Indian Journal of Engineering & Materials Science

 

 

 

 

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VOLUME 13

CODEN : IEMSEW

NUMBER 5

OCTOBER 2006

ISSN : 0971-4588

 

CONTENTS

 

Engineering

 

 

Dynamics of hydrogen in sodium in LMFBR secondary circuit

391

         Vivek Nema, D Sujish, B Muralidharan, M Rajan & G Vaidyanathan

 

         [IPC Code: G21C]

 

 

A comparative study of stress distribution in interference fitted assemblies

397

         Irappa Sogalad & N G Subramanya Udupa

 

         [IPC Code: G01L 1/00]

 

 

Determination of the effect of temperature and relative humidity on the friction coefficient of V-belt mechanism

 

405

         Abdulkadir Cengiz & Mehmet Uçar

 

         [IPC Code: F16H 13/00]

 

 

Experimental and analytical investigation of loosening and shakedown of the threaded joints

 

411

         Mindaugas Leonavičius, Algimantas Krenevičius, Marijonas Šukšta, Stanislav Stupak & Žilvinas Bazaras

 

         [IPC Code: F16L, G01N 3/00]

 

 

investigation of low cycle fatigue crack opening size and closure stress

417

         M Daunys & A Taraškevičius

 

         [IPC Code: G01N 3/00]

 

 

Materials Science

 

 

Influence of manganese ions on electrical, spectroscopic and magnetic properties of PbO-Al2O3-B2O3 glasses

 

426

         M Rami Reddy, G Naga Raju & N Veeraiah

 

         [IPC Code: C03C]

 

 

Elastic property evaluation of jute-glass fibre hybrid composite using experimental and CLT approach

 

435

         K Sabeel Ahmed & S Vijayarangan

 

         [IPC Code: C03C 14/00, C03C 17/32]

 

 

Preparation of rare earth oxide doped alumina ceramics, their hardness and fracture toughness determinations

 

443

         Kuntal Maiti & Anjan Sil

 

         [IPC Code: C04B 35/40]

 

A modified gun technique for melt quenching of reactive alloys

451

         V Venkateswara Rao

 

         [IPC Code: C22C 9/05]

 

 

Ionic transport in sodium phosphate glasses doped with chlorides of Co, Cd and Ag

455

         S S Das, Vibha Srivastava & P Singh

 

         [IPC Code: C03C 4/18]

 

 

Studies on energetic compounds Part 42 — Thermolysis of 5-amino-3-nitro-1,2,4-triazole (ANTA)

 

462

         G Singh, C P Singh, J PAgrawal & A K Sikder

 

         [IPC Code: C06B]

 

 

Corrosion fatigue of welded joints of steel for marine platform

467

         Yantao Li & Baorong Hou

 

         [IPC Code: G01N 3/00, G01N 17/00]

 

 

_______________

 

IPC: International Patent Classification

 

Int. Cl.8: International Classification 8th edition, 2006

 

 

 

 

Indian Journal of Engineering & Materials Sciences

Vol. 13, October 2006, pp. 391-396

 

Dynamics of hydrogen in sodium in LMFBR secondary circuit

 

Vivek Nema, D Sujish, B Muralidharan, M Rajan & G Vaidyanathan

 

Steam generator (SG) of a liquid metal cooled fast breeder reactor (LMFBR) comprises sodium on the shell side transferring heat to water in the tubes. Any crack in the tube will result in the water reacting with sodium producing hydrogen and other corrosive reaction products. This may lead to the damage of the neighbouring tubes. Monitoring of hydrogen concentration in sodium can indicate the initiation of a sodium water reaction (SWR). The hydrogen detectors are based on the diffusion of hydrogen in the sodium through a nickel membrane and measurement of the hydrogen concentration by a mass spectrometer. A numerical model has been developed to estimate the amount of hydrogen concentration in the secondary loop during water/steam leak in SG. The model has been validated based on experiments with hydrogen injection in one loop and actual sodium water reaction in another loop. It has been found that the increase in hydrogen concentration was very well predicted by the code.

IPC Code: G21C

 

Indian Journal of Engineering & Materials Sciences

Vol. 13, October 2006, pp. 397-404

 

 

A comparative study of stress distribution in interference fitted assemblies

Irappa Sogalad & N G Subramanya Udupa

 

Interference fitted assemblies find wide engineering applications such as bearing bushes, liners in cylinder blocks and small end bush in connecting rods. The strength of any such assemblies depends on various geometric features, amount of interference and other physical conditions of the mating surfaces. This paper presents the details of analysis carried out to study the effect of different pin and bush materials, low temperature (cryogenic) treatment and geometric parameters on stress distribution at the mating surface of interference fitted assemblies. This work covers, analysis based on Lame’s approach and finite element method – to evaluate the principal stresses and Von Mises stresses on the performance of interference fitted assemblies. For the finite element analysis(FEA), an appropriate finite element model was developed to analyse the pattern of contact stresses in interference fitted assemblies with and without low temperature effect and under varying geometric parameters such as contact length, mating diameter and amount of interference. A comparative study of both the methods has been carried out.

