APPARATUS FOR DETERMINING PHASE TRANSITIONS BY MEANS OF A SAMPLE TAKEN FROM A METAL MELT

摘要

Device for determining phase transitions by thermal analysis using a sample taken from a liquid metal, which comprises a consumable measuring probe having a solidification chamber into which the melt flows. The solidification chamber contains a temperature sensor for recording the course of the cooling over a specified period of time. According to the invention, the side wall of the solidification chamber (3) comprises a metal jacket (4) which encloses the chamber completely and which extends in the longitudinal direction of the measuring probe (1). The two open ends of the jacket (4) are covered with plugs (5, 6) made of a material whose thermal conductivity is substantially less than that of the material of which the jacket is made. The jacket is completely enclosed by a cladding (2, 8) which is made of a material whose thermal conductivity is substantially less than that of the jacket metal. The inlet opening for the melt comprises a quartz tube (9) enclosed by a metal tube (10). According to the invention, the mass of the jacket (4), which is given by its height (h) and its wall thickness (b), is such that the heat given off by the melt flowing into the solidification chamber and taken up by the metal jacket results in an equilibrium temperature in the vicinity of the temperature sensor which is as near as possible to the solidification temperature.