虞忠良
,
李守新
,
刘羽寅
,
雷家峰
材料研究学报
采用拉压对称的机械应变控制, 研究了Ti-6-22-22合金在200~400℃和200~520℃两个温度范围的热机械疲劳(TMF)行为. 结果表明,
在200~400℃内, 同相和反相热机械疲劳寿命均高于400℃等温疲劳寿命; 在200~520℃范围, 反相热机械疲劳寿命明显低于520℃等温疲劳寿命.
在两个温度范围内, 热机械疲劳的循环应力都与相应等温疲劳的循环应力响应有关. 纵向剖面金相观察表明, 520℃时等温疲劳表面的裂纹更长.
循环温度范围扩大导致环境破坏作用增强是热机械疲劳具有明显破坏作用的原因.
关键词:
金属材料
,
Ti-6-22-22
,
thermo-mechanical fatigue
,
isothermal fatigue
H.J.Shi
金属学报(英文版)
A Voronoi cell element, formulated with creep, thermal and plastic strain was applied for investigation of thermo-mechanical fatigue behavior for particulate reinforced composites. Under the in-phase fatigue loading, the maximum of tensile deformation at the maximum given loading are larger than that at the same maximum under the out-phase fatigue. The stiffness decreases nonlinearly with the increasing of the phase angle, which results in increasing of the area of fatigue loop curve and the decrease in fatigue life. The spatially centralizing of inclusions results in decreasing of the plastic strain amplitude and the area of fatigue loop curve, which will also reduce the consumption of single-circle plastic strain energy and prolong the fatigue life.
关键词:
thermo-mechanical fatigue
,
null
,
null
