复合材料高温失效vumat代码
时间: 2023-07-09 13:36:07 浏览: 60
复合材料在高温环境下容易发生热失效,导致材料的力学性能下降甚至失效。为了预测复合材料在高温下的失效行为,可以采用 VUMAT 子程序实现材料模型的编写和求解。以下是一个简单的复合材料高温失效的 VUMAT 代码示例:
```
SUBROUTINE VUMAT(STRESS,STATEV,DDSDDE,SSE,SPD,SCD,
& RVECT,TIME,DTIME,TEMP,DTEMP,PREDEF,DPRED,
& CMNAME,NDI,NSHR,NTENS,NSTATV,PROPS,NPROPS,
& COORDS,DROT,PNEWDT,CELENT,DFGRD0,DFGRD1,
& NOEL,NPT,layer_thickness,thermal_expansion_coeff)
IMPLICIT DOUBLE PRECISION (A-H,O-Z)
DIMENSION STRESS(NTENS),STATEV(NSTATV),DDSDDE(NTENS,NTENS),
& RVECT(3),SPD(1),SCD(1),PROPS(NPROPS),COORDS(3),
& DROT(3,3),CELENT(3),DFGRD0(3,3),DFGRD1(3,3)
! Material properties
DOUBLE PRECISION, PARAMETER :: E1 = PROPS(1), E2 = PROPS(2), G12 = PROPS(3)
DOUBLE PRECISION, PARAMETER :: nu12 = PROPS(4), alpha = PROPS(5)
! Thermal properties
DOUBLE PRECISION :: T0, T
DOUBLE PRECISION, PARAMETER :: Tmelt = PROPS(6)
DOUBLE PRECISION, PARAMETER :: beta = PROPS(7)
! Strain and stress components
DOUBLE PRECISION :: epsilon1, epsilon2, gamma12
DOUBLE PRECISION :: sigma1, sigma2, tau12
! Stress and strain tensors
DIMENSION STRESS(NTENS), STRAIN(NTENS,NTENS), E(NTENS,NTENS), S(NTENS,NTENS), Q(NTENS,NTENS)
! Calculate current temperature
T0 = TEMP
T = T0 + alpha * DTEMP
! Calculate thermal strain tensor
STRAIN(1,1) = alpha * (T - T0)
STRAIN(2,2) = STRAIN(1,1)
STRAIN(3,3) = 0.0d0
! Calculate strain tensor due to deformation
STRAIN(1,1) = STRAIN(1,1) + DEFG(1,1) - 1.0d0
STRAIN(2,2) = STRAIN(2,2) + DEFG(2,2) - 1.0d0
STRAIN(3,3) = STRAIN(3,3) + DEFG(3,3) - 1.0d0
STRAIN(1,2) = DEFG(1,2)
STRAIN(2,1) = DEFG(2,1)
! Calculate stress tensor due to deformation and temperature
E(1,1) = E1 / (1.0d0 - nu12 * nu12)
E(2,2) = E2 / (1.0d0 - nu12 * nu12)
E(1,2) = nu12 * E2 / (1.0d0 - nu12 * nu12)
E(2,1) = E(1,2)
E(3,3) = G12
E(1,3) = 0.0d0
E(3,1) = E(1,3)
E(2,3) = 0.0d0
E(3,2) = E(2,3)
S = MATMUL(E,STRAIN)
Q = S / (1.0d0 + beta * (T - Tmelt))
! Calculate stress components
sigma1 = Q(1,1)
sigma2 = Q(2,2)
tau12 = Q(1,2)
! Check for high temperature failure
IF (T > Tmelt) THEN
IF (ABS(tau12) > sigma1 * G12 / E1) THEN
sigma1 = 0.0d0
sigma2 = 0.0d0
tau12 = 0.0d0
STATEV(1) = 1.0d0
END IF
END IF
! Update stress tensor
STRESS(1) = sigma1
STRESS(2) = sigma2
STRESS(3) = 0.0d0
STRESS(4) = tau12
STRESS(5) = 0.0d0
STRESS(6) = 0.0d0
! Update state variables
STATEV(2) = T
RETURN
END SUBROUTINE VUMAT
```
这个 VUMAT 子程序实现了复合材料在高温下的失效判断,当复合材料的剪切应力超过其破坏强度时,就认为材料已经失效,并将其应力设置为零。需要注意的是,这个示例代码仅供参考,实际应用中需要根据具体的材料特性和失效机理进行相应的调整和优化。