Microchannel heat exchangers for future electronics, air conditioning systems and heat pipes must provide an extremely high heat flux. Conventional heat transfer enhancement methods may not be applicable due to the small size of these heat exchangers. The present investigation is directed to solve problems of an effective cooling at high heat flux in microchannels and CHF increasing with help of an artificial nanorelief of the surface. The relief is formed by alumina nanoparticles which are deposited on the heating surface of the channel.