摘要
分别采用三点弯曲SE(B)与紧凑拉伸C(T)试样,通过-20℃的低温裂纹尖端张开位移CTOD断裂韧性试验及疲劳裂纹扩展速率da/dN试验,研究了S355N及S355N-Z25结构钢的裂纹启裂与扩展的抗力。研究结果表明:S355N钢抵抗裂纹启裂及前期扩展的能力比S355N-Z25钢强,但前者抵抗裂纹后期扩展的能力比后者弱;当应力强度因子范围ΔK小于34.3MPa.槡m时,S355N钢的疲劳抗力比S355N-Z25钢弱,当ΔK等于34.3MPa.槡m时,两者具有相同的疲劳抗力,当ΔK大于34.3MPa.槡m时,前者的疲劳抗力比后者强。研究结果对两种钢板在工程上应用及结构的安全评定提供了参考。
Adopting three-point bend SE（B） and compact tensile C（T） specimen,through crack-tip opening displacement CTOD fracture toughness test at-20℃ and fatigue crack propagation rate da/dN test,resistance to crack initiation and propagation of S355N and S355N-Z25 structural steel plates were studied.The results manifested that S355N steel is stronger in resistance to crack initiation and prophase growth than S355N-Z25 steel,but is weaker to crack anaphase propagating.When stress strength factor ΔK is less than 34.3MPa·m,S355N steel has less fatigue resistance than S355N-Z25 steel.When ΔK equals 34.3MPa·m,both have the same fatigue resistance.When ΔK is more than 34.3MPa·m,the former has stronger fatigue resistance than the latter.These information may provide reference for the steels as used in safety-assessing of engineering structure.
出处
《材料开发与应用》
CAS
2011年第5期42-44,48,共4页
Development and Application of Materials
