Hostname: page-component-76fb5796d-5g6vh Total loading time: 0 Render date: 2024-04-26T03:42:26.169Z Has data issue: false hasContentIssue false
  • English
  • Français

On sinterability of nanostructured W produced by high-energy ball milling

Published online by Cambridge University Press:  03 March 2011

R. Malewar ,
K.S. Kumar ,
B.S. Murty ,
B. Sarma  and
S.K. Pabi
R. Malewar
Affiliation:
Defense Metallurgical Research Laboratory, Hyderabad, India
K.S. Kumar
Affiliation:
Department of Metallurgical and Materials Engineering, Indian Institute of Technology, Kharagpur 721302, India
B.S. Murty
Affiliation:
Department of Metallurgical and Materials Engineering, Indian Institute of Technology, Madras, Chennai 600036, India
B. Sarma
Affiliation:
Defense Metallurgical Research Laboratory, Hyderabad, India
S.K. Pabi*
Affiliation:
Department of Metallurgical and Materials Engineering, Indian Institute of Technology, Kharagpur 721302, India
*
a) Address all correspondence to this author. e-mail: skpabi@metal.iitkgp.ernet.in
Get access

Abstract

The present investigation reports for the first time a dramatic decrease in the sintering temperature of elemental W from the conventional temperature of ≥2500 °C to the modest temperature range of 1700–1790 °C by making the W powder nanostructured through high-energy mechanical milling (MM) prior to sintering. The crystallite size of the initial W powder charge with a particle size of 3–4 μm could be brought down to 8 nm by MM for 5 h in WC grinding media. Further milling resulted in a high level of WC contamination, which apparently was due to work hardening and the grain refinement of W. A sintered density as high as 97.4% was achieved by sintering cold, isostatically pressed nanocrystalline (8 nm) W powder at 1790 °C for 900 min. The microstructure of the sintered rods showed the presence of deformation bands, but no cracks, within a large number of W grains. The mechanical properties, when compared with the hardness and elastic modulus, of the sintered nano-W specimen were somewhat superior to those reported for the conventional sintered W.

Keywords

NanostructureSinteringW
Type
Articles
Information
Journal of Materials Research , Volume 22 , Issue 5 , May 2007 , pp. 1200 - 1206
Copyright
Copyright © Materials Research Society 2007

