The Teledyne Titan (all-titanium) was out in 1973 or sooner.
Graphite tubing, graphite reinforced aluminum tubing and other composite frame, usually bonded or "glued ans screwed" into aluminum lugs was available in the very early 70's , as well.
Klein composite bikes were available in the mid 70's. Klein welded aluminum (with composite reinforcements?) bikes were available in about 1980.
The ALAN, all aluminum, "glued and screwed" together, were available in about 1972.