Journal of Materials Sciences and Applications

2015; 1(4): 168-173

Published online July 30, 2015 (http://www.aascit.org/journal/jmsa)

Keywords Lead Borate,

Mechanical Alloying,

Nanocrystalline,

Amorphization

Received: June 30, 2015

Revised: July 16, 2015

Accepted: July 17, 2015

Structural Analysis of PbO-B2O3-ZnO Glasses by High Energy Ball Milling (Attritor)

Abd-Elmoneim M. Shamah1, Ahmed E. Hannora

1, *,

Hesham A. Yousef2, Mai M. Gad

1

1Science and Mathematics Department, Faculty of Petroleum and Mining Engineering, Suez

University, Suez, Egypt 2Physics Department, Faculty of Science, Suez University, Suez, Egypt

Email address ahmed.hannora@suezuniv.edu.eg (A. E. Hannora)

Citation Abd-Elmoneim M. Shamah, Ahmed E. Hannora, Hesham A. Yousef, Mai M. Gad. Structural

Analysis of PbO-B2O3-ZnO Glasses by High Energy Ball Milling (Attritor). Journal of Materials

Sciences and Applications. Vol. 1, No. 4, 2015, pp. 168-173.

Abstract Lead, boron and zinc oxides powder were subjected to the mechanical milling/alloying to

study the structural transformation. The process was carried out at room temperature in a

high energy ball milling (attritor). The compositional effects on the amorphization process

of the ball-milled were investigated. The X-ray Diffraction (XRD) and Fourier transform

infrared spectroscopy (FT-IR) results indicated that zinc oxide was the residual phase after

10 hours of mechanical milling. The compositions play a significant role in powder

morphology. The FT-IR sharp peaks are completely disappeared with higher lead oxide

concentration. The formed glasses consist of chains of ortho- and penta- borate groups.

1. Introduction

Borate glasses have been used as electro-optic switches, electro-optic modulators,

non-linear parametric converters and solid state laser materials by incorporating with

heavy metal oxides. All these properties have some effect with respect to the dielectric

properties of the medium. Therefore studies of dielectric properties have also got some

interests [1]. Lead oxide has many extraordinary properties such as high refractive index,

large density, high non-linear optical susceptibility and excellent infrared transmission.

Moreover the high density of this glass makes it a candidate for radiation shielding

material [2]. Although it is not a glass-forming oxide by itself, it can be incorporated in

substantial quantities into the other glass-forming oxide systems such as SiO2, B2O3 and

P2O5 [3]. PbO is known to enter PbO–B2O3 glasses as only a modifier oxide up to 15 mol%.

In this case PbO is entirely consumed to convert triangular BO3 units into BO4 tetrahedra.

Above 15–20 mol% PbO some lead atoms start to be network former in the form of PbO4

units. The fraction of PbO4 units undergoes a monotonic increase when increasing the

PbO content up to the glass formation limit. On the other hand, there is an increase in the

concentration of BO4 units and thus in the fraction N4 of four coordinated boron atoms up

to a maximum around 50mol% PbO [4].

B2O3-based glasses are an important material for the insulation and textile fiberglass.

Lead borate oxide glasses are highly transparent in the visible and near infrared regions.

Moreover the ZnO-B2O3-PbO glasses have the desired characteristics against irradiation

since the naturally occurring stable boron isotope is a good absorber of thermal neutrons

and lead is known as a shielding material of gamma rays [5]. It is now well known that

lead oxide (PbO) is unique in its influence on the glass structure and is widely used in

169 Abd-Elmoneim M. Shamah et al.: Structural Analysis of PbO-B2O3-ZnO Glasses by High Energy Ball Milling (Attritor)

glasses because it enhances the resistance against

devitrification, improves the chemical durability and lowers

the melting temperature [6].

Mechanical milling/alloying (MM/MA) is a potential

method for the preparation of various interesting solid-state

materials and takes advantage of the perturbation of

surface-bonded species by pressure to enhance

thermodynamic and kinetic reactions between solids. Over the

past decades, MM/MA has been widely developed for the

fabrication of a wide range of advanced materials such as

supersaturated solid solutions, metastable crystalline and

quasicrystalline phases, nanostructures, amorphous alloys or

ceramic materials and intermetallics. Mechanical

alloying/milling is a solid state powder processing technique

involving cold-welding and fracturing of powder particles.

The constituent powder particles are repeatedly fractured and

cold welded, so that powder particles with very fine structure

can be obtained after milling [7] [8].

Until now, to the best of our knowledge, no detailed

investigation has been carried out dealing with the effects of

the synthesis parameters on the structure of lead borate zinc by

mechanical alloying method. So the purpose of the present

work is to study the effect of mechanical milling/alloying on

the lead borate zinc with varying compositions.

