Abstract: A heat transfer tube having an inner surface provided with a dense pattern of polyhedrons having crack-like cavities on at least two surfaces of a single polyhedron, forming three-dimensional crack-like cavities that enhance flow evaporation heat transfer. The tube is made by (a) forming in an inner surface for the tube a plurality of generally parallel first grooves, (b) forming in the inner surface and over the first grooves a plurality of generally parallel second fins extending at a first angle of between 0 and about 25 degrees relative to a longitudinal axis for the tube to thereby devolve the second angle fins into the pattern of cavities, and (c) forming in the second fins a pattern of generally parallel crosshatches extending cross-wise thereto.