Microwave heated materials often reach a quasi-stable temperature resulting in thermal runaway. To control steady state in microwave processing, it is important to predict the quasi-stable temperature of the steady state. We demonstrated that the microwave heating behavior of hematite varies significantly with its initial temperature. In microwave heating, hematite samples could not be heated from room temperature, whereas hematite samples preheated to 410 degrees C or higher was heated to a temperature of 1020 degrees C. The microwave heating behavior can be accurately predicted by considering the steady-state energy balance. (c) 2013 Elsevier B.V. All rights reserved.