# Microstructure, Process Optimization, and Strength Response Modelling of Green-Aluminium-6061 Composite as Automobile Material

^{1}

^{2}

^{3}

^{4}

^{5}

^{6}

^{7}

^{*}

## Abstract

**:**

## 1. Introduction

_{2}, TiO

_{2}, Al

_{2}O

_{3}, TiN, B

_{4}C, and many more. These ceramic particles have been employed extensively in many studies and have brought about tremendous outcomes [5,6]. Environmental wastes may include agro-waste and industrial wastes [7,8,9,10].

## 2. Experimental Procedure

#### 2.1. Design of Experiment

#### Response Surface Method (RSM)

_{1}, X

_{2}, and X

_{3}are the independent experimental variables in place of PKA dosage, RHA proportion, and stirring temperature. Equally, ${a}_{0},{a}_{1},{a}_{2},{a}_{3},{a}_{12},{a}_{13},{a}_{23},{a}_{11},{a}_{22}$ and ${a}_{33}$ are coefficient of terms. The model expresses the responses as a function of the independent variables. In this study, the responses are tensile, compressive, and flexural strengths; and tensile and compressive moduli.

#### 2.2. Material

#### 2.3. Composite Development

^{3}/s and allowed to cool to room temperature.

#### 2.4. Mechanical and Morphological Characterization

#### 2.4.1. Tensile Properties

^{−3}/s and a cross speed of 3 mm/min.

#### 2.4.2. Compressive Properties

^{−2}/s rate until fracture using the universal testing machine. Compressive strength was obtained as the ratio of fracture load to cross-sectional area.

#### 2.4.3. Flexural Properties

#### 2.4.4. Morphological, Elemental, and Phase Characterization

## 3. Results

#### 3.1. Properties of Input Materials

_{2}O

_{3}, Fe

_{2}O

_{3}, MnO

_{2}, and CaO are other compounds present.

_{2}is the most occurring phase, attaining positions of 19.5, 24.7, 32.8, 37.6, 42.5, 47.1, and 50.1 degrees, hence, agreeing with the observation of Farooque et al. [49]. The results are consistent with Table 4, which shows a SiO

_{2}proportion of 90.21% in RHA. Significantly, the strengthening of an aluminium base matrix with RHA has been on account of the rich silica content, which serves as a substitute for synthetic silica. By the chemical composition of variables, they are fit for the reinforcement of Al-6061.

#### 3.2. Microstructural and Phase Characterization

_{2}, Fe, and the Al phase were recognized in the specimens. The highest peak in aluminium is typical of aluminium-based alloys. The presence of SiO

_{2}is due to the reinforcement of PKA and RHA. Fe is also present owing to intrinsic Fe in Al6061 as well as assimilated steel particles included in the melt. Figure 3c,d shows XRD data for specimens cast at 800 °C and prepared with 2% PKA/6% RHA and 6% PKA/2% RHA, respectively. From the XRD plot, there is a higher presence of silica, as depicted by the higher peak of the silica phase. The phases present in specimens prepared at 900 °C with 6% PKA/4% RHA and 4% PKA/6% RHA, respectively, are depicted in Figure 3e,f. As featured in the results, intermetallic phases of Mg

_{2}Si, Al

_{5}FeSi, and Al

_{15}Si

_{2}(FeMn) are revealed. The implication of this is that 900 °C features the existence of intermetallic phases attributed to high-temperature reactions.

_{2}and Al, with no intermetallic phase present.

_{2}Si, Al

_{5}FeSi, and Al

_{15}Si

_{2}(FeMn) are the phases identified, which correlate to the literature references [59,60,61]. The phases are also visible in the XRD (Figure 3) for a specimen of formulation 4% PKA and 6% RHA cast at 900 °C.

