| The article shows the preparation of Fe3Al ordered alloy by way of SHS non-equilibrium method and foundry equilibrium preparation method. The product's phase, microstructure, fracture morphology and its hardness are researched through XRD,SEM, optical microscope and sclerometer.For low discharge heat combustion synthesis system - Fe/A 1 mixed powder combustion synthesis, when proper activation method is adopted. The intermetallic compound bulk material of certain density will be produced. The research shows:1.to increase the relative density of pre-condensed semifinished product appropriately would be favorable for combustion synthesis reaction of the system.2.under certain temperature, to increase the pre-heated temperature would be favorable for the combustion synthesis reaction.3.during the certain time, the longer the mechanical ball milling time is, the more favorable for combustion synthesis reaction of the system.To make use of all the activation methods together, thermal explosion reaction occurs in the Fe/A 1 mixed powder combustion synthesis system. But that results the high void ratio, low density, hardness, and quality bulk material.By use of high-frequency induction furnace and equilibrium preparation - foundry method, the Fe- Al intermetallic compound has higher hardness and density. However, it is crassitude dendritic organism and dendritic sogregation exists. To make use of annealing at 1000C within 15h, dendritic disappears and fine even organism available. Then combined with mid- temperature heat treatment technique, we get FeCrAl based solid solution, FeCr dispersion phase double phase alloy with high hardness, good mechanics quality. But the alloy has worse room temperature plasticity, ductility and shows cleavage fracture both in casting and heat treatment.Research also shows we get better quality of non- equilibrium preparation method FeaAl bulk material than of equilibrium preparation method Fe3Al intermetallic compound alloy. |
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