	US 11,858,071 B2
	Solder alloy, solder paste, solder ball, solder preform, and solder joint
Yoshie Tachibana, Tokyo (JP); and Ryuki Horie, Tokyo (JP)
Assigned to Senju Metal Industry Co., Ltd., Tokyo (JP)
Filed by Senju Metal Industry Co., Ltd., Tokyo (JP)
Filed on Oct. 21, 2022, as Appl. No. 17/971,064.
Claims priority of application No. 2021-172858 (JP), filed on Oct. 22, 2021.
Prior Publication US 2023/0127584 A1, Apr. 27, 2023
Int. Cl. B23K 35/26 (2006.01); C22C 13/02 (2006.01)

CPC B23K 35/262 (2013.01) [C22C 13/02 (2013.01)]

5 Claims

1. A solder alloy having an alloy composition consisting of, by mass %:

Ag: 2.5 to 3.7%,

Cu: 0.25 to 0.95%,

Bi: 3.0 to 3.9%, and

In: 0.5 to 2.3%, with the balance being Sn,

wherein the alloy composition satisfies the following relations (1) to (3):

8.1≤Ag+2Cu+Bi+In ≤11.5 Relation (1)

1.30≤(Bi+In)/Ag≤1.66 Relation (2)

4.48≤Ag×Cu×Bi×In≤7.7 Relation (3)

wherein Ag, Cu, Bi, and In in the relations (1) to (3) each represent the contents (mass %) thereof in the alloy composition.