2. Materials and Samples

Zinc oxide 99.9%, Boron oxide 99% and Lead (ll) oxide

99.9% -325 mesh powders (Alfa Asar) were placed into 600

cm3 high energy ball milling attritor, rotating with 500 RPM.

The powders were treated with hard steel balls at different

milling times with the optimum balls to powder ratio equals to

20:1. The detailed compositions of the samples used in the

present study are as follow, table 1;

Table 1. Chemical composition of the studied samples.

Sample code PbO B2O3 ZnO

PBZ 1 20 70 10

PBZ 2 30 60 10

PBZ 3 40 50 10

PBZ 4 50 40 10

PBZ 5 60 30 10

PBZ 6 70 20 10

XRD was performed using D5000 powder diffractometer

using Cu Kα radiation (wavelength λ = 0.15406 nm) with a

nickel filter at 40 kV and 30 mA. The diffractometer was

operated within range of 20° < 2θ < 60° with step-time = 1

seconds and step-size = 0.05 degree. Diffraction signal

intensity throughout the scan was monitored and processed

with DIFFRACplus software. Topas 2.1 Profile fit software

was used to extract the peak parameters and the Pseudo Voigt

function was used to model the peak shape. The as-received

lead oxide was matched with ICDD (JCPDS) standard cards,

(65-0129) orthorhombic phase with space group Pbcm(57)

and (85-1289) tetragonal phase with space group

P4/nmm(129). The zinc oxide powder was matched with card

number 65-4311, while as-starting boron oxide was in

amorphous state, figure 1.

Fig. 1. X-ray diffraction patterns of the starting ZnO, PbO and B2O3 powder.

The morphology of the samples was investigated by using

Scanning Electron Microscope (SEM) Model Quanta 250

FEG (Field Emission Gun).

3. Results and Discussion

The nature of the crystalline phases and the microstructure

of the materials are the most important factors affecting its

technical properties. Figure 2 presents the X-ray diffraction

patterns of ball milled PBZ4 powder mixture. The mixture

was milled for different periods up to10 hrs. The XRD pattern

of the as received powder shows only sharp peaks

corresponding to the starting materials mixture; a mixture of

different crystalline structures, two allotropic structures of

Journal of Materials Sciences and Applications 2015; 1(4): 168-173 170

lead oxide and zinc oxide ICDD (JCPDS) (65-0129; 85-1289

and 65-4311) and a non-crystalline B2O3 were found as

expected. As shown, after 30 minutes of high energy ball

milling the lead oxide peaks shows a notable intensity

reduction as a result of severe plastic deformation. The

diffraction of (111) peak for orthorhombic PbO (29.08° of 2θ)

dramatically decreases, whereas the tetragonal α-PbO

structure and zinc oxide phase stile stable. After ten hours of

MM/MA all lead oxide peaks were disappeared and only zinc

oxide phase was found. No additional new phases were

detected throughout the MM/MA process up to ten hours.

Fig. 2. X-ray diffraction patterns of the mechanical milling PBZ4 sample.

Fig. 3. X-ray diffraction patterns of the 10 hours mechanically milled sample.

The average grain size and the internal strain of lead oxide

were calculated from the XRD patterns by the

Hall–Williamson method [9]. After two hours of milling the

crystallite size and micro-strain was 129.4 nm and 0.0549,

while the five hours milled sample was 64.7 nm and 0.0516

respectively. The excessive cold working of the powder

during mechanical milling leads to the formation of high

density of defects that could hold responsible for the observed

high strain in the sample.

According to XRD patterns shown in figure 3, increasing

lead oxide content more than 40wt.%, up to PBZ3, a complete

disappearance of all peaks related to lead oxide phases. As

shown in XRD patterns, all higher lead oxide content

contained the evidence of ZnO nanocrystalline peaks

superimposed onto a broad amorphous background. Although

continued milling could change the amounts of amorphous

phases, this paper will focus on the comparison between the

effects of different compositions after 10 hrs of ball milling.

Although the same amount of ZnO was added, the crystalline

peaks were of different intensities for the different

compositions, indicating that there were different amounts of

amorphous phase present in each composition.

171 Abd-Elmoneim M. Shamah et al.: Structural Analysis of PbO-B2O3-ZnO Glasses by High Energy Ball Milling (Attritor)

As reported in [10], the amorphization process starts when

the powders have experienced a certain number of critical

loading events which depends on the impact energy. The

unusual reactivity observed has been ascribed to the

far-from-equilibrium working conditions, resulting in severe

plastic deformations and local excited states. After ten hours

of MM/MA the XRD pattern shows the partially amorphous

nature of the samples. Increasing milling energy could

produce a complete amorphous phase [7] [11]. It is reported

that [12], lead borate glasses have a low melting temperatures

and wide glass formation region, while zinc oxide shows a

higher melting point temperature. This could be the main

factor that affecting amorphization process due to impact

energy. Also, the free energy due to lattice deformation plays a

significant role in glass formability.

