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A NEW MORPHOLOGY OF MARTENSITE
ZHONG Jiaxiang QI Yan Beijing Institute of Technology,Beijing,ChinaZHANG Xiumu GUO Yunyi Institute of Metal Research,Academia Sinica,Shenyang,China Beijing Institute of Technology,Beijing,China,
ZHONG Jiaxiang QI Yan Beijing Institute of Technology
,Beijing,ChinaZHANG Xiumu GUO Yunyi Institute of Metal Research,Academia Sinica,Shenyang,China Beijing Institute of Technology,Beijing,China

金属学报(英文版) , 1991,
Abstract: A new “mid-relief” plate martensite was observed together with lenticular plate and thinplate martensites in Fe-29.37Ni-0.34C alloy after twice stepped cooling:-100/-120℃,-120/-140℃,-155/-165℃ and -165/-196℃,by means of colour metallography andTEM.The morphology of martensites changes with decreasing M_s temperature.The“mid-relief” plate martensite is characterized by the intensive mid-relie and the substructuresof symmetric double twins or half twins and half dislocations,the formation of this martensitecan be interpreted by a stress-induced co-generated mechanism.
The morphology of lath martensite: a new perspective  [PDF]
Anton Muehlemann,Konstantinos Koumatos
Physics , 2015, DOI: 10.1051/matecconf/20153307003
Abstract: A mathematical framework is proposed to predict the features of the (5 5 7) lath transformation in low-carbon steels based on energy minimisation. This theory generates a one-parameter family of possible habit planes and a selection mechanism then identifies the (5 5 7) normals as those arising from a deformation with small atomic movement and maximal compatibility. While the calculations bear some resemblance to those of double shear theories, the assumptions and conclusions are different. Interestingly, the predicted microstructure morphology resembles that of plate martensite, in the sense that a type of twinning mechanism is involved.
MORPHOLOGY OF MARTENSITE IN 7CrSiMnMoV STEEL AND ITS STRENGTH-TOUGHNESS
WANG Ruixiang GU Nanju YIN Fuxing Hebei Institute of Technology,Tianjin,China,
WANG Ruixiang GU Nanju YIN Fuxing Hebei Institute of Technology
,Tianjin,China

金属学报(英文版) , 1991,
Abstract: The morphology and substructure of martensites in 7CrSMnMoV steel were observed under optical or electron microscope,and martensitic transformation with its morphology was also analysed.In the normally quenched steel three types of martensites are found,including the wide lath one of dislocation substructure formed preferentially along grain boundaries,the thinner inner laths and the twinning martensite plate in interior of grain.Therefore,an at- tempt was made to substitute lower bainite,formed by short-term isothermal quenching.for intergranular martensite,it is believed that the morphology would be very influential to the stength-toughness of the steel.
Regular Pattern of Morphology Transition in Mixed Martensite Structures
GONG Hai,ZHANG Xiumu,
贡海
,张修睦

材料科学技术学报 , 1990,
Abstract: The morphology and substructure of mixedmartensites in ferrous alloys have been examined byusing optical and transmission electron microscope.The results indicated that the main formation se-quence of martensitic morphology was butterfly→plate→lath,with decreasing forming temperatureswhen the plastic accommodation takes place in theparent phase,which is affected by the transforma-tion strain fiélds.It was shown that the martensitemorphology is not only decided by the formingtemperature alone,but also by the dislocation struc-ture in austenite before the transformation.
A NOTE ON RELATIONSHIP BETWEEN MARTENSITE MORPHOLOGY AND SHAPE MEMORY EFFECT OF A Cu-Al-Ni ALLOY

Tan Shusong,Huang Jianchao,Sun Xiaohua,Tan Xuecheng,

金属学报 , 1982,
Abstract: A direct observation under different temperature and stress is reported of the martensite morphology variation vs the longitudinal change in a Cu-Al-Ni alloy specimen. The results indicate that its pseudo-elasticity and shape memory effect are closely related to the variation of martensite morphology.
SUBSTRUCTURE AND CRYSTAL MORPHOLOGY OF MARTENSITE IN MEDIUM CARBON IRON ALLOYS
LIU Yumen HE Zhirong Xi''''an Jiaotong University,Xi''''an,China Professor,Deptof Materials Science,Engineering,Xi''''an Jiaotong University,Xi''''an,China,
LIU Yumen HE Zhirong Xi''''an Jiaotong University
,Xi''''an,China Professor,Dept.of Materials Science and Engineering,Xi''''an Jiaotong University,Xi''''an,China

