Korea has proposed and designed a Helium Cooled Molten Lithium (HCML)Test Blanket Module (TBM) to be tested in the International Thermonuclear Experimental Reactor (ITER). Ferrite Martensitic (FM) steel is designed to be used as a structural material in this design. Three mock-ups, especially for the first wall channels, were fabricated with a Hot Isostatic Pressing (HIP, 1050 degrees C, 100 MPa, 2 h) in order to develop the fabrication technology. One of them was used to observe the microstructure and it was found that there are no pores and cracks. Other mock-ups were used with high heat flux (HHF) tests performed with 20 cycles under 0.5 and 1.0 MW/m(2) heat fluxes in order to evaluate the integrity of the fabricated mock-ups. Here. HHF test conditions were determined with an ANSYS-CFX analysis. And then, the mock-ups were tested and broken under a 1.5 MW/m(2) heat flux, which is about the Critical Heat Flux (CHF) at the wall. (C) 2009 Elsevier B.V. All rights reserved.