Optimization of the surface roughness by applying the Taguchi technique for the turning of stainless steel under cooling conditions

Abstract

This paper presents the optimization of the surface roughness using the Taguchi technique to assess the machinability of the AISI 316Ti steel with PVD coated carbide inserts under different cooling conditions such as dry, conventional (wet) and cryogenic cooling with liquid nitrogen (LN2). Based on the Taguchi L9 (3 3 ) orthogonal-array design, the machinability tests were made utilizing a CNC lathe machine. Test parameters including the cutting speed, the cooling condition and the feed rate were taken and then the surface roughness (Ra) was measured to obtain the machinability indicator. An analysis of variance was performed to determine the importance of the input parameters for the surface roughness. The process parameters were optimized by taking the Taguchi technique into consideration. The Taguchi signal-to-noise ratio was employed with the smaller-the-better approach to obtain the best combination. On the basis of the first-order model, a mathematical model was created using the regression analysis to predict the Ra model. The results indicate that the feed rate is the parameter with the highest effect on the surface roughness and that the other parameters also have a statistical significance. In addition, cryogenic cooling is an alternative method for increasing the surface quality of machined parts. Keywords: AISI 316Ti, cryogenic cooling, machinability, optimization, surface roughness, Taguchi method lanek obravnava optimiranje hrapavosti povr{ine z uporabo Taguchi-jeve metode za oceno obdelovalnosti jekla AISI 316Ti s karbidnimi vlo`ki s PVD-nanosom v razli~nih razmerah ohlajanja, kot je suho, navadno (mokro) in kriogensko hlajenje s teko~im du{ikom (LN2). Preizkusi obdelovalnosti so bili izvr{eni s CNC-stru`nico na osnovi Taguchi-jevega ortogonalnega niza L9 (3 3 ). Izbrani so bili parametri preizkusov, hitrost rezanja, razmere pri ohlajanju in hitrost podajanja, nato pa je bila izmerjena hrapavost povr{ine (Ra) kot pokazatelj obdelovalnosti. Izvr{ene so bile analize variance, da bi ugotovili pomembnost vhodnih parametrov na hrapavost povr{ine. Procesni parametri so bili optimirani z upo{tevanjem Taguchi-jeve tehnike. Uporabljeno je bilo Taguchi-jevo razmerje signal -hrup s pribli`kom~im manj{e tem bolj{e za doseganje najbolj{e kombinacije. Na osnovi modela prvega reda je bil postavljen z uporabo regresijske analize matemati~ni model za napovedovanje Ra. Rezultati ka`ejo, da je hitrost podajanja parameter z najve~jim u~inkom na hrapavost povr{ine, vsi drugi parametri imajo statisti~no zna~ilnost. Dodatno je kriogensko ohlajanje alternativna metoda za pove~anje kvalitete povr{ine stru`enih delov.

Investigation and optimization of surface roughness with experimental design methods by turning of AISI-1050 after spheroidization heat treatment

“…8 were shaped according to the change in the feed rate parameter. Similar to the result obtained in this study, it has been understood that the feed rate parameter is the most dominant parameter in many different machining studies [7,14].…”

“…The effectiveness of other parameters is very low. This result was in parallel with several studies in the literature [6,13,14,18]. In order to better understand the effectiveness of the parameters, the % effectiveness value was calculated and plotted for each parameter in both methods (Fig.…”

“…This may be explained by the fact that the experiments carried out at 700 °C were affected less by the experimental conditions. Different studies have shown high consistency for both TM (96.8%- [14], 94%- [7]) and RSM (90.21%- [24], 82.5%- [22], 87.5%- [23]) in the optimization of machining operations. When these results were evaluated, it was understood that the analyses made with TM obtained the same results as the successful studies in the literature, and the analyses made with the RSM obtained more successful results compared to the studies in the literature.…”

“…The Taguchi approach showed that the feed rate was the most important parameter in the experiments. Sarikaya [14] estimated the surface roughness values obtained by turning stainless steel using a coolant with the Taguchi method. As a result of their study, they found that the feed rate was the parameter that was the most effective on surface roughness.…”

Optimization of the machining parameters for the turning of 15-5 PH stainless steels using the Taguchi method

“…21,22 The Taguchi method significantly decreases the number of tests needed and increases the machining performance by using orthogonal arrays. 23,24 For the realization of the experimental design, first of all, the control factors and their levels must be determined. In this study, the cutting tools (PVD and CVD), cutting speed (V), feed rate (f) and depth of cut (ap) were determined as the control factors.…”