Indian Journal of

       Engineering & Materials Sciences

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VOLUME 16
CODEN : IEMSEW

NUMBER 6

DECEMBER 2009
ISSN : 0971-4588

   

CONTENTS
 
   
   

Surface properties of the cut face obtained by different cutting methods from AISI 304 stainless steel materials

373

      Adnan Akkurt

 

 

 

Influence of key test parameters on SPT results

385

      K K Pathak, K K Dwivedi,  Manali Shukla & E Ramadasan

 

 

 

Effect of Ni doping on structural and dielectric properties of BaTiO3

390

      Yogeswar Kumar , Md Ahamad Mohiddon, Alok Srivastava & K L Yadav

 

 

 

Dielectric dispersion and ionic conduction in hydrocolloids of poly(vinyl alcohol)–poly(ethylene oxide) blend–montmorillonite clay nanocomposites

395

      R J Sengwa, Shobhna Choudhary & Sonu Sankhla

 

 

 

Investigations on poly(aniline-co-o-toluidine)/polystyrene sulphonic acid composite

403

      Neetika Gupta & D Kumar

 

 

 

Synthesis of Mn0.2Zn0.8Fe2O4 particles by high energy ball milling and  their applications

410

      Nitu Kumar, Vinod Kumar, Manju Arora, Monika Sharma, Bhikham Singh &

 

      R P Pant

 

 

 

Studies on SCLA composite Portland cement

415

      N B Singh, S S Das, N P Singh & V N Dwivedi

 

 

 

Thermolysis of pyridinium perchlorate salts

423

      Pratibha Srivastava, I P S  Kapoor &  G Singh

 

 

 

A new method to predict activation energies of nitroparaffins

429

      M H Keshavarz

 

 

 

Free vibration of layered annular circular plate of variable thickness using spline function approximation

433

      K K Viswanathan & Dongwoo Sheen  

 

 

 

Two different methods for improving the properties of  IC-221M alloy

449

      Ali Reza Kamali, Morteza Hadi & Masoud Nazarian-Samani

 

 

 

Acknowledgement to Reviewers

457

 

 

Annual  Index

 

 

 

Subject  Index

463

 

 

Author  Index

477

 

 

 

Indian Journal of Engineering & Materials Sciences

Vol. 16, December 2009, pp. 373-384

 


Surface properties of the cut face obtained by different cutting methods from
AISI 304 stainless steel materials

Adnan Akkurt

 

AISI 304 stainless steel which is widely used almost in all industrial applications is accounted for approximately 50% of the world’s stainless steel production and consumption. Because of its aesthetic view in architectures, resistance against corrosion and chemicals, it became as the most preferred material. Today several methods for machining of AISI 304 stainless steel are available. Most of these methods result in loss of superior properties of the stainless steel material and makes it to act like other ordinary materials within the machined zones. In this study, specimens taken from the AISI 304 material are cut by the cutting methods which are commonly used in machining. The resulting surface properties of these specimens are compared with original materials with respect to different methods. Finally mechanical and metallurgical properties of the cut face obtained by each method are examined. The results show that cutting with abrasive water jet gives the most favorable result while oxygen cutting gives the worst.

Keywords: Cutting methods, Comparison of cutting methods, AISI 304 stainless steel material, Surface characteristic, Surface quality

 

 

 

Indian Journal of Engineering & Materials Sciences

Vol. 16, December 2009, pp. 385-389

Influence of key test parameters on SPT results

 

K K Pathak, K K Dwivedi, Manali Shukla & E Ramadasan

 

In order to assess the strength of aged material during the service life, small punch test (SPT) has emerged as a powerful NDT tool of engineers. It is a promising technique for those circumstances where only a small amount of material is available for characterization. SPT involves use of small size samples tested by bending or shearing to fracture in a specially designed die and punch assembly. As the sample and tooling sizes go down, the sensitivity of test parameters on the SPT output becomes an important issue. In order to get realistic material properties, sensitivity of test parameters should be studied. The parameters found to be critical can be given due attention. In this study, influence of several key parameters like fillet radius, ball diameter, sample thickness, yield stress and friction are studied using finite element simulations and their effects are critically examined. The analyses indicate that yield stress is less sensitive parameter as it does not affect peak load and corresponding displacement but fillet radius, ball diameter, plate thickness and friction considerably affect the value of peak load and corresponding displacement. So, these parameters must be precisely and carefully measured during small punch tests. Based on these findings, experimental load stroke data, obtained due to faulty test parameters, may be corrected rather than going for a new test with correct parameters.

