My info about the main tubes come from the sticker attached to my former 86 Technium 440 and Raleigh USA's brochure. The frame sticker looked like this one off an 88 model.
I believe I have a similar sticker on my unknown-year Technium Pro.
Did they make ongoing manufacturing changes through the Technium product cycle? Could the 6013 tubes be spec for their Mtb's?
My reference was specifically to the OP's bicycle, which uses 6013 main tubes, as did all three of the 1986, 1st generation models. Raleigh did switch to 6061 for the 1987models, so it's always possible that the change happened sometime during the 1986 model year, but the original production runs were 6013. Over the years, Raleigh would use the Technium bonding process on several materials. Offhand, I recall Easton (E9?), Reynolds 531 and Reynolds 753.