_{2}Si, Al

_{5}FeSi, and Al

_{5}S

_{12}(FeMn) intermetallic phases, respectively. The elemental maps in the specimen are featured in Figure 6g–j. Due to the fact that it is the basic element, Al dominated the element distribution within the matrix (Figure 6g). It is also among the intermetallic elements, according to the EDS elemental composition of the discovered spots. Figure 6h depicts the Si distribution, while Figure 6i and Figure 7j depict the Fe and Mn elemental distributions, respectively.

#### 3.3. Response Surface Analysis

#### 3.3.1. Analysis of Variance (ANOVA) and Mathematical Models

^{2}, (RHA vs. RHA) B

^{2}, and (Temperature vs. Temperature) C

^{2}are determined to have a consequential contribution to tensile strength, while other interactions have an insignificant effect on the response (since the p-value is less than 0.05). Only changes in interaction C

^{2}have a significant effect on tensile modulus, whereas other interactions have no discernible effect. The p-value for the model for each of tensile strength (Table 7a) and elastic modulus (Table 7b) is less than 0.05, indicating that the models (Equations (1) and (2)) are significant. This is further corroborated by the lack of fit, where the p-value is greater than 0.05 in each case. Hence, the models have a high degree of fitness. The coefficient of correlation R

^{2}for the model is 0.9788 and 0.9751 for TS and TM, respectively, corroborating their high degree of fitness. In that case, 97.88% of the data is explained by the model for tensile strength, whereas 99.51% for that of elastic modulus. Accordingly, the models have a good correlation with the fitted data. Since the disparity between R

^{2}(adj) and R

^{2}(pred) for TS and TM is not above 0.2, there exists an agreement between the two parameters and the models are fit for response prediction.

^{2}− 8.7500 B

^{2}− 0.0038 C

^{2}− 2535.2500

^{2}+ 0.1563 B

^{2}− 0.0025 C

^{2}− 1495.5000

^{2}− 8.7500 B

^{2}− 0.0038 C

^{2}− 2535.2500

^{2}+ 0.1563 B

^{2}− 1495.5000

^{2}are observed to show a consequential effect on the two response parameters; whereas, the other interactions are portrayed to have a marginal impact on the responses (since the p-value is less than 0.05).

^{2}for the model is 0.9826 and 0.9865 for CS and CM, respectively, corroborating their high degree of fitness. Inference: 98.26% of the data is explained by the model for compressive strength, while 98.65% for that of compressive modulus. Accordingly, the relationship has a good correlation with the fitted data. Since the disparity between R

^{2}(adj) and R

^{2}(pred) for CS and CM is not above 0.2, there exists a synergy between the two parameters and the models are fit for response prediction.

^{2}− 0.3125 B

^{2}− 0.0025 C

^{2}− 1433.5000

^{2}− 0.1875 B

^{2}− 0.0018 C

^{2}− 1138.5000

^{2}− 1433.5000

^{2}− 1138.5000

^{2}, B

^{2}, and C

^{2}also contributed significantly to the response. Meanwhile, other cross-interactions between the factors had inconsequential contributions to the response (since p-v is less than 0.05). The p-value for the model of flexural strength is denoted to be less than 0.05, signifying a significant model (Equations (1) and (6)). Furthermore, the significance of the model is evinced by the lack of a p-value greater than 0.05. By implication, the model has a high degree of fitness. The coefficient of correlation R

^{2}for the model is 0.9866, showing there exists a good correlation between the response data and the model. By deduction, 98.66% is explained by the model for flexural strength response. Since the disparity between R

^{2}(adj) and R

^{2}(pred) is less than 0.2, there is therefore a good agreement between the terms, affirming a statistically fit model.

^{2}− 6.1563 B

^{2}− 0.0040 C

^{2}− 2511.5000

#### 3.3.2. Diagnostic Plot

^{2}values, which are greater than 0.95.

^{2}(prediction) for the plots is valued above 0.9, a case in which the prediction of the model may have less than a 10% deviation. Tensile modulus, compressive strength, and compressive modulus have an R

^{2}(pred.) greater than 0.95, depicting a very good model statistically fit for response with less than 5% error.