 

Keywords: Small punch, stress, strain, finite element, load stroke

 

 

 

Indian Journal of Engineering & Materials Sciences

Vol. 16, December 2009, pp. 390-394

                          

 

Effect of Ni doping on structural and dielectric properties of BaTiO3

Yogeswar Kumar, Md Ahamad Mohiddon, Alok Srivastava & K L Yadav

 

Polycrystalline samples of Ba1-xNixTiO3 (BNT), where x = 0, 0.03, 0.05, 0.07 and 0.10 have been synthesized by solid-state reaction technique. No phase change in the crystal structure has been observed with Ni doping in barium titanate up to x = 0.10, however a decrease in crystallite size, lattice strain, c/a ratio and grain size has been found with Ni doping. The different results presented may be related to, and are explained by, the grain size and its distribution in the ceramic bulk. Ni doping in BaTiO3 exhibit many interesting features, such as shift in transition temperature, increasing diffuse phase transition and decreasing dielectric constant. The evolution from a normal ferroelectric phase transition to a diffuse phase transition has been observed with increasing Ni concentrations. The dielectric study of samples poled in magnetic field (data shown for BNT, x = 0.03 here) suggests that Tc and maximum dielectric constant increase with increasing magnetic poling strength along with decreasing nature of diffusivity thus showing multiferroic nature.

Keywords: Ceramics, X-ray diffraction, Dielectric properties, Grain size, Diffuse phase transition

 

 

 

Indian Journal of Engineering & Materials Sciences

Vol. 16, December 2009, pp. 395-402

 

 

Dielectric dispersion and ionic conduction in hydrocolloids of poly
(vinyl alcohol)–poly(ethylene oxide) blend–montmorillonite clay nanocomposites

R J Sengwa, Shobhna Choudhary & Sonu Sankhla

 

The relative complex dielectric function, electric modulus, alternating current (ac) electrical conductivity and complex impedance spectra of poly(vinyl alcohol) (PVA)–poly(ethylene oxide) (PEO) blend loaded with montmorillonite (MMT) clay nano-platelets up to 10 wt.% in aqueous colloidal suspensions are investigated over the frequency range 20 Hz - 1 MHz at 27oC. The relaxation time corresponding to electrode polarization and ionic conduction processes are determined from the complex spectra of intensive dielectric quantities. The direct current (dc) electrical conductivity of these materials is evaluated by the fitting of real part ac conductivity data to the Jonscher power law, which increases significantly at higher clay concentration. The behaviour of ionic conduction with increase of clay concentration is discussed considering intercalation of the polymers blend in clay galleries with the formation of lamellar nanostructures, and the effect of exfoliated MMT clay nanoplatelets on these structures. Contribution of PVA and PEO on the ionic conduction and electrode polarization phenomena is explored in the hydrocolloids of PVA–PEO blend –MMT clay from the comparative study of various dielectric parameters with the PVA–MMT clay and PEO–MMT clay hydrocolloids.

 

 

Indian Journal of Engineering & Materials Sciences

Vol. 16, December 2009, pp. 403-409

 

 

Investigations on poly(aniline-co-o-toluidine)/polystyrene sulphonic acid composite

 

Neetika Gupta & D Kumar

 

Poly(aniline-co-o-toluidine) is synthesized by free radical chemical oxidative copolymerization of aniline with o-toluidine using ammonium persulphate as an oxidant in protonic acid medium. This copolymer (COP) has been introduced into polystyrene sulphonic acid (PSSA) in 2:1, 1:1 and 1:2 compositions for the preparation of composite materials. The composite samples so obtained are characterized by UV-visible, FTIR, TGA, DSC, XRD and SEM techniques. The incorporation of copolymer in PSSA has been endorsed by FTIR analysis. TGA data reveal that the COP/PSSA (2:1) composite shows better thermal stability than COP/PSSA (1:1) and COP/PSSA (1:2) composites. Two step transitions are clearly reported from the DSC thermograms of COP/PSSA composites. SEM micrographs reveal distinct morphological features of these composites.

Keywords:   Conducting polymer, Chemical oxidative copolymerization, Poly(aniline-co-o-toluidine), Polystyrene sulphonic acid, Composite

 

 

 

Indian Journal of Engineering & Materials Sciences

Vol. 16, December 2009, pp. 410-414

 

 

Synthesis of Mn0.2Zn0.8Fe2O4 particles by high energy ball milling and their applications

Nitu Kumar, Vinod Kumar, Manju Arora, Monika Sharma, Bhikham Singh & R P Pant

 

Ultra fine Mn0.2Zn0.8Fe2O4 magnetic particles are developed by high energy ball milling technique and investigated for physical properties. The crystalline phase, crystallite size, surface morphology, metal oxide bonding and porosity of these magnetic particles are analyzed. The porosity increases on increasing the grinding period due to decrease in the particle size and crystallinity reduces. The IR spectra measured in the range of 4000-400 cm-1 exhibit symmetric stretching mode of (FeO4) and (ZnO4) tetrahedral at 669.7 cm-1 and 545.6 cm-1. The lattice strain induced by ball milling process has been determined. The porosity plays an important role in chemisorption and physisorption of species on the sites of the particles. This property of these particles has been exploited for the applications of humidity sensor.

