| The present works were financial supported by the National Nature Science Foundation of China (Project No. 50471059) and the Ph.D. Programs Foundation of Ministry of Education of China (Project No. 20020533015). The major work were listed as follows.It was the first time that the microtexture in adiabatic shear band (ASB) generated by adiabatic shearing deformation was investigated by means of scanning electron microscopy/electron back-scattered diffraction (SEM/EBSD). The microstructure in ASB was directly observed with transmission electron microscopy (TEM). The results indicated that highly elongated subgrains and fine equiaxed grains with low dislocation density were observed in the ASB, and recrystallization microtextures were formed within ASB, and the grain boundaries within ASB were geometrically necessary boundaries (GNBs) with high-angles. Finite element computations were performed to obtain the effective strain and temperature distributions within the ASB under the measured boundary conditions. The result indicated that the temperature in the ASBs was estimated to be about 889.1～953.9K (～0.48Tm). Combined with the analysis of the microstructure as well as the microtexture and the results of computer simulation, a subgrain directional rotation dynamic recrystallization model was proposed, at the same time, the kinetic of recrystallization was calculated. The microstructure evolution within ASB was preceded as follows: At the deformation stage, elongated dislocations and subgrains formed in the shear band, and elongated subgrains broke up into smaller subgrains' units, and the fine recrystallized grains were generated finally by the rotation of subgrains' boundaries; There was the formation of the recrystallization textures which were generated by the unstable shear textures' directional nucleation at the above deformation stage; The fine equiaxed grains in the ASB were not obvious growed up at the cooling stage.Dynamic loading was carried on the hat-shaped specimens of the new titanium alloy TC16 by Split Hopkinson Pressure Bar (SHPB) technique. Johnson-Cook constitutive equation was selected to describe the dynamic behavior of the TC16 alloy, and the parameters of the equation were obtained by the nonlinear least squares procedure, and the dynamic constitutive equation of TC16 alloy was described. The microstructure and the phase transformation of ASB produced in TC16 alloy were investigated by means of OM, microhardness test, SEM and TEM. Combined the dynamic response data and the adiabatic temperature rise calculation, the thermal-mechanics evolution during the formation of ASB was obtained. The phase transformation and the microstructure evolution process within ASB in TC16 alloy were explained.It was the first time that collective behavior of large assemblages of ASBs on the titanium side in the titanium/mild steel explosive cladding plate interface was quantified investigated. The change of length, spacing and trace of ASBs initiating at the wavy interface was characterized as periodic and organized. The models those to calculate and to describe the ASBs spacing and trajectory in the explosive cladding plate were proposed. The distribution of ASBs on the titanium side was described by the trajectory model combined with the initial spacing of ASBs. The shear band propagation speed was calculated by use of the trajectory model of ASBs. The effects of applied loads and the materials parameters on the shear band spacing, trajectory, distribution and propagation speed were delineated.The ASBs produced in the TA2 tube under external explosive loading were investigated by means of the metal tube pressure explosive experimental equipment. Experimental results indicated that the ASBs were initiated at the internal surface of the tube and the cracks were formed along the shear bands. The tip of a shear band propagated along the surfaces of the maximum shear stress. The most of ASBs in the cross-section of the specimen rotated counterclockwise in the same direction. The special patterns of ASBs such as the bifurcation, influx, crossing and "N"-shape were observed. The developed shear bands were the preferred sites for nucleation, growth and coalescence of micro-voids. The formation of ASBs in the TA2 tube on application of external explosive loading and the micro-void evolution within the shear bands were described.
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