Method and device for measuring the power dissipated by a hydridation reaction in tubes and tubular claddings and the corresponding variation in electric resistance

Abstract

The invention relates to a method and device for measuring hydridation kinetics at different temperatures in tubular industrial components. The invention consists in measuring the power dissipated by a hydridation reaction over time as well as the variation in the electric resistance during said reaction. The inventive method and device can be used to optimise industrial components, such as tubes and fuel claddings for nuclear reactor cores. In this way, safety is increased, with the prevention of unplanned shutdowns of commercial reactors and a decrease in high-activity nuclear waste.

1 . Method for measuring hydridation kinetics, at different temperatures, in industrial components such as tubes and tubular claddings of metallic elements, metal alloys and any other material with and without protective coverings, wherein it consists of the measurement of: 
 a) the power dissipated by the hydridation reaction, hereinafter dissipated hydridation power, as a function of time, and of the dissipated hydridation energy, measured during the process, and    b) the variation in electric resistance during that reaction, and in particular during the stage of dissolution of hydrogen in the component preceding the precipitation of hydrides in the material.    the stages making up this method being:    i) insertion of the tubular component in a high or ultra-high vacuum chamber,    ii) circulation of hydrogen or a mixture of hydrogen with other gas(es) through the interior of the component, it being the permeation of the hydrogen via the wall of the component that causes the hydridation of the material,    iii) heating of the component by the Joule effect,    iv) determination of the power dissipated by the hydridation reaction as a function of time, of the dissipated hydridation energy measured during the process, and of the electric resistance in the component by means of: 
 iv.1) the voltage drop along the component, and  
 iv.2) the variation in electric current applied for maintaining its temperature at the predetermined value for the hydridation reaction.  
   
   
   
       2 . Device for carrying out the measurement method of hydridation kinetics at different temperatures, in industrial components such as tubes and tubular claddings of metallic elements, metal alloys and any other material with and without protective coverings, wherein it comprises the following elements: 
 a) a high or ultra-high vacuum chamber in which the component to be analysed is inserted,    b) a gas line for causing hydrogen or a mixture of hydrogen with other gas(es) to pass through the interior of the component,    c) heating systems by the Joule effect, thermocouples and systems for temperature control in the component, and    d) two electrodes in the form of a ring or other well-defined geometry, arranged symmetrically and equidistant from the central thermocouple.    
   
   
       3 . The method according to  claim 1 , wherein the measurements of hydridation kinetics are made in industrial components of metallic elements, metal alloys and any other material with and without protective coverings.  
   
   
       4 . The method according to  claim 3 , wherein the industrial components are tubular, among others, the tubes and tubular claddings for fuel in the cores of nuclear reactors.  
   
   
       5 . The device according to  claim 2 , wherein the measurements of hydridation kinetics are made in industrial components of metallic elements, metal alloys and any other material with and without protective coverings.  
   
   
       6 . The device according to  claim 5 , wherein the industrial components are tubular, among others, the tubes and tubular claddings for fuel in the cores of nuclear reactors