Custom material Property Matrix

To build a custom material Property Matrix, just derive your own material class from the Material one and override the CalcMaterialPropertyMatrix() method to use your custom values.

public class MyMaterial : Material
    {
        public MyMaterial(string name, Color diffuse, double young, double poisson, double yield, double density, double coeffOfThermExp)
            : base(name, diffuse, young, poisson, yield, density, coeffOfThermExp)
        {
        }

        public override void CalcMaterialPropertyMatrix(int numberOfDimensions, elementType elType)
        {

            double[,] dMat = null;

            switch (numberOfDimensions)
            {
                case 2:
                    switch (elType)
                    {
                        case elementType.PlaneStress:

                            dMat = new double[3, 3];

                            dMat[0, 0] = 1;
                            dMat[1, 1] = 1;
                            dMat[0, 1] = 1;
                            dMat[1, 0] = 1;
                            dMat[2, 2] = 1;

                            break;

                        case elementType.PlaneStrain:

                            dMat = new double[3, 3];

                            dMat[0, 0] = 1;
                            dMat[1, 1] = 1;
                            dMat[0, 1] = 1;
                            dMat[1, 0] = 1;
                            dMat[2, 2] = 1;

                            break;

                        case elementType.Axisymmetric:

                            dMat = new double[4, 4];

                            dMat[0, 0] = 1;
                            dMat[1, 0] = 1;
                            dMat[2, 0] = 1;
                            dMat[0, 1] = 1;
                            dMat[1, 1] = 1;
                            dMat[2, 1] = 1;
                            dMat[0, 2] = 1;
                            dMat[1, 2] = 1;
                            dMat[2, 2] = 1;
                            dMat[3, 3] = 1;

                            break;

                    }

                    break;

                case 3:

                    dMat = new double[6, 6];

                    dMat[0, 0] = 1;
                    dMat[1, 1] = 1;
                    dMat[2, 2] = 1;
                    dMat[3, 3] = 1;
                    dMat[4, 4] = 1;
                    dMat[5, 5] = 1;
                    dMat[0, 1] = 1;
                    dMat[1, 0] = 1;
                    dMat[0, 2] = 1;
                    dMat[2, 0] = 1;
                    dMat[1, 2] = 1;
                    dMat[2, 1] = 1;

                    break;
            }

            D = dMat;
        }
    }