Issue 70

P. Kulkarni et alii, Frattura ed Integrità Strutturale, 70 (2024) 71-90; DOI: 10.3221/IGF-ESIS.70.04

Validatory experiments Turning experiments are conducted to validate the ANN and ANFIS predicted responses at process parameters than those were used while training the ANN and ANFIS models. Tab. 6 compares the experimental findings with the anticipated ANN and ANFIS predicted responses. This additional experiment provided a robust assessment of the models' performance across a wider range of input parameters. The experimental values shown for cutting force, surface roughness, and tool life are averages of measurements taken at three repeated trials for a tool, aiming to minimize outliers before analyzing the data. The percentage error in predicted responses by ANN and ANFIS from validatory experimental findings is as shown in Tab. 7. With an average error of less than 15%, there is a good agreement between the experimental findings and the ANN and ANFIS predicted results.

Surface roughness   Ra (µm)

Cutting force   Fc (N)

Tool life   TL (min)

Depth of cut ( d ) (mm)

Cutting speed ( V ) (m/min)

Feed ( f ) (mm/rev)

Expt. run

Expt.

ANN

ANFIS Expt. ANN

ANFIS

Expt. ANN ANFIS

1

55

0.22

0.55

426

464.10

394.01

1.65

1.48

1.73

6.13

6.69

6.36

2

35

0.18

0.3

182

189.83

205.93

1.29

1.38

1.19

14.54 13.08

16.31

3

60

0.1

0.45

178

213.26

144.57

0.84

0.98

0.85

8.66

9.56

8.47

Table 6: Validation experiments.

% absolute error in cutting force   Fc (N)

% absolute error in surface roughness   Ra (µm)

% absolute error in tool life   TL (min)

Cutting speed ( V ) (m/min)

Depth of cut ( d ) (mm)

Feed ( f ) (mm/rev)

Expt. run

ANN

ANFIS

ANN 10.07

ANFIS

ANN

ANFIS

1

55

0.22

0.55

8.94

7.51

4.89

9.15

3.81

2

35

0.18

0.3

4.30

13.15

6.78

7.71

10.07

12.15

3

60

0.1

0.45

19.81

18.78

16.07

0.81

10.35

2.21

% absolute average error

11.02

13.15

10.97

4.47

9.86

6.05

Table 7: % absolute error in ANN and ANFIS predicted results from the validatory experimental results. The results of the validatory experiments showed that both models were able to accurately predict outcomes within the specified range, further validating their predictive capabilities. This study finds that the soft computing techniques such as ANN and ANFIS could be reliably used to model turning of Inconel 718 under NFMQL cutting conditions. In comparison to ANN, the ANFIS technique proved to be more accurate in forecasting surface roughness and tool life within a restricted range of process parameters and limited experimental findings. The accuracy of cutting force prediction with both models did not, however, differ much. Overall, the results demonstrate the effectiveness of both models in accurately predicting outcomes across various input parameters. This comprehensive analysis enhances our understanding of the predictive capabilities of these models in real world applications. However, by using hybrid optimization techniques to optimize membership function parameters, this study recommends more research on the modeling of Inconel 718 machining using ANFIS. Further exploration of different machining parameters and their effects on the ANFIS model could provide valuable insights for improving the accuracy and efficiency of Inconel 718 machining processes. Additionally, comparing the performance of ANFIS with other machine learning techniques in this context may offer a comprehensive understanding of its capabilities and limitations. C ONCLUSIONS ickel alloys' low heat conductivity and poor machinability cause severe damage to cutting tools during machining, leading to increased manufacturing costs. It is essential to develop models to predict machining parameters to increase production efficiency, save costs, and ensure quality. Soft computing techniques, with their self-learning N

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