Effect Of Fe On The Structure And Property Of Sub-rapidly Solidified High Aluminum Bronze Alloys

In this paper, sub-rapidly solidified bars of Cu-15Al-XFe （X=0,1,4,7,10,12,15）alloys were prepared by vacuum suction casting. The effect of iron content onmicrostructure, distribution of element, phase composition, thermal stability, hardness,and wear resistance of Cu-15Al-XFe （X=0,1,4,7,10,12,15） alloys was studied withoptical microscopy（OM）, scanning electron microscope（SEM）, energy dispersivespectrometer（EDS）, X-ray diffraction（XRD）, differential scanning calorimeter（DSC）,hardness tester, universal friction and wear tester. Corrosion behaviors of the alloyswere analyzed by immersion and electrochemical experiments in3.5%NaCl solutionand5.0%H₂SO₄solution.It was found that the iron content has great influence on the microstructure ofsub-rapidly solidified high aluminum bronze alloys. With the increase of Fe content, themicrostructure of alloys are transformed from columnar grains to equiaxed grains. Theresults showed based on XRD analysis that when the w（Fe）≤7%, the microstructure ofalloys consists of2＋（α+γ₂）; when the w（Fe）≥10%, the microstructure of alloys iscomposed of （α+γ₂）＋. The volume fraction of phase increases gradually with Fecontent and phase becomes coarsening. phase compositions in microstructure of alloysare agreement with Energy Spectrum Analysis results.DSC results indicated that solid-liquid phase transition temperature is increasedfrom1045℃to1080℃when the Fe content increases from1%to15%, whichimproves solid-liquid phase transition temperature of the alloys.Hardness tests results showed that the hardness of alloys is increased at first andthen decreased with Fe addition increasing, and the maximum hardness value reaches492HV. The friction and wear test results showed that alloys has bigger loss and lowerfriction coefficient under higher sliding speed and heavier load condition compared withthe lower sliding speed and lighter load. With increasing of Fe content, wear mass lossof alloys first decreases and then increases under dry sliding friction condition. Theresults indicate that the alloys have better wear resistance at low content of Fe.When thecontent of Fe is4%, alloy has the best comprehensive mechanical properties.The corrosion test results showed that Cu-15Al-XFe （X=0,1,4,7,10,12,15） alloys suffer a dealuminization and deferrization corrosion in3.5%NaCl and5.0%H₂SO4solution. The corrosion resistance of alloys decreases as the increase of Fe content.