不同力学边界下变物性梯度功能材料板稳态热应力

Steady thermal stresses of functionally gradient material plate with temperature-dependent properties under differently mechanical boundary

用非线性有限元法和辛普生法分析了由ZrO2和Ti-6Al-4V组成的变物性梯度功能材料板在不同力学边界条件下的稳态热应力问题.结果表明:当无限长板只能伸长、不能弯曲时,板内稳态拉应力最大,比无限自由长板时板内最大拉应力增大6.1倍;当无限长板伸长、弯曲受限时,板内的压应力最大,比无限自由长板时板内最大压应力增大14.9倍;考虑变物性的最大拉应力比常物性减小48.9%,最大压应力比常物性减小39.6%;此外,材料组分形状系数M、对流换热系数和孔隙度的变化对不同力学边界条件下该变物性材料板稳态热应力场的影响显著.此结果为该材料的设计和应用提供了准确的理论计算依据.图4,表1,参8.

The steady thermal stresses in functionally gradient material(ZrO_2 and Ti-6Al-4V)(FGM) plate with tempera-ture-dependent properties under differently mechanical boundary are analyzed by the nonlinear finite element method and the Sinpson method. The numerical results show that the tensile stresses in the plate are maximum and the maximum tensile stresses are 8.6 times as large as those in the infinitely long traction-free plate when the bending of the plate is only limited.It is also found that the compressive stresses are maximum and the maximum compressive stresses in the plate are 15.9 times as large as those in the infinitely long traction-free plate when the elongation and the bending of the plate are limited.The maximum compressive stress with temperature-dependent properties is 39.6% less than that of the FGMs with constant material properties,and the maximum tensile stress is 48.9% less than that.In addition,the stress distributions are substantially changed with the change of the parameter M of the material composition and the porosity P and the convective heat transfer coefficients.The results of this paper provide the foundations of theory calculation for the design and application of the FGMs.4figs.,1tab.,8refs.