Keywords: Ferrite, Crystallite size, Ball milling, Humidity sensing, Mn-Zn ferrite, FTIR spectra

 

 

 

Indian Journal of Engineering & Materials Sciences

Vol. 16, December 2009, pp. 415-422

 

Studies on SCLA composite Portland cement

N B Singh, S S Das, N P Singh & V N Dwivedi

 

Ecofriendly composite cements may be obtained by partial replacement of Portland cement with certain low cost materials. Sugarcane leaf ash (SCLA) is one such material which is obtained by firing sugar cane leaf in an open atmosphere and then calcined at 6000C for 2 h in a muffle furnace under oxygen atmosphere. Hydration of 10 wt% SCLA composite Portland cement was studied by using powder X-ray diffraction, FTIR spectroscopy, differential scanning calorimetric and other techniques. The results have shown that the pozzolanic reaction of sugarcane leaf ash increases with time. The compressive strength of 10 wt% SCLA composite Portland cement at 28 days of hydration is comparable to that of OPC alone.

 

 

 

Indian Journal of Engineering & Materials Sciences

Vol. 16, December 2009, pp. 423-428

 

Thermolysis of pyridinium perchlorate salts

 

Pratibha Srivastava, I P S Kapoor & G Singh

 

Three perchlorate salts of pyridine have been prepared and characterized by gravimetric and elemental analyses. Thermogravimetry (TG) and differential thermal analysis (DTA) have been carried out in static air, to examine the thermal decomposition process of these salts. Isothermal TG of these salts have been done to evaluate the kinetics of thermal decomposition in the temperature range 290-410oC using both model fitting and isoconversional methods. Isoconversional method has been found to be superior over conventional model fitting method and is able to describe the decomposition process of these salts. Moreover, Explosion delay (DE) measurements have been carried out to investigate the response of the salts under the condition of rapid heating.

Keywords: Thermal decomposition; isothermal TG; model fitting; iso-conversional; explosion delay

 

 

 

Indian Journal of Engineering & Materials Sciences

Vol. 16, December 2009, pp. 429-432

 

 

A new method to predict activation energies of nitroparaffins

M H Keshavarz

 

A novel relationship has been derived to predict the activation energies (Ea) of low-temperature non-autocatalyzed thermolysis of nitroparaffins through suitable combination of elemental composition. The new correlation of Ea is based on the experimental data using the isothermal monomethric method, which is useful method to examine the kinetics of thermolysis of energetic materials in vacuum. The new method uses the optimized number of carbon, hydrogen and oxygen divided by molecular weight of nitroparaffins to obtain a reliable correlation. The new correlation is a general relationship because it can be applied for various nitroparafifins as compared to previous method which uses oxygen balance for some specific groups of mentioned compounds. R-squared value or the coefficient of determination of the new correlation is 0.954.

 

 

Indian Journal of Engineering & Materials Sciences

Vol. 16, December 2009, pp. 433-448

 

 

Free vibration of layered annular circular plate of variable thickness
using spline function approximation

 

K K Viswanathan & Dongwoo Sheen

 

Free vibration of layered annular circular plate of variable thickness, made up of isotropic or specially orthotropic materials, is studied using spline function approximation by applying the point collocation method. Three different thickness variations are considered, namely, linear, exponential and sinusoidal, along the radial directions. The equations of motion are derived by extending Love’s first approximation theory. A system of coupled differential equations, in terms of longitudinal, circumferential and transverse displacement functions is obtained by assuming the solution in a separable form. These functions are approximated by using Bickley-type splines of suitable orders. A generalized eigenvalue problem is obtained by applying a point collocation technique with suitable boundary conditions, from which the values of a frequency parameter and the corresponding mode shapes of vibration, for specific values of various parameters, are obtained.

 

Keywords:   Free vibration, Annular plate, Variable thickness, Spline, Eigenvalue

 

 

 

Indian Journal of Engineering & Materials Sciences

Vol. 16, December 2009, pp. 449-455

 

 

Two different methods for improving the properties of IC-221M alloy

Ali Reza Kamali, Morteza Hadi & Masoud Nazarian-Samani

 

The formation of the Ni-Ni5Zr eutectic structure is the most important reason for the impoverished mechanical properties of the Ni3Al-based alloy containing Zr. On the other hand, this low melting point phase has a positive effect on castability of the alloy. Two different methods are used in this study for the development of a Ni5Zr-free structure. In the first method, arc remelting process, using Mo3Al8, ZrAl3 and NiAl master alloys, followed by a proper heat treatment led to the production of a modified Ni3Al-based alloy. In the second method, a powder metallurgy process is used to replace the casting method, thereby, lifting the need for Zr addition. A Ni3Al-based alloy containing Mo, Cr, and B is produced via mechanical alloying followed by hot pressing densification. The alloys thus produced are studied for their improved yield strengths.

Keywords: IC-221M, Ni5Zr, Heat treatment, Powder metallurgy

Acknowledgement to Reviewers

 

Annual Subject  Index

 

Annual Author  Index