To burn the pre-alloyed Ti in O, liquid metal is hot, making the injector difficult.
Maybe an alternative would be to burn solid pre-alloyed Ti, in a thermal lancehttps://en.wikipedia.org/wiki/Thermal_lance
that is, make a tube and optionally wires of the Ti alloy, blow oxygen through it, light the end.
The fineness of the alloyed TiO2
powder is more difficult to control: through oxygen speed, turbulence, wall and wires thickness...
If lighting the tube with a spark from a car battery, please be careful. Seriously.
Since Zr and Hf are difficult to separate, using both simultaneously to alloy Ti must be cheaper.