To provide a brazing heat treatment method which brings low product manufacturing cost and superior resistance against heat, corrosion and high temperature oxidation in a brazed joined part, and also to provide a brazed product having improved reliability in brazed joined parts.
In this brazing heat treatment method, a brazing material 10 having a brazing layer 15 on the surface of a base material 11 is heated in a high vacuum state for the brazing heat treatment. The brazing material 10 is arranged in a vacuum heating furnace together with Cr or a Cr alloy. Then, at a heat treatment temperature T in the range of 900≤T≤1,200°C, the brazing heat treatment is performed under conditions in which the degree of vacuum V satisfies an expression, V≤4×10{(T/100)-13}(Pa), with the brazing layer 15 fused, and with chromium components of Cr or a Cr alloy evaporated in the vacuum heating furnace. Subsequently, the vacuum heating furnace is cooled to vapor-deposit a Cr or Cr alloy layer on the surface of the brazing layer 15.
KURODA HIROMITSU
SAGAWA HIDEYUKI
SHIRAI SUKAKU
