Room temperature and high temperature microstructural and mechanical properties of arc melted Ni Al-28Cr-6Mo eutectic alloys doped with 0.1% Fe, 0.2% Fe and 0.5% Fe(mole fraction) were investigated. The homogenization...Room temperature and high temperature microstructural and mechanical properties of arc melted Ni Al-28Cr-6Mo eutectic alloys doped with 0.1% Fe, 0.2% Fe and 0.5% Fe(mole fraction) were investigated. The homogenization heat treatment of the alloys was conducted at 1300℃ in Ar atmosphere. Microscopic analyses, hardness measurements, XRD measurements and compression tests were used to characterize the alloys. As-cast and homogenized alloys exhibit fine cellular eutectic structures with coarse intercellular eutectic structure. The increase in the content of Fe results in coarsening eutectic layers and the decrease in eutectic cells. All alloys have very high compressive stress and strain at room temperature. The addition of Fe has small negative impact on the strength and ductility of the alloys at room temperature. However, the addition of Fe increases the high temperature strength of the alloy. High temperature XRD patterns show that peaks shift to lower Bragg angles. This indicates that the lattice parameter of the alloys increases.展开更多
Morphology,distribution,composition,forming ability,structural stability and intrinsic mechanical properties of the intermetallic compounds(IMCs)formed in steel/aluminum laser welding were determined through scanning ...Morphology,distribution,composition,forming ability,structural stability and intrinsic mechanical properties of the intermetallic compounds(IMCs)formed in steel/aluminum laser welding were determined through scanning electron microscope,energy dispersive spectrometer,X-ray diffractometer and first-principles calculation.It was found that the mechanical properties of the joint are limited by the Fe−Al IMCs,whose brittleness is attributed to the orbital hybridization between Al(s),Al(p)and Fe(d).However,the joint properties are improved by adding interlayer,which is ascribed to some changes of electronic structure of the generated IMCs.The transition mechanism of IMCs changing from brittle to ductile is mainly due to the weak ability of interlayer elements to attract electrons.The mechanical properties of the joint are closely related to the ductility or brittleness of the IMCs.Moreover,the addition of Ti foil interlayer effectively improves the mechanical properties of the joints,which means that the experimental verification is in good agreement with the theoretical calculation predictions.展开更多
基金Tubitak for their financial support under Contract No. 213M247
文摘Room temperature and high temperature microstructural and mechanical properties of arc melted Ni Al-28Cr-6Mo eutectic alloys doped with 0.1% Fe, 0.2% Fe and 0.5% Fe(mole fraction) were investigated. The homogenization heat treatment of the alloys was conducted at 1300℃ in Ar atmosphere. Microscopic analyses, hardness measurements, XRD measurements and compression tests were used to characterize the alloys. As-cast and homogenized alloys exhibit fine cellular eutectic structures with coarse intercellular eutectic structure. The increase in the content of Fe results in coarsening eutectic layers and the decrease in eutectic cells. All alloys have very high compressive stress and strain at room temperature. The addition of Fe has small negative impact on the strength and ductility of the alloys at room temperature. However, the addition of Fe increases the high temperature strength of the alloy. High temperature XRD patterns show that peaks shift to lower Bragg angles. This indicates that the lattice parameter of the alloys increases.
基金the National Natural Science Foundation of China(Nos.51674112,51774125).
文摘Morphology,distribution,composition,forming ability,structural stability and intrinsic mechanical properties of the intermetallic compounds(IMCs)formed in steel/aluminum laser welding were determined through scanning electron microscope,energy dispersive spectrometer,X-ray diffractometer and first-principles calculation.It was found that the mechanical properties of the joint are limited by the Fe−Al IMCs,whose brittleness is attributed to the orbital hybridization between Al(s),Al(p)and Fe(d).However,the joint properties are improved by adding interlayer,which is ascribed to some changes of electronic structure of the generated IMCs.The transition mechanism of IMCs changing from brittle to ductile is mainly due to the weak ability of interlayer elements to attract electrons.The mechanical properties of the joint are closely related to the ductility or brittleness of the IMCs.Moreover,the addition of Ti foil interlayer effectively improves the mechanical properties of the joints,which means that the experimental verification is in good agreement with the theoretical calculation predictions.
