MORPHOLOGY AND STRUCTURE OF TRANSFORMATION PRODUCTS FORMED AT INTERMEDIATE TEMPERATURE IN A Cu-Zn-A1 ALLOY"

来源期刊：中国有色金属学报(英文版)1992年第2期

论文作者：Lu,Wei Jiang,Bohong Xu,Zuyao

文章页码：51 - 55

Key words：Cu-Zn-A1 alloy ; transformation at intermediate temperature; morphology and structure

Abstract: A TTT diagram for the precipitation formed at some intermediate temperatures through cooling from high temperature parent phase in a Cu-27.27Zn-3.73A1 alloy is established by means of dilatometric measurement. The morphology and structure of transformation products formed at some intermediate temperatures isothermally through cooling from high temperature parent phase and up-quenching from DO₃ 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 α, plate-like bainite and α rods, and bainite plates. Prolonged aging makes bainite plate change gradually into αwhose lattice parameters are no different from that of αformed equilibriumly from parent phase. The structure is almost orthorhombic long period structure for bainites formed from B₂ and DO₃ parent phase, but monoclinic for martensite from DO₃. They correspond to the overlapping and separating of (1 2 10) and (2 0 10) diffraction peaks respectively, showing the lower degree of ordering in bainite