#### 3.4. Surface and Contour Plots

#### 3.4.1. Tensile Strength

#### 3.4.2. Tensile Modulus

#### 3.4.3. Compressive Strength

#### 3.4.4. Compressive Modulus

#### 3.4.5. Flexural Strength

#### 3.5. Process Mapping

#### 3.6. Optimization and Result Validation

#### 3.7. Morphology of the Optimized Specimen

## 4. Conclusions

- i.
- The microstructural images displayed features that reflected the relationship between the properties of the composite and the microstructure. Reinforcing particles were dispersed at 700 °C and 800 °C even as 900 °C showed some intermetallics due to high-temperature reaction.
- ii.
- The ANOVA results demonstrated that the independent variables of the study (PKA, RHA, and stirring temperature) have appreciable effects on the responses.
- iii.
- PKA and RHA at 2–4% contributed to increased tensile and flexural strengths when compared with the pure Al6061, while 4–6% of the additives decreased strength values.
- iv.
- Tensile and compressive modulus and compressive strength were greatly improved between 2 and 6% of both particles.
- v.
- The surface and contour plots showed the responses were dependent on the mode of the interplay between the variables.
- vi.
- The optimum mix was obtained as 4.81% PKA, 5.41% RHA, and 803 °C and the predicted values of responses at that condition were 328.616 MPa, 105.011 GPa, 311.553 MPa, 94.4965 GPa, and 328.566 MPa for tensile strength, tensile modulus, compressive strength, compressive modulus, and flexural strength, respectively.
- vii.
- Confirmation results for the responses are 318 MPa, 99 GPa, 324 MPa, 102 GPa, and 334 MPa for respective responses. The deviation for each response is less than 5%, thereby validating the models.
- viii.
- The morphology of the optimized specimen revealed dispersion of the particles within the matrix, proving that the optimum mix is fit for the design of green-Al6061 as an automobile material.

## Author Contributions

## Funding

## Institutional Review Board Statement

## Informed Consent Statement

## Data Availability Statement

## Acknowledgments

## Conflicts of Interest

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**Figure 2.**Morphological image of input materials (

**a**) steel particles (

**b**) palm kernel ash (

**c**) rice husk ash and their (

**d**) XRD.

**Figure 4.**Morphology and EDS analysis of specimens prepared at 700 °C containing (

**a**,

**b**) 2% PKA and 4% RHA (

**c**,

**d**) 4% PKA and 2% RHA; specimens prepared at 800 °C containing (

**e**,

**f**) 2% PKA and 6% RHA (

**g**,

**h**) 6% PKA and 2% RHA.

**Figure 5.**Morphology of specimens cast at 900 °C with a formulation of 4% PKA/6% RHA expressed in (

**a**) SEM image (

**b**) EDS result for the matrix (

**c**) polarized illumination (Amscope 40×−1000× fluorescence microscope) and EDS results on (

**d**) spot 1 (

**e**) spot 2 (

**f**) spot 3 (

**g**–

**j**) elemental maps.

**Figure 6.**Morphology of specimen cast at 900 °C with a formulation of 6% PKA/4% RHA expressed in (

**a**) SEM image (

**b**) EDS result for the matrix (

**c**) fluorescence morphology and EDS results on (

**d**) spot 1 (

**e**) spot 2 (

**f**) spot 3 (

**g**–

**j**) elemental maps.

**Figure 7.**Normal probability plot for responses (

**a**) tensile strength, (

**b**) tensile modulus, (

**c**) compressive strength, (

**d**) compressive modulus, and (

**e**) flexural strength.

**Figure 8.**Predicted vs. actual plot for responses (

**a**) tensile strength, (

**b**) tensile modulus, (

**c**) compressive strength, (

**d**) compressive modulus, and (

**e**) flexural strength.

**Figure 9.**Surface plots representing the relationship of the variables that affect tensile strength as revealed by interactions (