Fig. 4. Optical image of the starting powder (a) B2O3, (b) PbO (c) ZnO and (d)10 hours mechanical milling sample.

Figure 4 shows the macrostructure of the samples,

indicating the colour change associated with 10 hours of

mechanical milling. The morphology of the samples was

investigated by SEM to reveal the particle size details and the

morphological changes after mechanical milling. SEM

micrograph of PBZ1 sample consists of laminar or plate like

structure, fig. 5a. With increasing lead oxide content the

laminar structure decreases and nearly not found with PBZ3.

The PBZ4 and PBZ5 powder particles were fine irregular in

shape with different sizes. Due to cold welding of the milled

powder during mechanical milling, the large agglomerates are

composed of several smaller grains. Sample PBZ6 shows fine

particles and fibre like structure due to local melting through

the mechanical milling\alloying process.

Journal of Materials Sciences and Applications 2015; 1(4): 168-173 172

Fig. 5. SEM micrographs of the 10 hours milled samples.

Glasses containing heavy metal oxide have attracted the

attention of several workers in recent years for their excellent

infrared transmission compared with conventional glasses

[13]. Figure 6 shows infrared transmission spectra in the 400 –

4000 cm-1

region of 10 hours mechanically milled powder. It

is clear from figure 6 that, spectra of PBZ1 and PBZ2

specimens are nearly similar, having broad bands around

3700-2800 and 1600-1300 while at 700-870 cm-1

range two

bands overlapped. Sharp intense bands was observed at 2262,

1193, 646 and 547 cm-1

. Weak bands found at, 2513, 2360 and

883 cm-1

. For the PBZ3 sample, weak bands nearly

disappeared and the intensity sharper decreases. With PBZ4 to

PBZ6, weak band was observed at 1638 cm-1

while other

bands nearly disappear.

It is reported that [6] [14] [15], three domains could be

separated in the infrared spectra of the borate glasses: the

absorption wave number profile in 400 - 800 cm-1

range is

assigned to the bending vibrations of various borate segments,

PbO bond vibrations; the medium absorption placed between

800 and 1200 cm-1

is due to the B-O asymmetric stretching of

tetrahedral BO4 units; strong absorption bands that appeared

in the 1200 - 1600 cm-1

range are generated by the stretching

vibrations of borate units in which boron atoms are connected

to three oxygen (BO3 units). While [12] shows that, broad

band between 1300 and 1600 cm-1

attributed to the stretching

vibration of B–O–B in [BO3] triangles. Also, transmission

peak around 1050 cm-1

causes one boron to change from the

B3 state to B4 state. With higher content of PbO, the lead ions

acting as glass-forming agent and a band around 470 cm has

been observed due to PbO4 vibrations [2] [14]. The absorption

band at 470-530 cm-1

is stretching mode of ZnO.

Fig. 6. FT-IR patterns of the 10 hours mechanically milled sample.

173 Abd-Elmoneim M. Shamah et al.: Structural Analysis of PbO-B2O3-ZnO Glasses by High Energy Ball Milling (Attritor)

As shown in figure 6, the relative areas of the observed

bands were increased with increasing milling time up to 6

hours. It is reported that [2], as the relative area of the 470 cm-1

peak increase, the stretching force of Pb–O bond tend to

decrease. So, the bond length of Pb–O increases and may

increase the molar volume as a result. The observed infrared

transmission peak at 3216 cm-1

region of the glass containing

metal oxides replacing parts of sodium oxide is due to the

strong hydrogen bonded OH stretching vibrations, and the

peak region 1620 cm is due to the H2O [2] [16]. The

near-infrared bands in the region 3000–4000 cm-1

are related

to vibrations of water, OH or B-OH groups. It is reported that

[17] [15], the broad bands are exhibited in the oxide spectra,

most probably due to the combination of high degeneracy of

vibrational states, thermal broadening of the lattice dispersion

band and mechanical scattering from powder samples.

It is reported that [18], Infrared absorptions are not infinitely

narrow and there are several factors that contribute to the

broadening. The collision between molecules is a factor. There

is also the broadening of bands due to lifetime of the states

involved in the transition. From quantum mechanics, the energy

states of the system do not have precisely defined energies and

this leads to lifetime broadening. There is a relationship

between the lifetime of an excited state and the bandwidth of

the absorption band associated with the transition to the excited

state, and this is a consequence of the Heisenberg Uncertainty

Principle. This relationship demonstrates that the shorter the

lifetime of a state, then the less well defined is its energy.

