hi !
I need to drill 1.0 inch in a piece of metal that has been fusionated:
mildsteel 1.4 inch and 0.25 inch of titanium (titanium clading ), the fusion between both resulted as very thin but hard to work and we think that is dammaging the inserts
( new inserts can hold maybe about three holes and at the end the corners brake )

this is what we use:

material SA 516 70 W- TITANIUM CLAD
coromill drill 1.0
COROKEY inserts 880 05 03 W08H P LM 4024