**a**) PKA vs. RHA (

**b**) PKA vs. stirring temperature (

**c**) RHA vs. stirring temperature.

**Figure 10.**Surface plots representing the relationship of the variables affect tensile modulus as revealed by interactions (

**a**) PKA vs. RHA (

**b**) PKA vs. stirring temperature (

**c**) RHA vs. stirring temperature.

**Figure 11.**Surface plots representing the relationship of the variables that affect compressive strength as revealed by interactions (

**a**) PKA vs. RHA (

**b**) PKA vs. stirring temperature (

**c**) RHA vs. stirring temperature.

**Figure 12.**Surface plots representing the relationship of the variables affect compressive modulus as revealed by interactions (

**a**) PKA vs. RHA, (

**b**) PKA vs. stirring temperature, and (

**c**) RHA vs. stirring temperature.

**Figure 13.**Surface plots representing the relationship of the variables that affect flexural strength as revealed by interactions (

**a**) PKA vs. RHA, (

**b**) PKA vs. stirring temperature, and (

**c**) RHA vs. stirring temperature.

**Figure 18.**Characteristics of a sample prepared at optimum condition (

**a**) microstructural features, (

**b**) EDS elemental composition, (

**c**) XRD phase identification.

Variables | Low (−1) | Middle (0) | High (+1) |
---|---|---|---|

PKA dosage (wt.%) | 2 | 4 | 6 |

RHA dosage (wt.%) | 2 | 4 | 6 |

Stirring temperature (°C) | 700 | 800 | 900 |

Coded Levels | Factors | |||||
---|---|---|---|---|---|---|

Experimental Runs | A | B | C | PKA (%) | RHA (%) | Temperature (°C) |

1 | −1 | 0 | 1 | 2 | 4 | 900 |

2 | 0 | 1 | 1 | 4 | 6 | 900 |

3 | 1 | 1 | 0 | 6 | 6 | 800 |

4 | −1 | −1 | 0 | 2 | 2 | 800 |

5 | 1 | 0 | 1 | 6 | 4 | 900 |

6 | 0 | 1 | −1 | 4 | 6 | 700 |

7 | 0 | 1 | 0 | 2 | 6 | 800 |

8 | 1 | 0 | 0 | 6 | 2 | 800 |

9 | 1 | 0 | 0 | 6 | 4 | 700 |

10 | 0 | −1 | −1 | 4 | 2 | 700 |

11 | −1 | 0 | −1 | 2 | 4 | 700 |

12 | 0 | −1 | 1 | 4 | 2 | 900 |

13 | 0 | 0 | 0 | 4 | 4 | 800 |

14 | 0 | 0 | 0 | 4 | 4 | 800 |

15 | 0 | 0 | 0 | 4 | 4 | 800 |

Properties | Density (g/cm^{3}) | Hardness (HRB) | Tensile Strength (MPa) | Young Modulus (GPa) | Flexural Strength (MPa) | Compressive Strength (MPa) |
---|---|---|---|---|---|---|

Value | 2.76 ± 0.20 | 83.0 ± 1.3 | 241.6 ± 4.5 | 60.3 ± 2.6 | 255.5 ± 3.9 | 209.8 ± 2.7 |

Materials | SiO_{2} | MgO | Al_{2}O_{3} | Fe_{2}O_{3} | CaO | K_{2}O | P_{2}O_{5} | MnO_{2} | Other |
---|---|---|---|---|---|---|---|---|---|

PKA | 47.3 | 4.2 | 6.9 | 3.0 | 20.2 | 6.8 | 4.1 | 3.5 | 4.0 |

RHA | 90.2 | 0.7 | 0.3 | 0.6 | 0.3 | 2.1 | 0.1 | 0.0 | 5.7 |

Elements | Cu | C | P | Cr | Si | Mn | Ni | Mo | S | Fe |
---|---|---|---|---|---|---|---|---|---|---|

