Abstract: In this paper,the ash fusion characteristics and mineral behavior of individual coal ash and a series of two-component blendsd ashes are studied.The samples are heated progressively from(IT)at 100?℃intervals in reducing atmosphere.Mineral composition and type at each temperature interval are determined by X-ray diffraction (XRD)analysis.For different coal ashes,the main mineral matter at 800?℃is quartz,anhydrite and hematite,calcite and feldspar.With increasing temperature,oxidation,thermal decomposition,transformation and reaction occur between the components.It can be seen that quartz,anhydrite decrease and anorthite,gehlenite increase.At about 1200?℃,all of mineral diminish and a glass phase is formed.Some combinations of mineral in component coal produce low-melting eutectic composition at a high temperature and this is the main reason causing the non-arithmetic average of softening temperature of blends ash.