Influence of Different Material of Penetrator on Micro-Hardness of Steel Target

Contrast ballistic tests were carried out on 93W alloy and W fiber reinforced Zr-based bulk metallic glass composite. The influence of penetrator material on micro-hardness around target crater was studied using microstructure observation and micro-hardness test. The results show that adiabatic shear band appears in both targets after severe plastic deformation of impact. The effect of composite on micro-hardness of target is greater than that of W alloy, and the thickness with high micro-hardness around target crater formed by composite penetrator is 2.5 times than that by W alloy penetrator.

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Evolution of Adiabatic Shear Band in Ultra-Fine-Grained Iron under Dynamic Shear Loading

Materials Science Forum ◽

10.4028/www.scientific.net/msf.667-669.761 ◽

2010 ◽

Vol 667-669 ◽

pp. 761-765 ◽

Cited By ~ 1

Author(s):

Fu Ping Yuan ◽

Xiao Lei Wu

Keyword(s):

Grain Size ◽

Shear Band ◽

Adiabatic Shear Band ◽

Shear Loading ◽

Electron Back Scatter Diffraction ◽

Adiabatic Shear ◽

Dynamic Shear ◽

Micro Hardness ◽

Fine Grained ◽

Angular Pressing

Ultra-fine-grained (UFG)/Nanocrystalline (NC) materials usually show reduced strain hardening and limited ductility due to formation of adiabatic shear band (ASB) under dynamic loading. In the present study, evolution of ASB in UFG Fe under dynamic shear loading was investigated. The UFG Fe was processed by equal-channel angular pressing (ECAP) via route Bc. After 6 passes, the grain size of UFG Fe reaches ~ 600 nm, as confirmed by means of Electron Back Scatter Diffraction (EBSD). Examination of micro-hardness and grain size of UFG Fe as a function of post-ECAP annealing temperature shows a transition from recovery to recrystallization at 500 0C. The high-strain-rate response of UFG Fe was characterized by hat-shaped specimen set-ups in Hopkinson bar experiments. The characteristics of ASB as a function of shear displacement, such as thickness of shear band and micro-hardness inside the shear band, were examined by SEM and Vickers micro-indentation respectively.

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Chip Formation Characteristics in High-Speed Machining of Hardened AISI1045 Steel

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.565.484 ◽

2012 ◽

Vol 565 ◽

pp. 484-489

Author(s):

Bing Wang ◽

Zhan Qiang Liu ◽

Qi Biao Yang

Keyword(s):

Shear Band ◽

Chip Formation ◽

High Speed ◽

Adiabatic Shear Band ◽

Cutting Speed ◽

Adiabatic Shear ◽

High Speed Machining ◽

Micro Hardness ◽

Serrated Chip ◽

Aisi1045 Steel

Analyzing mechanism of the chip formation is a significant way to understand the metal cutting process better. The characterization of serrated chip formation in high speed machining of hardened AISI1045 steel is investigated with the aid of optical microscopy and micro-hardness measurement in this paper. The chip morphology evolving from continuous one to serrated one with the cutting speed increasing from 100-1500m/min is observed. Compared with the continuous chip pattern, serrated chip has its particular characterization parameters. The characteristics of serration degree and the segmentation frequency of the serrated chip are presented. The micro-hardness at the adiabatic shear band of serrated chip is then measured. The results show that the serration degree and segmentation frequency of serrated chip have a tendency of enhancement with the cutting speed increasing. The micro-hardness along the adiabatic shear band increases with the cutting speed increasing due to severe strain hardening. With a critical speed at about 100-200m/min, micro-hardness decreases from the tool-chip interface to the free surface of the chip.

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The Formation of Adiabatic Shear Band and Analysis of its Characteristics in the Process of Penetration

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.472-475.2846 ◽

2012 ◽

Vol 472-475 ◽

pp. 2846-2849

Author(s):

Jin Quan Li ◽

Sheng Xu Wang

Keyword(s):

Plastic Deformation ◽

Shear Band ◽

Steel Plate ◽

Adiabatic Shear Band ◽

Shear Bands ◽

Adiabatic Shear ◽

Stress And Strain ◽

Adiabatic Shear Bands ◽

Micro Cracks ◽

Armor Steel

The characteristics and causes of the formation of adiabatic shear bands (ASB) in 30CrMnMo armor steel plate are analyzed by shooting 93W projectiles. The results show that adiabatic shear bands do not occur in the initial stages of the opening-crater and plugging. Adiabatic shear bands distributed sparsely appear in the stable penetrating phase because of the necessary strain volume. Adiabatic shear bands are formed along main shear stress lines at an angle of about 450 in relation to the penetrating direction. These are approximately consistent with the direction of the plastic deformation slip line. The non-homogenous deformation and centralizing of stress and strain inside the adiabatic shear band causes micro-cracks and micro-bores during cooling of the plate.

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