Superheating metal alloy above solidus Is it possible to heat a material above its solidus without melting occurring?

More specifically, at a heating rate of approximately 200K/s, will a metal alloy exhibit superheating and if so by what order of magnitude i.e. fractions of a degree versus tens of degrees. What is the mechanism behind this?

There is a lot of information about supercooling but I am not certain whether this applies!
Yes, superheating can happen in some alloys. Whether it occurs at all, and its extent if it occurs, is very specific to each alloy (and heating rate dependent, obviously). It also depends on things like sample geometry (particles, solid, etc.) and size. This paper reports delays in melting by up to 100 K for some Al-Pb and Cu-Pb alloys.