Nope!
Most U.S. coin collectors know that the United States Mint continued to pump 1964-dated 90% silver dimes, quarters and half dollars into circulation through 1965 and into early 1966. The reasons for doing this were several, some of them quite reasonable at the time.
Source here
It takes a bit of searching to find this. It looks like it's being memory-holed.
64 was the last year the were officially minted, except for 40% and proofs, which you can still buy.