Senju Metal Industry Co., Ltd.

Tomoki Sasaki

Yoshie Tachibana

Shunsaku Yoshikawa

Shunsuke Koga

Yoshihiro Yamaguchi

Shinji Kikuchi

Norikazu Sakai

Ayumi Mio

A solder paste containing a first metal powder, a second metal powder, and a flux is employed. The first metal powder contains Sn. A second metal powderA has a core portionformed of an alloy containing Ni and Fe, and a surface layerthat covers the core portionand is formed of a metal containing Ni. An Ni content in the metal forming the surface layerof the second metal powderA is 50% by mass or more relative to a total mass of the metal forming the surface layerof the second metal powderA. The surface layerof the second metal powderA has a thickness of 0.05 μm or more and 0.30 μm or less.

Solder paste and solder joint

Provided are a solder alloy, a solder powder, a solder paste, and a solder joint having a low liquidus temperature and not too low solidus temperature. The solder alloy has an alloy composition of, by mass: Ag: 2.0 to 4.0%; Cu: 0.51 to 0.79%; and Bi: more than 4.0% and 8.0% or less, with the balance being Sn. The solder alloy has a liquidus temperature of less than 217° C.

Solder alloy, solder powder, solder paste and solder joint

Provided is a preform solder including a first metal containing Sn and a second metal formed of an alloy containing Ni and Fe. Alternatively, provided is a preform solder () having a metal structure including a first phase () that is a continuous phase and a second phase () dispersed in the first phase (), the first phase () contains Sn, the second phase () is formed of an alloy containing Ni and Fe, and a grain boundary () of a metal is present in the first phase ().

Preform solder and method of manufacturing the same, and method of manufacturing solder joint

Growing community of inventors

Tokyo, Japan

Tomoki Sasaki