Transmission electron microscopy(TEM),X-ray diffraction(XRD),electron backscattered diffraction(EBSD),and tensile tests were used to study the effects of strain rates(0.1,1 and 9.1 s^(-1))on the microstructure and mec...Transmission electron microscopy(TEM),X-ray diffraction(XRD),electron backscattered diffraction(EBSD),and tensile tests were used to study the effects of strain rates(0.1,1 and 9.1 s^(-1))on the microstructure and mechanical properties of spray-formed Al-Cu-Mg alloys during large-strain rolling at 420℃.Results show that during hot rolling,the proportion of high-angle grain boundaries(HAGBs)and the degree of dynamic recrystallization(DRX)initially increase and then decrease,whereas the average grain size and dislocation density show the opposite trend with the increase of the strain rate.In addition,the number of S′phases in the matrix decreases,and the grain boundary precipitates(GBPs)become coarser and more discontinuous as the strain rate increases.When the strain rate increases from 0.1 to 9.1 s^(-1),the tensile strength of the alloy decreases from 492.45 to 427.63 MPa,whereas the elongation initially increases from 12.1%to 21.8%and then decreases to 17.7%.展开更多
The impact of cold rolling deformation,which was introduced after solid solution and before aging treatment,on microstructure evolution and mechanical properties of the as-extruded spray formed Al−9.8Zn−2.3Mg−1.73Cu−0...The impact of cold rolling deformation,which was introduced after solid solution and before aging treatment,on microstructure evolution and mechanical properties of the as-extruded spray formed Al−9.8Zn−2.3Mg−1.73Cu−0.13Cr(wt.%)alloy,was investigated.SEM,TEM,and EBSD were used to analyze the microstructures,and tensile tests were conducted to assess mechanical properties.The results indicate that the D1-T6 sample,subjected to 25%cold rolling deformation,exhibits finer grains(3.35μm)compared to the D0-T6 sample(grain size of 4.23μm)without cold rolling.Cold rolling refines the grains that grow in solution treatment.Due to the combined effects of finer and more dispersed precipitates,higher dislocation density and smaller grains,the yield strength and ultimate tensile strength of the D1-T6 sample can reach 663 and 737 MPa,respectively.In comparison to the as-extruded and D0-T6 samples,the yield strength of the D1-T6 sample increases by 415 and 92 MPa,respectively.展开更多
基金financially supported by the Major Special Projects in Anhui Province,China(No.202003c08020005)the Key Projects in Hunan Province,China(No.2020GK2045)。
文摘Transmission electron microscopy(TEM),X-ray diffraction(XRD),electron backscattered diffraction(EBSD),and tensile tests were used to study the effects of strain rates(0.1,1 and 9.1 s^(-1))on the microstructure and mechanical properties of spray-formed Al-Cu-Mg alloys during large-strain rolling at 420℃.Results show that during hot rolling,the proportion of high-angle grain boundaries(HAGBs)and the degree of dynamic recrystallization(DRX)initially increase and then decrease,whereas the average grain size and dislocation density show the opposite trend with the increase of the strain rate.In addition,the number of S′phases in the matrix decreases,and the grain boundary precipitates(GBPs)become coarser and more discontinuous as the strain rate increases.When the strain rate increases from 0.1 to 9.1 s^(-1),the tensile strength of the alloy decreases from 492.45 to 427.63 MPa,whereas the elongation initially increases from 12.1%to 21.8%and then decreases to 17.7%.
基金the support from the National Natural Science Foundation of China(No.52271177)the Science and Technology Innovation Leaders Projects in Hunan Province,China(No.2021RC4036).
文摘The impact of cold rolling deformation,which was introduced after solid solution and before aging treatment,on microstructure evolution and mechanical properties of the as-extruded spray formed Al−9.8Zn−2.3Mg−1.73Cu−0.13Cr(wt.%)alloy,was investigated.SEM,TEM,and EBSD were used to analyze the microstructures,and tensile tests were conducted to assess mechanical properties.The results indicate that the D1-T6 sample,subjected to 25%cold rolling deformation,exhibits finer grains(3.35μm)compared to the D0-T6 sample(grain size of 4.23μm)without cold rolling.Cold rolling refines the grains that grow in solution treatment.Due to the combined effects of finer and more dispersed precipitates,higher dislocation density and smaller grains,the yield strength and ultimate tensile strength of the D1-T6 sample can reach 663 and 737 MPa,respectively.In comparison to the as-extruded and D0-T6 samples,the yield strength of the D1-T6 sample increases by 415 and 92 MPa,respectively.
