A novel experimental approach was presented, namely the overlapping elliptical bulge test, which can load and research thickness normal stress. Theoretical analysis model of the overlapping elliptical bulging was desc...A novel experimental approach was presented, namely the overlapping elliptical bulge test, which can load and research thickness normal stress. Theoretical analysis model of the overlapping elliptical bulging was described, the equivalent stress?strain curves of target sheets with different ellipticity ratios were determined experimentally, and influences of the material performance and thickness of overlapping sheets on the flow property of the target sheet were also researched. The results show that, in the overlapping hydraulic bulge test, the equivalent stress?strain curve can be determined up to larger strains before necking than in the no overlapping hydraulic bulge test. And as the die ellipticity ratio decreases, the flow stress curves tend to move away from the curve obtained by circular (b/a=1) bulging test. Meanwhile, the flow property of the target sheet can be improved by choosing higher strength coefficient K, larger work hardening exponent n and proper thickness of the overlapping sheet.展开更多
The effects of rare earth metal salts (REMs), cerium(IV) salt and lanthanum (III) salt, on the property of anodized coating of LD10 aluminum alloy are studied by corrosion tests including neutral salt spray test and c...The effects of rare earth metal salts (REMs), cerium(IV) salt and lanthanum (III) salt, on the property of anodized coating of LD10 aluminum alloy are studied by corrosion tests including neutral salt spray test and copper accelerated acetic acid immersion test, polarization curves measurement, energy dispersion analyzer of X-Ray(EDAX) analysis, and in situ ellipsometry. The results show that the addition of either of the two REMs in anodizing solution hardly changes the composition of an anodized coating, while increases the thickness of barrier part and reduces the porosity of porous part, which contributed to the improvement of the corrosion resistance of the anodized coating. The results also demonstrate that the effect of cerium salt was better than that of lanthanum salt.展开更多
基金Project(2014ZX04002041)supported by the National Science and Technology Major Project,ChinaProject(51175024)supported by the National Natural Science Foundation of China
文摘A novel experimental approach was presented, namely the overlapping elliptical bulge test, which can load and research thickness normal stress. Theoretical analysis model of the overlapping elliptical bulging was described, the equivalent stress?strain curves of target sheets with different ellipticity ratios were determined experimentally, and influences of the material performance and thickness of overlapping sheets on the flow property of the target sheet were also researched. The results show that, in the overlapping hydraulic bulge test, the equivalent stress?strain curve can be determined up to larger strains before necking than in the no overlapping hydraulic bulge test. And as the die ellipticity ratio decreases, the flow stress curves tend to move away from the curve obtained by circular (b/a=1) bulging test. Meanwhile, the flow property of the target sheet can be improved by choosing higher strength coefficient K, larger work hardening exponent n and proper thickness of the overlapping sheet.
文摘The effects of rare earth metal salts (REMs), cerium(IV) salt and lanthanum (III) salt, on the property of anodized coating of LD10 aluminum alloy are studied by corrosion tests including neutral salt spray test and copper accelerated acetic acid immersion test, polarization curves measurement, energy dispersion analyzer of X-Ray(EDAX) analysis, and in situ ellipsometry. The results show that the addition of either of the two REMs in anodizing solution hardly changes the composition of an anodized coating, while increases the thickness of barrier part and reduces the porosity of porous part, which contributed to the improvement of the corrosion resistance of the anodized coating. The results also demonstrate that the effect of cerium salt was better than that of lanthanum salt.
