of the composition of the material used during manufacture. Two vertical mounts (12, 14) on a base (10) support a horizontal plate (16) through which passes a moving shaft (22) with elasticated suspension (17). At the ends of the shaft are two sample carriers (30, 32). The upper carrier (30) is heated in a cylindrical electric furnace (34). The lower carrier (32) is cooled in a variable temperature crystat (40). A permanent magnet (42) provides horizontal lines of a magnetic field in the region of the particular sample being tested. Angular displacement created by the magnet is measured by a differential transformer (50) with a moving core (52). Electronic circuits control, program and process the tests.