I am seriously thinking to replace my 25-year-old cedar decking with aluminium planks. Is there any hidden fastener I can use to mount bleacher planks to the wood frame? These are the same planks used in stadium seating. You can google it to see what it looks like.

Just for your reference, most aluminium decks are about $10/sf. My local lumber store has cedar for $4/sf. But I know alumumium extrusion companies sell aluminium bleacher plank for about $6 /sf. They also make aluminium interlocking boat dock flooring. By the way, one aluminium deck company sells the same flooring with 50% markup...