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Oxide dispersion strengthened (ODS) iron-based high temperature alloy has good high-temperature mechanical properties of high temperature creep properties . This article prepared by MA process of Fe-12Cr-2.5W-0.4Ti-0.25Y 2 O 3 high temperature alloy powder , and then using the hydrogen reduction annealing , molding and sintering fabricated Fe - 12Cr -2.5W - 0.4Ti - 0.25Y 2 O 3 high-temperature alloy sintered body using X-ray diffraction analyzer ( XRD ) , optical microscopy ( OM), scanning electron microscopy (SEM), transmission electron microscopy ( TEM ) , energy spectrum analysis instrument ( EDS ) , differential thermal analysis instrument ( DTA ) , microhardness tester , electronic tensile machine test analysis means , study milling time and annealing temperature alloy powder characteristics and compression molding and sintering processes affect the performance of sintered alloy . With the increase in the mechanical alloying time , the Fe -12Cr - 2.5W - 0.4Ti - 0.25y 2 O 3 grain size of the α-Fe alloy powder gradually decreases , grain size after milling 24h reached the nanometer level ( 11.3nm ) , to continue to extend the milling time , grain size stabilized the milling 90h , the grain size of 8.4nm . Longer milling time , W, Cr is gradually dissolved in the α-Fe alloy powder gradually become lamellar morphology from the initial particulate , and then become equiaxed and then further refinement , when the milling time is 90h , the particle size of 3μm. Microhardness of the alloy powder increases with increasing milling time the microhardness reached 990.1 milling time 90h . Annealing can significantly reduce the degree of hardening of the powder , and annealing temperature so that the original powder particles becomes large in size . The alloy powder after annealing at 900 ℃ density after the suppression by the different pressing pressure increases with increasing pressure , the 800MPa pressed powder compacts to the relative density of 72.8% . Zinc stearate lubricant , the ejection pressure and suppress the pressure ratio of the correlation coefficient of 0.071 . When the sintering temperature of 1300 ° C , the mechanical properties of the sintered alloy , tensile strength 410.3MPa. Cr-rich phase , through analysis , the precipitated phase may be of σ phase precipitates in the alloy during the sintering process , resulting in higher hardness of the sintered alloy , the microhardness reached 728.7 .
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