Issue 52

M. Fouzia et alii, Frattura ed Integrità Strutturale, 52 (2020) 281-298; DOI: 10.3221/IGF-ESIS.52.22

The parameters of the hybrid assembly are given in Tab. 6. In this design of experiment optimization two factors are considered namely the thickness of the adhesive e a and the width of the subtracts w. We have two factors with two levels which give 2 2 experiments. Tab. 7 shows the values of the factors and the corresponding response value of the displacement.

Thickness of the adhesive

N0 of Experiment

Width of the substrates

Displacement Δl

01

0.3

38

4.981

02

0.3

100

4.93

03

0.7

38

5.501

04

0.7

100

5.44

Table 7: Values of the factors and the response

Coded values of the factors and interactions are given in the matrix of experiments Tab. 8.

Factors

ea

Width

ea* width

Displacement

ea

1

0

0

0.994094

width

0

1

0

-0.108096

ea* width

0

0

1

-0.00965127

Displacement

0.994094

-0.108096

-0.00965127

1

Table 8: Matrix of experiments (coded values).

The predicted model is a first order model with respect to each factor expressed as:

0 1 1 2 2 12 1 2 y a a x a x a x x = + + +

(20)

where: y is the response corresponding to the displacement x i represents the level given to factor i. a 0 is the average value at the center of the design study plan.

a 1 is the coefficient of factor 1. a 2 is the coefficient of factor 2. a 12 is the interaction of the two factors 1 and 2. The coefficients of the model are obtained using the design of experiments software MOODE.

Coefficients

Value

average a 0

5.213

a 1 coefficient ea

0.297335

a 2 coefficient the width of substrates

-0.0323316

a 12 interaction ea* width

-0.00333319

Table 9: the coefficient of the model

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