IPC Code: G01L1/00

 

Indian Journal of Engineering & Materials Sciences

Vol. 13, October, 2006, pp. 405-410

 

Determination of the effect of temperature and relative humidity on the friction coefficient of V-belt mechanism

Abdulkadir Cengiz & Mehmet Uçar

 

In the V-belt drive system, temperature and humidity are the most effective parameters affecting the slippage. This study is done in two stages. Firstly, experimental study has been carried out and the effect of temperature, relative humidity on the slippage between V-belt and pulley has been analyzed. At the second stage, non-linear regression analysis has been carried out to get a prediction equation for determining of friction coefficient between V-belt and pulley at the different temperature and humidity. In the analysis MATLAB Statistics Toolbox was used. At the result of the analysis the prediction equation has been obtained with 0.995 correlation coefficient. It has been seen that increase of temperature and humidity leads to decrease in the coefficient of friction (slippage raises). In high humidity conditions, slip quantity raises rapidly when temperature is 60-80°C.

IPC Code: F16H13/00

 

Indian Journal of Engineering & Materials Sciences

Vol. 13 October 2006, pp. 411-416

 

Experimental and analytical investigation of loosening and
shakedown of the threaded joints

 

Mindaugas Leonavičius, Algimantas Krenevičius, Marijonas Šukšta, Stanislav Stupak & Žilvinas Bazaras

 

In a tight threaded joint subjected to cyclic bending the regularities of crack formation and propagation possess specific features compared to joints subjected to the cyclic tension. The investigation results of tightening dependence on the number of cycles of threaded joints made of various steels show that a fatigue crack forms and propagates, plastic deformations develop or a structure element adapts oneself to a cyclic effect. In threaded joints subjected to tension and cyclic bending there is a link established between loosening and the fracturing process parameters such as the configuration and depth of crack. Due to such non-elastic deformation dangerous states may occur leading to deterioration of bolts. One of such states is characterised by a progressing accumulation of deformations resulting in the changes in the geometry of constructive elements. The approximate kinematic theorem has been used for the estimation of the bolt shakedown parameters in case of tension and bending.

IPC Code: F16L, G01N3/00

Indian Journal of Engineering & Materials Sciences

Vol. 13, October 2006, pp. 417-425

 

 

investigation of low cycle fatigue crack opening size and closure stress

 

M Daunys & A Taraškevičius

 

In the recent years, a number of studies on the fatigue crack opening and crack closure load have been carried out. Present investigation serves as an intermediate point to complete a failure prediction model with a more practical value for determination of leak before the break (LBB) problem in pressure vessels and pipes. An attempt has been made to solve this problem by using analytical, numerical and experimental methods. Method of linear fracture mechanics at analytical investigation by using the analogy between the stress strain state at stress concentrator and the crack tip and strain intensity factor is adapted to the nominal elastic-plastic loading. Investigation has showed that numerical results are in good agreement with the experimental results. However, the proposed analytical model satisfactorily matches with the experiment in the middle of the crack, which is acceptable for LBB conception, and incorrect at the crack tip, which is non-acceptable for the fracture mechanics conception.

IPC Code: G01N3/00

 

Indian Journal of Engineering & Materials Sciences

Vol. 13, October 2006, pp. 426-434

 

Influence of manganese ions on electrical, spectroscopic and magnetic properties of PbO-Al2O3-B2O3 glasses

 

M Rami Reddy, G Naga Raju & N Veeraiah

 

PbO-Al2O3-B2O3 glasses containing small concentrations of MnO (ranging from 0 to 1.0 mol%) have been prepared. A number of studies, viz., dielectric properties (constant e˘, loss tand, a.c.conductivity sac over a range of frequency and temperature), infrared, optical absorption and ESR spectra and magnetic susceptibility of these glasses have been carried out. The analysis of the results indicates that manganese ions exist mostly in Mn3+ state in these glasses when the concentration of MnO is greater than 0.5 mol% in the glass matrix.

IPC Code: C03C

 

Indian Journal of Engineering & Materials Sciences

Vol. 13, October, 2006, pp. 435-442

 

Elastic property evaluation of jute-glass fibre hybrid composite using experimental and CLT approach

K Sabeel Ahmed & S Vijayarangan

 

Elastic properties are the basic quantities that are required during design and optimization of a laminated structure. Though the literature on elastic properties of conventional single fibre composite is well published, the same is scanty in the case of natural and hybrid composites. This work is focused on evaluation of in-plane elastic properties of untreated woven jute and jute-glass fabric hybrid polyester composites, under tension. The specimens have been fabricated by hand-lay-up technique with different relative weight fraction of jute and glass fibre. Theoretically, the laminate elastic properties are predicted by using the classical lamination theory (CLT) and rule of hybrid mixture model, using the resin and fibre properties together with the volume fraction (micromechanics). Experimentally, the elastic properties have been evaluated by tension test in warp and weft direction and in-plane shear test as per ASTM standards. The results indicated that the Young’s modulus in both warp and weft direction improve by the inclusion of glass fibre, where as Poisson’s ratio is decreased. Prediction by CLT and model showed close agreement with experimental values with a maximum deviation of about 20%. The possible causes for this deviation are discussed.