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1Smith, W.F.: Structure and Properties of Engineering Alloys 2nd ed. (McGraw Hill, New York, NY, 1993), pp. 580–586.Google Scholar
2Trazaska, M.: Correlation between the temperature distribution and the structure of resistance sintered tungsten bars. Int. J. Refract. Met. Hard Mater. 14, 235 (1996).CrossRefGoogle Scholar
3Uray, L.: AKS doped tungsten investigated by electrical resistivity: I. Manufacturing tungsten bar and wire. Int. J. Refract. Met. Hard Mater. 20, 311 (2002).CrossRefGoogle Scholar
4Uray, L.: AKS doped tungsten wire investigated by electrical measurements: II. Impurities in tungsten. Int. J. Refract. Met. Hard Mater. 20, 319 (2002).CrossRefGoogle Scholar
5Grüger, A., Vassen, R., and Mertens, F.: The evaporation of potassium during sintering of doped tungsten. Int. J. Refract. Met. Hard Mater. 16, 37 (1998).CrossRefGoogle Scholar
6Kolczynski, Z., Rutkowski, W., Swierczynska, M.B., and Trzanska, M.: Structure of sintered tungsten bars as effect of processing load. Powder Metall. Int. 20, 22 (1988).Google Scholar
7Pink, E. and Bartha, L.: The Metallurgy of Doped/Non-Sag Tungsten (Elsevier, New York, NY, 1989), pp. 127–135.Google Scholar
8Trzaska, M.: Influence of technological parameters on the structure of tungsten sintered bars. Inz. Materialowa 65, 139 (1991).Google Scholar
9Rabe, T. and Wäsche, R.: Sintering behaviour of nanocrystalline titanium nitride powders. Nanostruct. Mater. 6, 357 (1995).CrossRefGoogle Scholar
10Pechenik, A., Piermarini, G.J., and Danforth, S.C.: Fabrication of transparent silicon nitride from nanosize particles. J. Am. Ceram. Soc. 75, 3283 (1992).CrossRefGoogle Scholar
11Hahn, H.: Microstructure and properties of nanostructured oxides. Nanostruct. Mater. 2, 251 (1993).CrossRefGoogle Scholar
12Averbach, R.S., Zhu, H., Tao, R., and Hofler, H.J.: Sintering of nanocrystalline materials: experiments and computer simulations, in Synthesis and Processing of Nanocrystalline Powder edited by Bourell, D.L. (TMS, Warrendale, PA 1996), pp. 203–216.Google Scholar
13Bourell, L. and Groza, J.R.: Consolidation of ultra fine and nanocrystalline powder, in ASM Handbook 7 (American Society of Metals, Metals Park, OH, 1998), pp. 583–589.Google Scholar
14Groza, J.R.: Sintering of nanocrystalline powders. Int. J. Powder Metall. 35, 59 (1999).Google Scholar
15Groza, J.R.: Nanocrystalline powder consolidation methods, in Nanostructured Materials-Processing, Properties and Potential Applications, edited by Koch, C.C. (Noyes, New York, NY, 2002), pp. 115–178.Google Scholar
16Ricceri, R. and Matteazzi, P.: A study of formation of nanometric W by room temperature mechanosynthesis. J. Alloys Compd. 358, 71 (2003).CrossRefGoogle Scholar
17Cullity, B.D.: Elements of X-Ray Diffraction 2nd edition (Addison Wesley, Reading, MA, 1978), pp. 350–368, 411–415.Google Scholar
18Suryanarayana, C.: Mechanical alloying and milling. Prog. Mater. Sci. 46, 1 (2001).CrossRefGoogle Scholar
19Lönnberg, B.: Characterization of milled Si3N4 powder using x-ray peak broadening and surface area analysis. J. Mater. Sci. 29, 3224 (1994).CrossRefGoogle Scholar
20Pabi, S.K. and Murty, B.S.: Mechanism of mechanical alloying in Ni-Al and Cu-Zn systems. Mater. Sci. Eng., A 214, 146 (1996).CrossRefGoogle Scholar
21Fecht, H-J.: Thermodynamic properties and stability of grain boundaries in metals based on the universal equation of state at negative pressure. Acta Metall. Mater. 38, 1927 (1990).CrossRefGoogle Scholar
22Pabi, S.K., Joardar, J., and Murty, B.S.: Formation of nanocrystalline phases in Cu-Zn system during mechanical alloying. J. Mater. Sci. 31, 3207 (1996).CrossRefGoogle Scholar
23Pabi, S.K., Joardar, J., Manna, I., and Murty, B.S.: Nanocrystalline phases in Cu-Ni, Cu-Zn and Ni-Al systems by mechanical alloying. Nanostruct. Mater. 9, 149 (1997).CrossRefGoogle Scholar
24Koch, C.C.: The synthesis and structure of nanocrystalline materials produced by mechanical attrition: A review. Nanostruct. Mater. 2, 109 (1993).CrossRefGoogle Scholar
25Chattopadhyay, P.P., Pabi, S.K., and Manna, I.: An allotropic transformation in Nb induced by planetary ball milling. Mater. Sci. Eng., A 304–306, 424 (2001).CrossRefGoogle Scholar
26Chattopadhyay, P.P., Nambissan, P.M.G., Pabi, S.K., and Manna, I.: Polymorphic transformation and lattice expansion in nanocrystalline niobium revealed by positron annihilation. Appl. Surf. Sci. 182, 308 (2001).CrossRefGoogle Scholar
27Chattopadhyay, P.P., Nambission, P.M.G., Pabi, S.K., and Manna, I.: Polymorphic bcc to fcc transformation of nanocrystalline niobium studied by positron annihilation. Phys. Rev. B: Condens. Matter 63, 54107 (2001).CrossRefGoogle Scholar
28Chatterjee, P.P., Pabi, S.K., and Manna, I.: An allotropic transformation induced by mechanical alloying. J. Appl. Phys. 86, 5912 (1999).CrossRefGoogle Scholar
29Datta, M.K., Pabi, S.K., and Murty, B.S.: Phase fields in nickel silicides obtained by mechanical alloying. J. Appl. Phys. 87, 8393 (2000).CrossRefGoogle Scholar
30Berger, S., Porat, R., and Rosen, R.: Nanocrystalline materials: A study of WC-based hard metals. Prog. Mater. Sci. 42, 311 (1997).CrossRefGoogle Scholar
31Brunner, D.: Peculiarities of work hardening of high-purity tungsten single crystals below 800 K. Mater. Sci. Eng., A 387–389, 167 (2004).CrossRefGoogle Scholar
32Zhu, H. and Averbech, R.S.: Sintering processes of two nanoparticles: A study by molecular dynamics simulations. Philos. Mag. Lett. 73, 27 (1996).CrossRefGoogle Scholar