And they celebrated by beating Australian top seeds, Louise Bawden and Taliqua Clancy, in three incredible sets.
In the men’s event Australian top seeds Chris McHugh and Bo Soderberg proved too strong for New Zealand’s Mike Watson and Sam O’Dea, winning in straight sets.
Artacho del Solar and Palmer won the opening set, 21-16, but then Bawden and Clancy stepped up to win the second set 21-6.
When the top seeds raced out to a 4-0 lead in the third the match looked over.
But the second seeds fought back, saved a match point and eventually won 17-15.
“That was pretty epic, that got about as close as it could go in the third set,” Palmer said.
Artacho del Solar said they had to dig deep after a poor second set.
“We just said let’s leave that behind us,” she said.
“We said it’s one set all, lets just go back to doing what we did in the first set, which was stay calm.”
For Palmer it was the second consecutive tour title, after winning on the Gold Coast with Manly’s Katie Bartoli.
That was also a one-tournament partnership, with Palmer and Bartoli beating Artacho del Solar and her regular partner, Nicole Laird, for the gold.
In the men’s final, New Zealanders Mike Watson and Sam O’Dea were aiming to win back-to-back tournaments after their impressive win at the Gold Coast in January.
But Soderberg and McHugh, a new pairing for this summer, were at the top of their game in the windy Perth conditions, winning in straight sets.
McHugh will now re-connect with regular partner, Isaac Kapa, who spent the summer recovering from a should operation, for the 2015 world tour and World Championships.
Watson and O’Dea have also qualified for the World Championships.