金属学报(英文版) , 1989,
Abstract: The morphologic,substructural and crystallographic characteristics of martensite in steels 60 and 60Si2Mn have been investigated by means of optical and transmission electron microscopy combined with B-M phenomenological crystallographic theory.The average hab- it plane of martensite in medium carbon iron alloys is{225}_f.Experimental data on the habit plane and the orientation relationship between the austenite and martensite are in agreement with the B-M theoretical calculation of using the Bain strain and lattice invariant shear on (100)011]_f.
Peculiarities of Spatial Spectrum of Scattered Electromagnetic Waves in Anisotropic Inhomogeneous Medium
Vladimir George Gavrilenko;George V. Jandieri;Akira Ishimaru;Vakhtang George Jandieri
PIER B , 2008, DOI: 10.2528/PIERB08032503
Abstract: Features of spatial power spectrum (SPS) of scattered radiation in a randomly inhomogeneous medium with strongly prolated anisotropic inhomogeneities of dielectric permittivity are investigated. In single scattering approximation, it has been shown that a pronounced gap along a direction of prolate inhomogeneities appears in SPS. Features of SPS of multiple scattered waves at oblique illumination of a boundary of randomly-inhomogeneous medium with prolate irregularities have been analytically studied using smooth perturbation method taking into account diffraction effects. Numerical calculations have shown that with an increase of a distance passing by the wave in random media, SPS has a double-peaked shape and a gap substantially increases. Its maximum is slightly changed and the width is broadening. The results have been obtained analytically for the first time and could find extensive practical application in optics and be useful in development of principles of remote sensing of random media.
Effect of Heating Rate on the Morphology of Nano Titanium Dioxide  [PDF]
LIU Bo, KONG Wei, YE Bo, YU Zhong-Ping, WANG Hua, QIAN Guo-Dong, WANG Zhi-Yu
无机材料学报 , 2010, DOI: 10.3724/sp.j.1077.2010.00906
Abstract: Different shapes of nano titanium dioxide including sphere, rod and irregular-shaped polyhedron were prepared by solvothermal process at heating rates of 240 0min, 90 0min, 40 0min and 20 0min using tetrabutyl titanate as Ti source, oleic acid as solvent, dodecylamine as auxiliary agent. TEM, HRTEM and XRD were adopted to characterize the phase composition morphology and phase structure of the final products. The micro-morphology and growth mechanisms of the titanium dioxide nanocrystals prepared at different heating rates were studied based on the TEM, HRTEM and XRD analyses£ The results show that spherical, rod-like, and irregular polyhedral points of titanium dioxide nanocrystals could be synthesized by strictly controlling the heating rate. The growth rate of along the (001) direction of nanocrystal shows a first upward and then downward trend with the decline of the heating rate.
INFLUENCE OF DISPERSIVELY PRECIPITATED PARTICLES ON MARTENSITE MORPHOLOGY IN Fe-Ni-Co-Ti ALLOYS
CUI Lishan Jinzhou Institute of Technology,Jinzheu,ChinaYANG Dazhi LI Guobin ZHU Min Dalian University of Technology,Dahan,China,
CUI Lishan Jinzhou Institute of Technology
,Jinzheu,ChinaYANG Dazhi LI Guobin ZHU Min Dalian University of Technology,Dahan,China

金属学报(英文版) , 1991,
Abstract: The Martensite formed at low temperatures in Fe-Ni-Co-Ti alloys is featured as thin platewhen the size of γ' dispersively precipitated particles was about 20—50 nm.The interface ofmartensite plate is not smooth.If the γ'particles are sized less than 5 nm,the thin platemartensite with thermoelastisity may be found at low temperatures,whi(?) greater than 5 nm,intermittent martensite may occur,and the plate martensite increases both in size and quantitywith the coarsening of the γ particles.The lenticular or butterfly martensite forms at low tem-peratures until the γ' particles are up to 10—5 nm.
INFLUENCE OF P ON FRACTURE MORPHOLOGY OF Cr-Mn-Si STEEL WITH PEARLITE, BAINITE AND MARTENSITE STRUCTURES

by ZHU Xun,LI Lidan,WANG Jucai,

金属学报 , 1986,
Abstract: The influence of P on impact toughness test and SEM observation was investigated on the 30CrMnSiA steel with pearlite, bainite and martensite-bainite mixed structures. Results showed that the cleavage element on the fracture surface increases and the impact toughness decreases as the increasing of P content. The intergranular fracture appeared till P up to 0.020%. An impact toughness sequence of various structures in the steel influenced by P may be arranged as: martensite+bainite>bainite>pearlite.
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