Chart of PO<inf>2</inf>versus temperature and oxidation degree for Mn-Zn ferrites in the composition range: 50 < Fe<inf>2</inf>O<inf>3</inf>< 54; 20 < MnO < 35; 11 < ZnO < 30 (mole %)

Development of MnZn ferrites by combinatorial synthesis and high throughput screening method

“…3 corresponding to the above sintering temperatures. Different with literature [13], the oxygen concentration will be reduced from 20.6% to 0.1% at about 900 • C, moreover, keep the value 0.1% for half an hour, then at about 1100 • C, the oxygen concentration begins to increase. The aim of this procedure is to effectively prevent the samples broken during quick increase of temperatures.…”

Nanocrystalline Mn–Zn ferrites from mixed oxalates: Synthesis, stability and magnetic properties

“…Spinel-type ferrites in the system Mn-Zn-Fe-O in air are stable at high temperatures only and decompose into a mixture of haematite, ␣-Fe 2 O 3 , and a Fe-poor spinel during cooling [25,26]. To test for the metastability of the spinel ferrite at 500 • C, a sample of the mixed oxalate was annealed at 500 • C for 24 h. In that case, we indeed observed the expected mixture of haematite/spinel (Fig.…”

Materials processing issues influencing the frequency stability of the initial magnetic permeability of MnZn ferrites

“…Subsequently, during the residual dwell time and the entire cooling stage, the partial pressure of oxygen ͑PO 2 ͒ is set to obey the equilibrium pattern dictated by the well known relation log PO 2 = C 1 / T + C 2 , where T is the temperature and C 1 and C 2 are constants. 15 The constants C 1 and C 2 are kept identi-cal in all sintering schedules. In every sintering experiment, reference specimens, from material with known properties, are also sintered.…”