Amount (%) | 0.1 | 0.3 | 0.00 | 0.1 | 0.2 | 0.6 | 0.1 | 0.1 | 0.1 | balance |

Experimental Runs | Designations | Tensile Strength (MPa) | Tensile Modulus (GPa) | Compressive Strength (MPa) | Compressive Modulus (GPa) | Flexural Strength (MPa) |
---|---|---|---|---|---|---|

1 | 2-4-900 | 322 ± 5.9 | 59 ± 1.4 | 243 ± 4.1 | 61 ± 1.1 | 291 ± 3.7 |

2 | 4-6-900 | 291 ± 5.1 | 76 ± 1.7 | 295 ± 5.0 | 77 ± 1.4 | 289 ± 3.3 |

3 | 6-6-800 | 303 ± 5.3 | 113 ± 2.6 | 330 ± 5.6 | 105 ± 2.3 | 297 ± 3.8 |

4 | 2-2-800 | 280 ± 5.0 | 76 ± 1.7 | 237 ± 3.9 | 56 ± 0.9 | 291 ± 3.7 |

5 | 6-4-900 | 289 ± 5.1 | 72 ± 1.7 | 281 ± 4.2 | 72 ± 1.1 | 277 ± 3.3 |

6 | 4-6-700 | 268 ± 3.8 | 85 ± 2.0 | 280 ± 4.1 | 77 ± 1.6 | 281 ± 4.1 |

7 | 2-6-800 | 300 ± 3.4 | 103 ± 2.4 | 302 ± 4.8 | 87 ± 1.6 | 322 ± 3.9 |

8 | 6-2-800 | 294 ± 5.2 | 91 ± 2.1 | 269 ± 4.3 | 72 ± 1.1 | 298 ± 3.2 |

9 | 6-4-700 | 275 ± 5.2 | 84 ± 1.9 | 273 ± 4.3 | 69 ± 1.4 | 281 ± 1.8 |

10 | 4-2-700 | 250 ± 4.1 | 65 ± 1.5 | 222 ± 3.1 | 48 ± 0.7 | 258 ± 1.6 |

11 | 2-4-700 | 271 ± 4.6 | 67 ± 1.5 | 235 ± 3.0 | 50 ± 0.8 | 279 ± 3.3 |

12 | 4-2-900 | 273 ± 4.8 | 56 ± 1.3 | 229 ± 3.6 | 46 ± 0.5 | 270 ± 3.2 |

13 | 4-4-800 | 342 ± 5.3 | 96 ± 2.2 | 278 ± 4.2 | 83 ± 1.4 | 338 ± 4.2 |

14 | 4-4-800 | 344 ± 6.0 | 93 ± 2.1 | 288 ± 4.5 | 78 ± 1.2 | 340 ± 4.5 |

15 | 4-4-800 | 345 ± 5.3 | 91 ± 2.1 | 279 ± 3.9 | 81 ± 1.5 | 335 ± 3.0 |

(a) Tensile Strength (TS) | (b) Tensile Modulus (TM) | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|

Source | SS | df | MS | F-v | p-v | Source | SS | df | MS | F-v | p-v |

Model | 9726.61 | 9 | 1080.73 | 20.56 | 0.0053 | Model | 3675.46 | 9 | 408.38 | 89.51 | 0.0003 |

A-PKA | 4560.50 | 1 | 660.50 | 11.15 | 0.0438 | A-PKA | 378.12 | 1 | 378.12 | 82.88 | 0.0008 |

B-RHA | 703.13 | 1 | 703.13 | 13.38 | 0.0216 | B-RHA | 990.13 | 1 | 990.13 | 217.01 | 0.0001 |

C-Temp. | 1540.13 | 1 | 1540.13 | 29.30 | 0.0056 | C-Temp. | 180.50 | 1 | 180.50 | 39.56 | 0.0033 |

