**4. Results and discussions**

**Table 2** displays the decision matrix for the pure aluminum graphene nanoplatelets (GNP's) composites, which contains five alternatives and five parameters (1 & 2). The entropy method was used to calculate the objective weights, which are described in **Table 3**. MATLAB R2020a software was used to create a programme that used the formulae for the methods (EDAS and VIKOR) to determine performance measures. The entropy methods are used to measure the weights of different parameters such as mass, percentage elongation, tensile strength (TS), hardness, and impact strength (IS). The material that is used for fuselage construction is of lightweight and good strength and is more corrosion resistant. An attempt was made by developing an alternative material to serve the purpose.

#### **4.1 Evaluation based on distance from average solution (EDAS) method**

**Table 1** decision matrix displays the average solution (AVj) determined using Eq. (3). Eqs. (4) and (5) were used to quantify positive and negative distances based


#### **Table 2.**

*Decision matrix.*


*Selection of Optimal Material from Stir Cast Aluminum Graphene Nano Platelets… DOI: http://dx.doi.org/10.5772/intechopen.100478*


**Table 4.**

*(PDA) positive distance from average.*


#### **Table 5.**

*(NDA) negative distance from average.*


**Table 6.**

*Normalized positive and negative weighted sums, appraisal scores, and rank of alternatives.*

on the types of beneficial and non-beneficial parameters mentioned in **Tables 4** and **5**. Eqs. (6) and (7) are used to measure the positive and negative weighted sums (7). Eqs. (8) and (9) are used to measure the normalized positive and negative weighted sums (9). Eq. (10) is used to measure the final assessment score (ASi) for all alternatives, as shown in **Table 6**. 5-1-2-3-4 is the ranking of alternative composite materials. The best composite for the fuselage in aircraft applications is pure aluminum reinforced with 0.5wt% GNP, though pure aluminum is the least favored.

## **4.2 VIse Kriterijumska OptimizacijaKompromisno Resenje (VIKOR) method**

The related utility and regret measures, as well as Qi values for the five alternative composite materials and the parameters, are determined using Eqs. (13)–(17), as shown in **Table 7** (taking N = 0.5). **Table 8** shows the best and worst values for the beneficial and non-beneficial criteria measured using Eqs. (11) and (12). The ranks of alternative composite materials are 5-1-2-3-4. The first place winner is pure


**Table 7.**

*Utility and regret measure values and rank of the alternatives.*


**Table 8.** *Best and worst of criterion.*

aluminum reinforced with 0.5 wt% GNPs. VIKOR is more beneficial compared to EDAS, though the results are comparatively same. All the expressions were objective with respective to VIKOR to EDAS.
