HEAT EXCHANGER AND MANUFACTURING METHOD OF THE SAME

PROBLEM TO BE SOLVED: To provide a heat exchanger capable of improving brazing properties without causing deterioration of productivity.SOLUTION: A heat exchanger for cooling a first fluid by performing heat exchange between the first fluid, which is a gas, and a second fluid, which is a liquid whose temperature is lower than that of the first fluid, includes: a core part 3 in which the second fluid circulates inside and in which an outer part is constituted by laminating a plurality of tubes 1 in which the first fluid circulates and fins 2; a core plate 4a which is connected to at least one end part of the plurality of tubes 1; and a first fluid flow passage forming member 5 which is arranged so as to cover the core part 3 and the core plate 4a and which forms a first fluid flow passage in which the first fluid circulates. Between the tubes 1 and the fins 2, between the tubes 1 and the core plate 4a and between the core plate 4a and the first fluid flow passage forming member 5 are bonded by brazing respectively, and Si content of a brazing filler metal coated on the core plate 4a is 11.3% or greater.SELECTED DRAWING: Figure 5 【課題】生産性の悪化を招くことなく、ろう付け性を向上させることが可能な熱交換器を提供する。【解決手段】気体である第１流体と第１流体より低温の液体である第２流体との間で熱交換を行うことで、第１流体を冷却する熱交換器において、内部を第２流体が流通するとともに、外部を第１流体が流通する複数のチューブ１およびフィン２を積層して構成されたコア部３と、複数のチューブ１の少なくとも一方の端部に接続されるコアプレート４ａと、コア部３およびコアプレート４ａを覆うように配置されるとともに、第１流体が流通する第１流体流路を形成する第１流体流路形成部材５とを設ける。チューブ１とフィン２の間、チューブ１とコアプレート４ａの間、コアプレート４ａと第１流体流路形成部材５の間は、それぞれろう付けにより接合されており、コアプレート４ａに塗布されるろう材のＳｉ含有率を１１．３％以上とする。【選択図】図５