Soldering alloy, cream solder and soldering method
Patent 5918795 Issued on July 6, 1999. Estimated Expiration Date: 
January 31, 2017. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
January 31, 2017. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent References 16784 Lead-free, high temperature, tin based multi-component solder Lead-free solder alloys Composite solders Lead-free, tin-based multi-component solder alloys Patent #: 5730932 InventorsAssigneeApplicationNo. 792128 filed on 01/31/1997US Classes:228/200, Cooling under particular conditions420/561, Antimony, or bismuth containing420/562Antimony, or bismuth containingExaminersPrimary: Ryan, PatrickAssistant: Knapp, Jeffrey T. Attorney, Agent or FirmInternational ClassesB23K 035/26B23K 001/00 Foreign Application Priority Data1996-02-09 JPAbstractThe present invention relates to a soldering alloy composed mainly of Sn and free from lead which is a toxic substance. An addition of a small quantity of Ag to the soldering alloy can fine the alloy structure, minimize structural changes of the alloy and increase thermal fatigue resistance thereof. An addition of a small quantity of Bi to the soldering alloy lowers the melting point and improves the wettability thereof. Further, an addition of a small quantity of Cu restrains the growth of intermetallic compounds in the bonding interface between a copper land and the solder. Furthermore, an addition of a small quantity of In improves the elongation property and thermal fatigue resistance of the alloy. | |
