Why Titanium? If you look online there are many projects from plasma speakers etc and they dont melt the metal, even copper can be used. What exactly have you in mind? Depending on what your doing you might be able to use copper for it.
If we knew more about what you are actually planning, we might be able to offer alternatives to try. For example, in TIG welding, tungsten electrodes are used. The actual welding plasma is quite a bit hotter than the melting point of tungsten, but the electrode doesn't melt, it just wears a bit (ignoring that there are ways to melt the electrode tip to make it rounded).
Plasma near that temperature is also present in the EDM process of machining. It is done with synthetic graphite or copper electrodes to remove and shape cavities in steel or other metals. But like the TIG welding John mentioned there is a slight amount of wear to the electrode.