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Notes: 0.85Pb(Zn1/3Nb2/3)O3-0.10BaTiO3-0.05PbTiO3 (abbreviated as PZN-based ceramicshereafter) ternary system ceramics with Zn2+ deficiency were synthesized by the columbite method.The effect of deficient Zn2+ on phase structure, ordered micro-region size and dielectric propertieswas investigated in detail. The analysis of Raman scattering spectra demonstrated that Zn2+ deficiencysharply enlarged the ordered micro-region size. Zn2+ deficiency significantly increased the dielectricconstant, and decreased the diffusion degree of phase transition. There is a close correlation betweeneffective ordered micro-regions size and dielectric properties for the PZN-based ceramics

Notes: The evolution of second phases and its effect on tensile mechanical property in artificialageing and RRA process of super-high strength aluminum alloy is investigated.The result of tensiletest shows that the samples of Al-Zn-Mg-Cu-Ag alloy aged at lower temperature(100℃) not onlyhave higher tensile strength up to 753Mpa but also relatively higher tensile elongation above 9% thannormal temperature(120℃) in artificial ageing. The sample of Al-Zn-Mg-Cu alloy has the highesttension strength upto 788Mpa when aged at 100℃ for 48 hours in single step of artificial ageing.Further more in RRA process samples of Al-Zn-Mg-Cu alloy preaged at 100℃ for 24 hoursretrogressed at 200℃ for 7min and reaged at 100℃for 24 hours present the best tensile strength of795Mpa than others. The tensile strength of Al-Zn-Mg-Cu alloy after RRA treated decreases withprolonging of retrogression time and reageing time starting from 7mins and 24 houres respectively.SEM observation shows that crack of the samples in tensile test is created at large particles in thefracture while there are more particles of undissolved phase in Al-Zn-Mg-Cu alloy containing Ag.TEM observation shows that the dominant strengthening particle corresponding to the peak strengthof Al-Zn-Mg-Cu alloy containing Ag when aged at 120℃ for 8 hours is η’ phase while dominantstrengthening particle is G.P zone when aged at 100℃ for 80 hours. However, η’ phase as thedominant strengthening particles corresponds to the peak strength of Al-Zn-Mg-Cu alloy withoutcontent of Ag when aged at 100℃ for 48hours. TEM observation also shows that G.P zone asstrengthening particle is dominant in the samples of Al-Zn-Mg-Cu alloy reaged at 100℃ for 24hours, and strengthening particles is coarsened when the sample is retrogressed at 200℃ and reagedfor a longer time. It is suggested that whether at the presence of coarse particles of undissolved phasesor when G.P zone and η’ particle grow up in the retrogression ,sample needs deformable G.P zoneinstead of undeformable η’ in subsequent artificial ageing and reageing as dominant strengtheningparticle, in order to present a larger freedom spacing for dislocation to slip and let the sample not tobehave too brittle to display high resistance to imposed plastic deformation or high tensile strength

Notes: The alloying behavior of RE element of Er in Al-Cu-Mg-Ag alloys with addition of Er wereinvestigated in this paper. During solidification ,most of element Er segregated at grain boundaries inthe form of primary Al8Cu4Er phase and part of Er dissolved in the α-Al matrix. After rolling,Al8Cu4Er phase could be fragmentated into dispersed particle which leaded to an increase of thegrain boundary strengthening . TEM observation and tensile strength test showed that small additionof Er retarded the precipitation of Ω phase and prolonged the time corresponding to the peakaging,with a remarkable increase of ductility