The code example below shows how to define a material model in Python using AML Python Module. Run this code in anspython.

import ansys.mapdl.materials.aml as aml 
import numpy as np

# Material Definition
mymaterial = aml.material(1)
mylist = [10,-1,1e-3]
myfld = dict()
myfld['temp'] = 0.0
mymaterial.add_table("hype","moon",myfld,mylist)
mymaterial.print("hype","moon")


# Calling the driver
disp = 0.1
# Assuming an example uniaxial stress state l2 can be calculated as sqrt(1/l1)
l1 = 1+disp
l2 = (1/(l1))**0.5
#solution parameters
solutiondata = dict()
solutiondata['time'] = 101.0
solutiondata['dtime'] = 0.0 
defgrad_t = [1,0,0,0,1,0,0,0,1]
defgrad = [l1,0,0,0,l2,0,0,0,l2]
outputstress = []
jacobian = []
mymaterial.initialize()
[outputstress,jacobian,status] = mymaterial.evaluate(solutiondata,defgrad_t,defgrad)
print("Stress is ", outputstress)
jacobmatrix = np.array(jacobian)
jacobmatrix = jacobmatrix.reshape((6,6))
print('Material Algorithms Converged Status is', status['converged'])
print("Jacobian :")
print(jacobmatrix)