1 Reply Latest reply on Aug 19, 2015 8:47 AM by Janko Stellaard

    Solder Creep

    Christian Rommelfanger

      I try to simulate creep in an electornic bga package under thermal cycling. The key to the right result will be the creep constants for the solder. All constants i found online are for the hyperbolic sine creep law. As far as I know solid works can only work with the Nortons creep law.

       

      Can i somehow implement the hyperbolic sine creep law?

      Is there any way to get the right creep constants for a common solder?

       

      Or can i possibly calculate the norton creep constants with the given hyperbolic sine constants?

        • Re: Solder Creep
          Janko Stellaard

          hi Christian,

           

          Maybe this is usefull: (the article is attached in PDF)

           

          S-018620

          Deriving creep constants from creep curve data:

          COSMOSWorks and COSMOSDesignSTAR use the Classical Power Law for Creep (Bailey-Norton law).

          The creep strain at time t is : (see pdf)

          where:

          T = Temperature (Kelvin) (= input temperature + reference temperature + offset temperature)

          CT = A material constant defining the creep temperature-dependency

          C0, C1 and C2 are the three creep constants

           

          The full article is available in pdf format, in the attachment tab of this Solution