how come adhesive bond much better to aluminium then other metals?

Answer 1

I don't know that it does in general.

It may be that the Al was easier to abrade, and give a greater surface area...say compared w/ a hard stainless steel.

Abrading the surface (then cleaning w/ alcohol) is standard protocol for applying adhesives to metals and plastics.

Answer 2

that is a toss-up between JB Weld and chilly Weld through Permatex. both are 2 section epoxies which will properly be drilled, sanded, machined, painted, and immersed in water. i'm a touch more effective a fan of JB Weld. it variety of feels to be an exceptional bond. (Bonds iron, metal,aluminum,brass, bronze, copper, pewter, timber ceramics, plastic). oh, you likely received't locate those in hardware shops - pick to bypass to an motor vehicle provide homestead (telephone e book)