IPC Code: C03C14/00, C03C17/32

 

Indian Journal of Engineering & Materials Sciences

Vol. 13, October 2006, pp. 443-450

 

Preparation of rare earth oxide doped alumina ceramics, their hardness and fracture toughness determinations

 

Kuntal Maiti & Anjan Sil

 

Alumina based ceramics doped with rare earth oxide (Y2O3) of 500 ppm, 1000 ppm and 2000 ppm were prepared by following ceramic powder processing and solid state sintering at 1500°C for different soaking time periods of 3 h, 6 h and 9 h. Microstructural investigations on all the samples were carried out. Hardness measurements were conducted using Vickers Indentation technique. Fracture toughness of the samples was estimated by inducing radial cracks by various indentation loads on the samples. The measured hardness values were found to lie between 139 MPa and 1444 MPa, while the fracture toughness values lie in the range 1.65-5.76 MPa m1/2.

IPC Code: C04B35/40

 

Indian Journal of Engineering & Materials Sciences

Vol. 13, October 2006, pp. 451-454

 

A modified gun technique for melt quenching of reactive alloys

V Venkateswara Rao

 

The conventional gun melt quenching technique was slightly modified to facilitate rapid solidification of highly reactive alloys like Cu-Mg. This involved the use of molten salt flux for melting and quenching the alloy. The cooling rate achieved was estimated to be in the range of 105-106 K/s. A Cu-28 at% Mg alloy was successfully melt-quenched by this method. The melt-quenched foils had a lustrous golden yellow colour. Formation of metastable tetragonal and amorphous phases was determined by XRD and TEM.

IPC Code: C22C 9/05

 

Indian Journal of Engineering & Materials Sciences

Vol. 13, October 2006, pp. 455-461

 

Ionic transport in sodium phosphate glasses doped with chlorides of
Co, Cd and Ag

 

S S Das, Vibha Srivastava & P Singh

 

Several samples of sodium phosphate glasses doped with different concentrations of chlorides of cadmium and cobalt along with samples of undoped sodium phosphate glass have been prepared. Sodium phosphate glasses doped with varying amounts of AgCl have also been prepared to see the role of Ag+ ion in modifying the conductivity of sodium phosphate glass. These glasses have been characterized by elemental analysis, X-ray diffraction, IR spectra, differential scanning calorimetry, transference number measurements and electrical conductivity studies. All the glasses are found to be essentially ionic conductors. The undoped sodium phosphate glass has low s value in comparison to the doped ones. The values of ionic conductivity in Na2O‑P2O5‑CdCl2 and Na2O-P2O5-CoCl2 glasses are maximum for 1% CdCl2 and 5% CoCl2 doped ones respectively. However, in the case of Na2O-P2O5-AgCl glass the s values go on increasing with the increasing concentrations of the dopant AgCl and the following sequence is observed.

s (-CdCl2) < s (-CoCl2) < s (-AgCl)

These results have been explained on the basis of changes in the structure of sodium phosphate glass matrix by the addition of different dopant cations, viz; Cd2+, Co2+ and Ag+.

IPC Code: C03C4/18

 

Indian Journal of Engineering & Materials Sciences

Vol. 13, October 2006, pp. 462-466

 

Studies on energetic compounds Part 42 — Thermolysis of
5-amino-3-nitro-1,2,4-triazole (ANTA)

 

G Singh, C P Singh, J PAgrawal & A K Sikder

 

The thermolysis of 3-amino-5-nitro-1,2,4-triazole (ANTA) has been undertaken using thermogravimetry-differential thermal analysis (TG-DTG-DTA) and differential scanning calorimetry (DSC) techniques in N2 atmosphere. TG and DTA have also been done separately in air to examine the effect of atmospheric changes. Isothermal TG has been done upto mass loss of 36% and data there from has been used to evaluate kinetic parameters using model fitting as well as model free isoconversional method. Rapid thermolysis of the sample has been studied by measuring explosion delay and evaluating its kinetic parameters. The first step in ANTA thermolysis involves removal of NO2 followed by ring rupture leading to the formation of gaseous products such as CO2, N2O, HCN and HNCO.

IPC Code: C06B

 

Indian Journal of Engineering & Materials Sciences

Vol. 13, October 2006, pp. 467-470

 

Corrosion fatigue of welded joints of steel for marine platform

 

Yantao Li  & Baorong Hou

 

Experiments on the corrosion fatigue behaviour of welded joints of the steel for marine platform in air and seawater, and of the joints in seawater with cathodic protection, yielded data for linear regression to obtain fatigue life curves (ΔS-Nf). The laws of corrosion fatigue in welded joints of test steel are discussed with reference to those of A587 and A131 steel. In these experiments, the fatigue damage occurring at all welded joints around the weld interface resulted in the cracks and fractures. The fatigue life of the specimens in seawater with cathodic protection is longer than that in seawater without protection.

IPC Code: G01N3/00, G01N17/00