Not sure what you mean by open a new form, but I will take a wild stab and say this functionality does not exist in AX, unless you mean CTRL+N.
I am throwing example.
In navision we have the sales order , in that sales order header we have a field sell - to customer no . if i press the F6 in that filed then it will open the customer list . ( table relation concept) . simply it will open another form of customer list.
then what about the in Axapta . ( i know the concept of GO - To main table Form ) excep t this is there any short cut .