Hi,
There is a bit more to hard drilling than just carbide drill run slow. As a machinist, I do hard machining more than I want to sometimes.
First, you will need a rigid setup. Hand drills are worthless, cheap drill presses almost so. The drill needs to have good power. Your work needs to be clamped down firmly so it can't move. While drilling hard can be done dry, flood coolant is to be preferred. Don't use oils, it won't carry heat away fast enough. Use water soluble/based coolants.
Be careful of your speed and feed rate. Too slow rpm's can be as bad as too fast. Feed rates need to be fast enough to cut well without breaking down the cutting edge. Yet too light a feed rate causes rubbing and excess heat also ruining the cutting edge. Everything needs to be "balanced".
dalee