Characterization of the microstructure of the fusion zone of an Alloy 600-82 weld joint was conducted, with focus on the weld residual strain distribution and the comparison of the microstructure of heat affected zone...Characterization of the microstructure of the fusion zone of an Alloy 600-82 weld joint was conducted, with focus on the weld residual strain distribution and the comparison of the microstructure of heat affected zone （HAZ） with that of cold worked alloy. Peak of the residual strain was observed to approach to the fusion boundary in HAZ while the strain increased from the top of the weld to the root. Strain distribution in the HAZ was found to be concentrated adjacent to grain boundaries （GBs）, with a peak of approximately three times of that in grain. Further, triple junctions of the GB appear to cause a higher strain concentration than single GBs. The microstructure of HAZ consists of partially tangled dislocations, which is different from slip bands of high density dislocations in cold worked alloy. This may cause a relatively higher intergranular cracking resistance of HAZ due to the difficulty in transferring tangled dislocations to GB in HAZ under deformation.展开更多
Inconel 600 alloy is widely utilized for high temperature environment application due to the corresponding good oxidation and corrosion resistance properties.In order to estimate the high temperature oxidation resista...Inconel 600 alloy is widely utilized for high temperature environment application due to the corresponding good oxidation and corrosion resistance properties.In order to estimate the high temperature oxidation resistance of Inconel 600 alloy at various temperatures,the oxidation weight gain of all specimens was measured and fitted for the curve at the temperatures of 700,800 and 900 ℃ for exposure time of 100 h.The surface morphology and the component of the oxide film were analyzed by scanning electron microscopy(SEM),energy-dispersive spectroscopy(EDS) and X-ray diffraction(XRD).The results indicate that the high temperature oxidation resistance of Inconel 600 alloy is excellent blew 800℃ due to the oxidation kinetic curves at different temperatures corresponding to the parabola dynamic rules.This means that the oxidation film protects the substrate well.The dense oxide layer formation containing Cr_(2)O_(3) and NiCr_(2)O_(4) at 700 and 800 ℃ and MnCr_(2)O_(4) at 900 ℃,respectively,is the main reason for the good oxidation resistance.In contrast,the oxide layer peels off easily under applied force as the temperature increases beyond 800℃, on account of the complicated compositions of the oxide film and the binding force between the oxide layer and the substrate weakening.Corresponding oxidation mechanism is expected to be understood and the oxidation resistance of Inconel 600 alloy is improved through binding force enhancement.展开更多
基金financially supported by the Hundred-Talent Program of Chinese Academy of Sciences
文摘Characterization of the microstructure of the fusion zone of an Alloy 600-82 weld joint was conducted, with focus on the weld residual strain distribution and the comparison of the microstructure of heat affected zone （HAZ） with that of cold worked alloy. Peak of the residual strain was observed to approach to the fusion boundary in HAZ while the strain increased from the top of the weld to the root. Strain distribution in the HAZ was found to be concentrated adjacent to grain boundaries （GBs）, with a peak of approximately three times of that in grain. Further, triple junctions of the GB appear to cause a higher strain concentration than single GBs. The microstructure of HAZ consists of partially tangled dislocations, which is different from slip bands of high density dislocations in cold worked alloy. This may cause a relatively higher intergranular cracking resistance of HAZ due to the difficulty in transferring tangled dislocations to GB in HAZ under deformation.
基金financially supported by the National Key Research and Development Program of China(No.2012AA03A501)。
文摘Inconel 600 alloy is widely utilized for high temperature environment application due to the corresponding good oxidation and corrosion resistance properties.In order to estimate the high temperature oxidation resistance of Inconel 600 alloy at various temperatures,the oxidation weight gain of all specimens was measured and fitted for the curve at the temperatures of 700,800 and 900 ℃ for exposure time of 100 h.The surface morphology and the component of the oxide film were analyzed by scanning electron microscopy(SEM),energy-dispersive spectroscopy(EDS) and X-ray diffraction(XRD).The results indicate that the high temperature oxidation resistance of Inconel 600 alloy is excellent blew 800℃ due to the oxidation kinetic curves at different temperatures corresponding to the parabola dynamic rules.This means that the oxidation film protects the substrate well.The dense oxide layer formation containing Cr_(2)O_(3) and NiCr_(2)O_(4) at 700 and 800 ℃ and MnCr_(2)O_(4) at 900 ℃,respectively,is the main reason for the good oxidation resistance.In contrast,the oxide layer peels off easily under applied force as the temperature increases beyond 800℃, on account of the complicated compositions of the oxide film and the binding force between the oxide layer and the substrate weakening.Corresponding oxidation mechanism is expected to be understood and the oxidation resistance of Inconel 600 alloy is improved through binding force enhancement.
