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Effects of Cutting Parameters on Quality of Surface Produced by Machining of Titanium Alloy and Their Optimization

Niharika, Agrawal B. P., Khan I. A., Khan Z. A.

Archive of Mechanical Engineering

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2016

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Vol. LXIII, nr 4

531--548

EN

Titanium alloy (Ti-6Al-4V) has been extensively used in aircraft turbine-engine components, aircraft structural components, aerospace fasteners, high performance automotive parts, marine applications, medical devices and sports equipment. However, wide-spread use of this alloy has limits because of difficulty to machine it. One of the major difficulties found during machining is development of poor quality of surface in the form of higher surface roughness. The present investigation has been concentrated on studying the effects of cutting parameters of cutting speed, feed rate and depth of cut on surface roughness of the product during turning of titanium alloy. Box-Behnken experimental design was used to collect data for surface roughness. ANOVA was used to determine the significance of the cutting parameters. The model equation is also formulated to predict surface roughness. Optimal values of cutting parameters were determined through response surface methodology. A 100% desirability level in the turning process for economy was indicated by the optimized model. Also, the predicted values that were obtained through regression equation were found to be in close agreement to the experimental values.

PL

Stop tytanu (Ti-6Al-4V) jest szeroko stosowany do budowy elementów turbinowych silników lotniczych i innych podzespołów samolotów, elementów złącznych w technice lotniczej i astronautycznej, wysokiej jakości części samochodowych, w technice okrętowej i medycznej, a także w sprzęcie sportowym. Niemniej, powszechne zastosowanie tego stopu jest ograniczone trudnościami z jego obróbką. Jednym z podstawowych problemów jest niska jakość obrabianej powierzchni, która charakteryzuje się znaczną chropowatością. Przedstawiona praca jest poświęcona badaniu wpływu parametrów skrawania, takich jak szybkość skrawania, szybkość posuwu i głębokość skrawania na chropowatość powierzchni uzyskaną w procesie toczenia stopu tytanu. Przy zbieraniu danych nt. chropowatości powierzchni wykorzystano planowanie eksperymentu metodą Boxa-Behnkena. Do określenia poziomu istotności parametrów skrawania zastosowano metodę analizy wariancji, ANOVA. Sformułowano także równania modelu, pozwalającego przewidzieć chropowatość powierzchni. Optymalne wartości parametrów skrawania wyznaczono, stosując metodę powierzchni odpowiedzi (RSM). Wartości parametrów wyznaczone na podstawie równań regresji są bardzo bliskie wartościom uzyskanym eksperymentalnie.

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A Study on the Combined Effect of Noise and Vibration on the Performance of a Readability Task in a Mobile Driving Environment by Operators of Different Ages

Khan I. A., Mallick Z., Khan Z. A., Muzammil M.

International Journal of Occupational Safety and Ergonomics

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2009

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Vol. 15, No. 3

277--286

EN

This study investigated the combined effect of noise and vibration on the performance of a readability task in a mobile driving environment by operators of different ages. Subjects performed a readability task on a laptop computer in a sitting posture without their backs supported under varying levels of noise and vibration. Data in terms of a mean number of characters read per minute were collected and statistically analyzed. Results showed that the individual effects of noise, vibration, and operators’ age as well as the interaction between operators’ age and vibration were statistically significant. However, the combined effect of noise and vibration was not found to be statistically significant. Results also indicated that the operators’ age was statistically significant at all levels of vibration and vibration was statistically significant at all levels of operators’ age.

3

A Study on the Combined Effect of Noise and Vibration on Operators’ Performance of a Readability Task in a Mobile Driving Environment

Khan I. A., Mallick Z., Khan Z. A.

International Journal of Occupational Safety and Ergonomics

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2007

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Vol. 13, No. 2

127--136

EN

This paper presents a study in which the main objective was to investigate the combined effect of noise and vibration on the performance of a readability task in a mobile driving environment. Subjects performed a readability task on a laptop computer in a sitting posture with their backs supported with a backrest under varying levels of noise and vibration. The data in terms of the mean number of characters read per minute were collected and statistically analyzed. Results showed that the individual effect of noise, vibration, and the operators’ gender as well as the interaction between gender and noise, and gender and vibration were statistically significant. However, the combined effect of noise and vibration was not found to be statistically significant. Results also indicated that gender was statistically significant at all levels of noise as well as vibration, and noise and vibration were statistically significant at both levels of gender.

4

Thin-layer chromatographic separation of phenols with buffered mobile phases containing cationic surfactants

Mohammad A., Anwar S., Iraqi E., Khan I. A.

Acta Chromatographica

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2000

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No. 10

195-213

EN

The retention behaviour of nineteen phenols has been examined on plain and ethylenediamine tetraacetic acid (EDTA)-impregnated silica gel layers developed with buffered solutions of cetyltrimethylammonium bromide (CTAB). The effect of CTAB concentration and the nature of other additives (alcohols of different carbon-chain length and acetonitrile) on the RF value (or mobility) of the phenols was studied. Among the additives investigated, 5% methanol was found most suitable. Good separations of phenols were possible with 1% CTAB in 50:50:8 (v/v) 0.04 M boric acid–0.04 M phosphoric acid–0.24 M NaOH as mobile phase. Some important separations were achieved experimentally both on plain silica and on EDTA-impregnated layers.