A novel approach is proposed in determining dy- namic fracture toughness （DFT） of high strength steel, using the split Hopkinson tension bar （SHTB） apparatus, com- bined with a hybrid experimental-numerical method...A novel approach is proposed in determining dy- namic fracture toughness （DFT） of high strength steel, using the split Hopkinson tension bar （SHTB） apparatus, com- bined with a hybrid experimental-numerical method. The center-cracked tension specimen is connected between the bars with a specially designed fixture device. The fracture initiation time is measured by the strain gage method, and dynamic stress intensity factors （DSIF） are obtained with the aid of 3D finite element analysis （FEA）. In this approach, the dimensions of the specimen are not restricted by the connec- tion strength or the stress-state equilibrium conditions, and hence plane strain state can be attained conveniently at the crack tip. Through comparison between the obtained results and those in open publication, it is concluded that the ex- perimental data are valid, and the method proposed here is reliable. The validity of the obtained DFT is checked with the ASTM criteria, and fracture surfaces are examined at the end of paper.展开更多
This paper experimentally studies the tensile deformation behavior of poly- carbonate （PC）, acrylonitrile-butadiene-styrene （ABS）, and PC/ABS blends （with the blending ratios of PC to ABS being 80：20, 60：40, 50...This paper experimentally studies the tensile deformation behavior of poly- carbonate （PC）, acrylonitrile-butadiene-styrene （ABS）, and PC/ABS blends （with the blending ratios of PC to ABS being 80：20, 60：40, 50：50, and 40：60） from low to high strain rates. Using the universal MTS-810 machine and the split Hopkinson tension bar （SHTB） testing system, the quasi-static and impact tension tests are carried out at the room temperature. The curves of the true stress and the true strain are obtained. The deformation behaviors of PC, ABS, and PC/ABS blends are characterized in detail. The linear relationship between the strain rate and the yielding stress is given.展开更多
基金supported by the 111 Project (B07050)the National Natural Science Foundation of China (10932008)
文摘A novel approach is proposed in determining dy- namic fracture toughness （DFT） of high strength steel, using the split Hopkinson tension bar （SHTB） apparatus, com- bined with a hybrid experimental-numerical method. The center-cracked tension specimen is connected between the bars with a specially designed fixture device. The fracture initiation time is measured by the strain gage method, and dynamic stress intensity factors （DSIF） are obtained with the aid of 3D finite element analysis （FEA）. In this approach, the dimensions of the specimen are not restricted by the connec- tion strength or the stress-state equilibrium conditions, and hence plane strain state can be attained conveniently at the crack tip. Through comparison between the obtained results and those in open publication, it is concluded that the ex- perimental data are valid, and the method proposed here is reliable. The validity of the obtained DFT is checked with the ASTM criteria, and fracture surfaces are examined at the end of paper.
基金supported by the National Natural Science Foundation of China (No. 11142004)the Shang-hai Leading Academic Discipline Project (No. S30106)the Innovative Foundation of Shanghai University
文摘This paper experimentally studies the tensile deformation behavior of poly- carbonate （PC）, acrylonitrile-butadiene-styrene （ABS）, and PC/ABS blends （with the blending ratios of PC to ABS being 80：20, 60：40, 50：50, and 40：60） from low to high strain rates. Using the universal MTS-810 machine and the split Hopkinson tension bar （SHTB） testing system, the quasi-static and impact tension tests are carried out at the room temperature. The curves of the true stress and the true strain are obtained. The deformation behaviors of PC, ABS, and PC/ABS blends are characterized in detail. The linear relationship between the strain rate and the yielding stress is given.
