Ductility loss in Hydrogen-charged Ductile Cast Iron
Hydrogen-induced ductility loss in ductile cast iron (DCI) was studied by conducting a series of tensile tests with three different crosshead speeds.By utilizing the thermal desorption spectroscopy and the hydrogen microprint technique,it was found that most of the solute hydrogen was diffusive and mainly segregated at the graphite,graphite/matrix interface zone and the cementite of pearlite in the matrix.The fracture process of the non-charged specimen was dominated by the ductile dimple fracture,whereas that of the hydrogen-charged specimen became less ductile by accompanying the interconnecting cracks between the adjacent graphite nodules.Inside of the hydrogen-charged specimen,the interspaces generated by the interfacial debonding between graphite and matrix are filled with hydrogen gas in the early stage of the fracture process.In the subsequent fracture process,such a local hydrogen gas atmosphere coupled with a stress-induced diffusion attracts hydrogen to the crack tip,which results in a time-dependent ductility loss.
Hydrogen Hydrogen embrittlement Ductile cast iron Ductility loss
Hisao Matsunaga Teruki Usuda Keiji Yanase Masahiro Endo
Department of Mechanical Engineering,Kyushu University,Fukuoka 819-0395,Japan;International Institut Graduate School of Fukuoka University,Fukuoka 814-0180,Japan Institute of Materials Science and Technology,Fukuoka University,Fukuoka 814-0180,Japan;Department o
国际会议
北京
英文
1-10
2013-06-16（万方平台首次上网日期，不代表论文的发表时间）