激光引燃合成Fe-Al掺杂Cr粉合金的组织及性能

Microstructure and Properties of Fe-Al Alloy Blended with Chromium Powder by Laser Ignition Synthesis

采用激光引燃自蔓延高温合成的方法,在Fe70Al30粉末中分别添加质量分数为0%、5%、10%、15%和20%的Cr粉,压制成坯,制备出Fe-Al复合材料。利用X射线衍射仪、金相显微镜等表征手段及孔隙率、硬度、磨损和腐蚀性能等性能测试方法,得到了不同Cr含量对烧结合金显微组织及性能的影响规律。结果表明:烧结合金主要物相为Fe_3Al、FeAl、AlCrFe_2、Al_8Cr_5、Al_2O_3和Cr_2O_3。随着Cr含量增加,合金的孔隙率先减小再增大,最小值为12.58%。当Cr含量为10%时,合金显微硬度最高,达到876.4HV,磨损率最低为0.65g/mm^2,自腐蚀电流密度最小为20.32mA/cm^2,耐腐蚀性能最好。

In order to obtain high performance Fe-Al alloy material,chromium powder with mass fraction of 0%,5%,10%,15%and 20%were added into Fe70 Al30 powder and Fe-Al based composite materials were prepared by laser ignition self-propagating high temperature synthesis.Effects of chromium powder content on microstructure and properties of sintered alloy were obtained by the means of microstructure characterization such as X-ray diffraction and optical microscope and performance test methods of porosity,hardness,wear resistance and corrosion resistance.It is found that the main product phases of the sintered alloy are Fe3Al、FeAl、AlCrFe2、Al8Cr5、Al2O3 and Cr2O3.With the increase of Cr content,the porosity of the alloy decreased first and then increased and the minimum is 12.58%.When the content of chromium powder is 10%,the microhardness of the sintered alloy is the highest,reaching 876.4 HV,the wear rate is lowest with 0.65 g/mm2,the corrosion current density is minimum with 20.32 mA/cm2,and the corrosion resistance is the best.