AB | 0.2500 | 1 | 0.2500 | 0.0048 | 0.9483 | AB | 6.25 | 1 | 6.25 | 1.37 | 0.3068 |

AC | 342.25 | 1 | 342.25 | 6.51 | 0.0632 | AC | 4.00 | 1 | 4.00 | 0.8767 | 0.4021 |

BC | 0.0000 | 1 | 0.0000 | 0.0000 | 1.0000 | BC | 0.0000 | 1 | 0.0000 | 0.0000 | 1.0000 |

A² | 845.00 | 1 | 845.00 | 16.08 | 0.0160 | A² | 1.25 | 1 | 1.25 | 0.2740 | 0.6283 |

B² | 3920.00 | 1 | 3920.00 | 74.58 | 0.0010 | B² | 1.25 | 1 | 1.25 | 0.2740 | 0.6283 |

C² | 4500.00 | 1 | 4500.00 | 85.61 | 0.0008 | C² | 1940.45 | 1 | 1940.45 | 425.30 | 0.0001 |

Residual | 210.25 | 4 | 52.56 | Residual | 18.25 | 4 | 4.56 | ||||

Lack of Fit | 208.25 | 3 | 69.42 | 34.71 | 0.1240 | Lack of Fit | 13.75 | 3 | 4.58 | 1.02 | 0.6052 |

Pure Error | 2.00 | 1 | 2.00 | Pure Error | 4.50 | 1 | 4.50 | ||||

Cor Total | 9936.86 | 13 | Cor Total | 3693.71 | 13 | ||||||

R^{2} = 0.9788 | R^{2} (adj) = 0.9512 | R^{2} (pred) = 0.9339 | R^{2} = 0.9751 | R^{2} (adj) = 0.9639 | R^{2} (pred) = 0.9622 |

(a) Compressive Strength | (b) Compressive Modulus | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|

Source | SS | df | MS | F-v | p-v | Source | SS | df | MS | F-v | p-v |

Model | 12,233.00 | 9 | 1359.22 | 81.15 | 0.0004 | Model | 3542.43 | 9 | 393.60 | 32.46 | 0.0022 |

A-PKA | 2664.50 | 1 | 2664.50 | 159.07 | 0.0002 | A-PKA | 512.00 | 1 | 512.00 | 42.23 | 0.0029 |

B-RHA | 7200.00 | 1 | 7200.00 | 429.85 | 0.0000 | B-RHA | 1922.00 | 1 | 1922.00 | 158.52 | 0.0002 |

C-Temperature | 180.50 | 1 | 180.50 | 10.78 | 0.0304 | C-Temperature | 18.00 | 1 | 18.00 | 1.48 | 0.2900 |

AB | 9.00 | 1 | 9.00 | 0.5373 | 0.5042 | AB | 1.0000 | 1 | 1.0000 | 0.0825 | 0.7882 |

AC | 0.0000 | 1 | 0.0000 | 0.0000 | 1.0000 | AC | 16.00 | 1 | 16.00 | 1.32 | 0.3147 |

BC | 16.00 | 1 | 16.00 | 0.9552 | 0.3837 | BC | 1.0000 | 1 | 1.0000 | 0.0825 | 0.7882 |

A² | 0.2000 | 1 | 0.2000 | 0.0119 | 0.9182 | A² | 0.2000 | 1 | 0.2000 | 0.0165 | 0.9040 |

B² | 5.00 | 1 | 5.00 | 0.2985 | 0.6139 | B² | 1.80 | 1 | 1.80 | 0.1485 | 0.7196 |

C² | 2040.20 | 1 | 2040.20 | 121.80 | 0.0004 | C² | 1008.20 | 1 | 1008.20 | 83.15 | 0.0008 |

Residual | 67.00 | 4 | 16.75 | Residual | 48.50 | 4 | 12.13 | ||||

Lack of Fit | 17.00 | 3 | 5.67 | 0.1133 | 0.9410 | Lack of Fit | 36.00 | 3 | 12.00 | 0.9600 | 0.6174 |

