摘要 |
PROBLEM TO BE SOLVED: To stabilize the amt. of hydrogen contained in the object to be treated and to uniformize its magnetic properties by measuring the temp. of an alloy in a hydrogen discharging and recombination reaction stage and detecting the end point of the reaction in HDDR treatment on the basis of the temp. SOLUTION: Since the temp. of the objet to be treated (alloy) in the case of hydrogen discharging and recombination reaction drops by the heat of reaction in accordance with the hydrogen discharging reaction, the drop in the temp. of the alloy exhibits the progression of this reaction. That is, the temp. of the alloy drops accordance with the heat absorption in the hydrogen discharge, but, at the end of the hydrogen discharging reaction, the temp. of the alloy rapidly increases and approaches the temp. in a furnace. Therefore, by measuring the temp. of the alloy, the end point of the hydrogen discharging reaction can easily be decided. More concretely, it is judged that the hydrogen discharging reaction is finished at the point of time in which the temp. of the alloy is increased up to the level at which the value obtd. by subtracting the temp. of the alloy from the temp. in the furnace reaches <=10 deg.C. |