don't know - sounds like someone's PhD thesis.... Is it depend upon  
mismatch stress concentration orientation?  never see vertical  
mismatch (pure), even with gull wing.... Is it statement backed up  
with finite element modeling?  If it is, the modeler usually has  
their own language ;-).
IMHO.
jk
On Jan 9, 2020, at 8:50 PM, Bev Christian wrote:

> TechNetters,
>
>
>
> Can someone interpret this sentence for me?
>
> "As Sn is anisotropic, the size and orientation of the grain structure
> contributes to CTE mismatch fractures along the larger axis of a  
> solder
> joint, laterally rather than vertically."
>
>
>
> I know the following:
>
> 1.	Sn is anisotropic
> 2.	the size and orientation of the grain structure contributes to CTE
> mismatch fractures
>
> Is the latter part (.along the larger axis of a solder joint,  
> laterally
> rather than vertically.) always true and if so, why?  What am I  
> missing?
>
>
>
> Regards,
>
> Bev