Abstract: A nozzle for continuous casting which is capable of uniformly supplying a required amount of gas to the inner wall surface thereof by providing a plurality of communication holes inside the nozzle body between the inner surface thereof and a gas pressure balance chamber disposed inside the nozzle body so as to communicate the chamber with the inner surface, the communication hole having a square measure corresponding to that of a circular hole having a diameter of 1.0 mm or less, and preferably between 0.03 and 0.5 mm. The nozzle body is comprised of a material having 20% or less porosity and containing 50% or more open pores, each having a diameter of 5 .mu.m or less.

Abstract: An immersion nozzle for continuous casting of molten steel, which comprises: a nozzle body comprising an aluminagraphite refractory and a refractory layer excellent in erosion resistance against a molten mold power, said refractory layer being arranged so as to be integral with said nozzle body and flush with the outer surface of said nozzle body at the outside portion of said nozzle body in contact, when the lower portion of said immersion nozzle being immersed into molten steel in a mold, with a molten mold powder layer on the meniscus of said molten steel; said refractory layer arranged at said outside portion of said nozzle body consisting essentially of, in weight percentage;Carbon (C): from 2 to 10%,Zirconia (ZrO.sub.2): from 70 to 90%,At least one compound selected from the group consisting of silicon carbide (SiC) and amorphous silica (SiO.sub.2): from 5 to 27% and,Incidental impurities: up to 3%.