Flat sintered copper and copper-zirconia substrates, with zirconia nanoparticles contents of 1 and 3 vol%, were produced by aqueous tape casting and controlled sintering. Aqueous suspensions were prepared to a solid content of 58 vol% using 3 wt% commercial binder emulsion. The green tapes were treated at 350 ºC in air to remove organics and sintered at temperatures ranging from 800 to 1000 ºC in atmosphere of Ar/5%H 2 . Copper tapes reached almost full densification at 900 ºC. Composite with 1 vol% zirconia, sintered at 800 ºC, maintained high density and provided a noticeable increase of the mechanical strength, whereas further additions up to 3 vol% reduced the densification and the resulting mechanical performance became poorer.