A microwave furnace has a furnace chamber formed between a chamber housing and a sintering platform for an object to be sintered. A microwave source is arranged for emitting microwaves into the furnace chamber. The microwave furnace further has a susceptor that comprises a material which over a temperature range of the material of at least 23 C to 700 C couples into microwaves. The susceptor and the furnace chamber are movable relative to each other between a first position, in which the susceptor is positioned relative to the furnace chamber, and a second position in which the susceptor is positioned further retracted from the furnace chamber relative to the first position. The invention helps providing a zirconia material with a relative homogeneous material structure.