A TTT diagram for th ie precipitation formed at some intermediate temperatures through cooling from high lemperalure parenl phase in a Cu-27 27Zn-3.73Al allay is established by means of dilatormetric measurement.The m...A TTT diagram for th ie precipitation formed at some intermediate temperatures through cooling from high lemperalure parenl phase in a Cu-27 27Zn-3.73Al allay is established by means of dilatormetric measurement.The morphology and structure of transformation products formed at some intermediate tem peratures isothermally through cooling from high temperature parent phase and up-quenching from DO_(3) parent phase are studied by metallographic.X-ray and electron microscopy analyses.Three regions in the two separate C curves are obtained according to different morphology of precipitate:rod-like a,plate-like bainite and a rods,and bainite plates.Prolonged aging makes bainite plate change gradually into a whose lattice parameters are no different from that of a formed equilibriumly from parent phase.The structure is almost orthorhombic long period structure for bainites formed from B_(2) and DO_(3) parent phase,but monoclinic for martensite from DO_(3).They correspond to the overlapping and separating of(1210)and(2010)diffraction peaks respectively,showing the lower degree of ordering in bainite.展开更多
TTT diagrams and kinetics curves of bainite formation through up quenching from martensitic slate and of dilatometry and cooling from high temperature parent phase in Cu-Zn-Al alloys are established by ments of dilato...TTT diagrams and kinetics curves of bainite formation through up quenching from martensitic slate and of dilatometry and cooling from high temperature parent phase in Cu-Zn-Al alloys are established by ments of dilatometry and metallographic inspection.Experimental results show that the kinetics characteristics of bainite formation obey the Austin-Rickett Equation with n=2.25 for up-quenched specimens and n=1.80 for specimens cooled from high temperature,and the activation energy of bainite formation is about.110 kJ/mol,corresponding to that ofthe diffusion of solute atoms.展开更多
基金supported by the National Natural Science Foundation
文摘A TTT diagram for th ie precipitation formed at some intermediate temperatures through cooling from high lemperalure parenl phase in a Cu-27 27Zn-3.73Al allay is established by means of dilatormetric measurement.The morphology and structure of transformation products formed at some intermediate tem peratures isothermally through cooling from high temperature parent phase and up-quenching from DO_(3) parent phase are studied by metallographic.X-ray and electron microscopy analyses.Three regions in the two separate C curves are obtained according to different morphology of precipitate:rod-like a,plate-like bainite and a rods,and bainite plates.Prolonged aging makes bainite plate change gradually into a whose lattice parameters are no different from that of a formed equilibriumly from parent phase.The structure is almost orthorhombic long period structure for bainites formed from B_(2) and DO_(3) parent phase,but monoclinic for martensite from DO_(3).They correspond to the overlapping and separating of(1210)and(2010)diffraction peaks respectively,showing the lower degree of ordering in bainite.
文摘TTT diagrams and kinetics curves of bainite formation through up quenching from martensitic slate and of dilatometry and cooling from high temperature parent phase in Cu-Zn-Al alloys are established by ments of dilatometry and metallographic inspection.Experimental results show that the kinetics characteristics of bainite formation obey the Austin-Rickett Equation with n=2.25 for up-quenched specimens and n=1.80 for specimens cooled from high temperature,and the activation energy of bainite formation is about.110 kJ/mol,corresponding to that ofthe diffusion of solute atoms.