Pure Error | 50.00 | 1 | 50.00 | Pure Error | 12.50 | 1 | 12.50 | ||||

Cor Total | 12,300.00 | 13 | Cor Total | 3590.93 | 13 | ||||||

R^{2} = 0.9826 | R^{2} (adj) = 0.9723 | R^{2} (pred) = 0.9596 | R^{2} = 0.9865 | R^{2} (adj) = 0.9561 | R^{2} (pred) = 0.9527 |

(a) Flexural Strength | |||||
---|---|---|---|---|---|

Source | SS | df | MS | F-v | p-v |

Model | 7694.96 | 9 | 855.00 | 32.81 | 0.0021 |

A-PKA | 300.13 | 1 | 300.13 | 11.52 | 0.0274 |

B-RHA | 1035.13 | 1 | 1035.13 | 39.72 | 0.0032 |

C-Temperature | 98.00 | 1 | 98.00 | 3.76 | 0.1245 |

AB | 42.25 | 1 | 42.25 | 1.62 | 0.2719 |

AC | 64.00 | 1 | 64.00 | 2.46 | 0.1922 |

BC | 4.00 | 1 | 4.00 | 0.1535 | 0.7152 |

A² | 938.45 | 1 | 938.45 | 36.01 | 0.0039 |

B² | 1940.45 | 1 | 1940.45 | 74.45 | 0.0010 |

C² | 5088.05 | 1 | 5088.05 | 195.22 | 0.0002 |

Residual | 104.25 | 4 | 26.06 | ||

Lack of Fit | 102.25 | 3 | 34.08 | 17.04 | 0.1758 |

Pure Error | 2.00 | 1 | 2.00 | ||

Cor Total | 7799.21 | 13 | |||

R^{2} = 0.9866 | R^{2} (adj) = 0.9666 | R^{2} (pred) = 0.9592 |

Name | Goal | Lower Limit | Upper Limit | Importance |
---|---|---|---|---|

A: PKA | is in range | 2 | 6 | 3 |

B: RHA | is in range | 2 | 6 | 3 |

C: Temp. | is in range | 700 | 900 | 3 |

CS | maximize | 222 | 330 | 3 |

CM | maximize | 46 | 105 | 3 |

TS | maximize | 250 | 344 | 3 |

TM | maximize | 56 | 113 | 3 |

FS | maximize | 258 | 340 | 3 |

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## Share and Cite

**MDPI and ACS Style**

Akinwande, A.A.; Adesina, O.S.; Adediran, A.A.; Balogun, O.A.; Mukuro, D.; Balogun, O.P.; Tee, K.F.; Kumar, M.S.
Microstructure, Process Optimization, and Strength Response Modelling of Green-Aluminium-6061 Composite as Automobile Material. *Ceramics* **2023**, *6*, 386-415.
https://doi.org/10.3390/ceramics6010023

**AMA Style**

Akinwande AA, Adesina OS, Adediran AA, Balogun OA, Mukuro D, Balogun OP, Tee KF, Kumar MS.
Microstructure, Process Optimization, and Strength Response Modelling of Green-Aluminium-6061 Composite as Automobile Material. *Ceramics*. 2023; 6(1):386-415.
https://doi.org/10.3390/ceramics6010023

**Chicago/Turabian Style**

Akinwande, Abayomi Adewale, Olanrewaju Seun Adesina, Adeolu Adesoji Adediran, Oluwatosin Abiodun Balogun, David Mukuro, Oluwayomi Peter Balogun, Kong Fah Tee, and M. Saravana Kumar.
2023. "Microstructure, Process Optimization, and Strength Response Modelling of Green-Aluminium-6061 Composite as Automobile Material" *Ceramics* 6, no. 1: 386-415.
https://doi.org/10.3390/ceramics6010023