In order to achieve good mechanical properties of Al-Cu alloys such as high strength and good toughness,precipitation hardening and artificial aging treatment were applied.As defined by the T6 heat treatment,the stand...In order to achieve good mechanical properties of Al-Cu alloys such as high strength and good toughness,precipitation hardening and artificial aging treatment were applied.As defined by the T6 heat treatment,the standard artificial aging treatment for Al-Cu alloy followed heat treatments of solution treatment at 510-530 ℃ for 2 h,quenching in water at 60 ℃ and then artificial aging at 160-190 ℃ for 2-8 h.The effects of solution treatment and artificial aging on the microstructure and mechanical properties of Al-Cu alloy were studied by optical microscopy（OM）,scanning electron microscopy（SEM）,energy dispersive X-ray spectroscopy（EDS）,transmission electron microscopy（TEM） and tensile test.The results of solution treatment indicate that the mechanical properties of Al-Cu alloy increase and then decrease with the increase of solution temperature.This is because the residual phases dissolve gradually into the matrix,and the fraction of the precipitation and the size of the re-crystallized grain increased.Compared to the solution temperature,the solution holding time has less effect on the microstructure and the mechanical properties of Al-Cu alloy.The artificial aging treatments were conducted at 160-180 ℃ for 2-8 h.The results show that the ultimate tensile strength can be obtained at 180 ℃ for 8 h.Ultimate tensile strength increased with increasing time or temperature.Yield strength was found as the same as the ultimate tensile strength result.展开更多
Dual-Phase (DP) steels are made of ductile ferrite phase and hard martensite phase.Although it became crucial in progress of automotive industry to save fuel consumption and reduce total weight of vehicles,we need mor...Dual-Phase (DP) steels are made of ductile ferrite phase and hard martensite phase.Although it became crucial in progress of automotive industry to save fuel consumption and reduce total weight of vehicles,we need more accurate estimation of distribution to mechanical properties in total amounts of specimen.DP steels have considerable difference of mechanical levels in each phase including ferrite and martensite.That is why this study focuses on deconvolution of experimental tensile curve into ferrite and martensite using EBSD for calculation of phase volume fractions and Swift equation.Nanoindentation for certain parameter of each phase was conducted to produce the deconvolution curves.展开更多
文摘In order to achieve good mechanical properties of Al-Cu alloys such as high strength and good toughness,precipitation hardening and artificial aging treatment were applied.As defined by the T6 heat treatment,the standard artificial aging treatment for Al-Cu alloy followed heat treatments of solution treatment at 510-530 ℃ for 2 h,quenching in water at 60 ℃ and then artificial aging at 160-190 ℃ for 2-8 h.The effects of solution treatment and artificial aging on the microstructure and mechanical properties of Al-Cu alloy were studied by optical microscopy（OM）,scanning electron microscopy（SEM）,energy dispersive X-ray spectroscopy（EDS）,transmission electron microscopy（TEM） and tensile test.The results of solution treatment indicate that the mechanical properties of Al-Cu alloy increase and then decrease with the increase of solution temperature.This is because the residual phases dissolve gradually into the matrix,and the fraction of the precipitation and the size of the re-crystallized grain increased.Compared to the solution temperature,the solution holding time has less effect on the microstructure and the mechanical properties of Al-Cu alloy.The artificial aging treatments were conducted at 160-180 ℃ for 2-8 h.The results show that the ultimate tensile strength can be obtained at 180 ℃ for 8 h.Ultimate tensile strength increased with increasing time or temperature.Yield strength was found as the same as the ultimate tensile strength result.
文摘Dual-Phase (DP) steels are made of ductile ferrite phase and hard martensite phase.Although it became crucial in progress of automotive industry to save fuel consumption and reduce total weight of vehicles,we need more accurate estimation of distribution to mechanical properties in total amounts of specimen.DP steels have considerable difference of mechanical levels in each phase including ferrite and martensite.That is why this study focuses on deconvolution of experimental tensile curve into ferrite and martensite using EBSD for calculation of phase volume fractions and Swift equation.Nanoindentation for certain parameter of each phase was conducted to produce the deconvolution curves.
