adamantium was not bonded to wolverine in a liquid form. the weapon x base had a nuclear reactor. through Kenji Oyama (Lord Darkwind's) process, resoirvors of adamantium were kept super-heated in a near plasma form at which point the adamantium was molecularly bonded to his bones, hence why the bones are "bonded, not "plated" and why wolverine can still produce red blood cells. don't believe everything the movie says. adamantium can still be melted by extremely intense heat, cyclops' optic blast at full force can atomize adamantium for example.