4. Conclusion

� It is possible to obtain nanocrystalline/amorphous phases

at room temperature of lead, boron and zinc oxides

powders by mechanical alloying.

� Infrared spectroscopy data shows both triangular and

tetrahedral borate groups at all compositions.

� With higher lead oxide content PbO4 vibrational band

was observed at ~470 cm-1

.

� The morphology of milled powder with 20 to 40 wt.%

lead oxide content, was composed of laminar structure

while fine particles and large agglomerates were

observed with 50 and 60 wt.% PbO samples.

� Fiber like structure was formed after mechanical

milling/alloying with 70wt.% lead oxide content.

References

[1] S.l Thomas, Sk. Rasool, M. Rathaiah, V. Venkatramu, C. Joseph, N.V. Unnikrishnan. Spectroscopic and dielectric studies of Sm3+ ions in lithium zinc borate glasses. Journal of Non-Crystalline Solids, 376 (2013), 106–116.

[2] K. El-Egili, H. Doweidar, Y.M. Moustafa, I. Abbas. Structure and some physical properties of PbO–P2O5 glasses. Physica B, 339 (2003), 237–245.

[3] P. Limkitjaroenporn, J.Kaewkhao, P.Limsuwan, W.Chewpraditkul. Physical, optical, structural and gamma-ray

shielding properties of lead sodium borate glasses. Journal of Physics and Chemistry of Solids, 72 (2011), 245–251.

[4] H. Doweidar, G. El-Damrawi, E. Mansour, R.E. Fetouh. Structural role of MgO and PbO in MgO–PbO–B2O3 glasses as revealed by FTIR; a new approach. Journal of Non-Crystalline Solids, 358 (2012), 941–946.

[5] H. Singh, K. Singh, L. Gerward, K. Singh, H. Sahota, R. Nathuram. ZnO–PbO–B2O3 glasses as gamma-ray shielding materials. Nuclear Instruments and Methods in Physics Research, B 207 (2003), 257–262.

[6] R. Lucacel, C. Marcus, V. Timar, I. Ardelean. FT-IR and Raman spectroscopic studies on B2O3-PbO-Ag2O glasses dopped with manganese ions. Solid State Sciences, 9 (2007), 850-854.

[7] B.Stuart. Infrared Spectroscopy: Fundamentals and Applications. John Wiley & Sons, Ltd, 2004.

[8] C.Suryanarayana. Mechanical alloying and milling. Progress in Materials Science, 46, 1-2 (2001), 1-184.

[9] E. Furlani, E. Aneggi, C. de Leitenburg, S. Maschio. High energy ball milling of titania and titania–ceria powder mixtures. Powder Technology, 254 (2014), 591–596.

[10] Klung H P, Alexander E. X-ray diffraction procedures for polycrystalline and amorphous materials. John Wiley, New York, 1974.

[11] F. Delogu, G. Cocco. Kinetics of amorphization processes by mechanical alloying: A modeling approach. Journal of Alloys and Compounds, 436 (2007), 233–240.

[12] B. S. Murty, M. Mohan Rao and S. Ranganathan. Milling Maps and Amorphization During Mechanical Alloying. Aclo metall. mater., 43, 6 (1995), 2443-2450.

[13] Y. Cheng, H. Xiao, W. Guo, W. Guo. Structure and crystallization kinetics of PbO–B2O3 glasses. Ceramics International, 33 (2007), 1341–1347.

[14] S. Baccaro, Monika, G. Sharma, K.S. Thind, D.P. Singh. Variation of optical band gap with radiation dose in PbO–B2O3 glasses. Nuclear Instruments and Methods in Physics Research, B 266 (2008), 594–598.

[15] P. Ramesh Babu, R. Vijay, P. Srinivasa Rao, P. Suresh, N. Veeraiah, D. Krishna Rao. Dielectric and Spectroscopic properties of CuO doped multi-component Li2O-PbO-B2O3-SiO2-Bi2O3-Al2O3 glass system. Journal of Non-Crystalline Solids, 370 (2013), 21–30.

[16] S. G. Motke, S. P. Yawale and S. S. Yawale. Infrared spectra of zinc doped lead borate glasses. Bull. Mater. Sci., 25, 1 (2002), 75–78.

[17] S. Ibrahim, M. Gomaa, H. Darwish. Influence of Fe2O3 on the physical, structural and electrical properties of sodium lead borate glasses. Journal of Advanced Ceramics, 3, 2 (2014), 155–164.

[18] H.A. ElBatal, A.M. Abdelghany, F.H. ElBatal, F.M. EzzElDin. Gamma rays interactions with WO3-doped lead borate glasses. Materials Chemistry and Physics, 134 (2012), 542– 548.