Fabrication of full-density W-brass composites is very difficult to achieve because of evaporation
of zinc, insolubility of W and brass and compacts expansion. In this study, to achieve full-density
W-brass composites, mechanical alloying (MA) and activated sintering process were utilized. Mechanical
coating of W with Ni using high energy planetary ball mill was carried out. The milling
was divided into two stages: to alloy and modify the surface of W with Ni for enhanced activation.
The microstructure of the milled powders and sintered compacts, elemental composition and
phases present were studied by using scanning electron microscopy (SEM), energy dispersive
X-ray spectroscopy (EDX) and X-ray diffraction (XRD) respectively. As-received powder compacts
was also sintered under the same condition for comparison purpose. The effects of milling time on
the microstructure, sinterability and the hardness of the composites were investigated. It was observed
that the samples produced from 8 h milled powder had the highest relative sintered density
(98% TD) and microhardness (234 Hv). On the other hand, the samples from the as-received
powders expanded and had a relative sintered density of (67% TD) and microhardness as low as
24 Hv. The significance of this study is the possibility of producing W-brass composites as a
cheaper alternative to W-Cu composites.
References
[1]
Huang, L.-M., Luo, L.-M., Ding, X.-Y., Luo, G.-N., Zan , X., Cheng, J.-G. and Wu, Y.-C. (2014) Effects of Simplified Pretreatment Process on the Morphology of W-Cu Composite Powder Prepared by Electroless Plating and Its Sintering Characterization. Powder Technology, 258, 216-221. http://dx.doi.org/10.1016/j.powtec.2014.03.027
[2]
Gowon, B., Mohammed, K.S., Jamaluddin, S.B., Hussain, Z., Aminu, A.D. and Lawal, Y.A. (2015) Experimental Studies on the Effects of Tin on the Densification of W-Brass Composites. Applied Mechanics and Materials, 754-755, 838-843.
[3]
Mohammed, K.S., Rahmat, A. and Aziz, A. (2013) Self-Compacting High Density Tungsten-Bronze Composites. Journal of Materials Processing Technology, 213, 1088-1094. http://dx.doi.org/10.1016/j.jmatprotec.2013.02.006
[4]
Luo, L.-M., Tan, X.-Y., Lu, Z.-L., Zhu, X.-Y., Zan, X., Luo, G.-N., et al. (2014) Sintering Behavior of W-30Cu Composite Powder Prepared by Electroless Plating. International Journal of Refractory Metals and Hard Materials, 42, 51-56. http://dx.doi.org/10.1016/j.ijrmhm.2013.10.012
[5]
Ho, P.W., Li, Q.F. and Fuh, J.Y.H. (2008) Evaluation of W-Cu Metal Matrix Composites Produced by Powder Injection Molding and Liquid Infiltration. Materials Science and Engineering: A, 485, 657-663. http://dx.doi.org/10.1016/j.msea.2007.10.048
[6]
Ardestani, M., Rezaie, H.R., Arabi, H. and Razavizadeh, H. (2009) The Effect of Sintering Temperature on Densification of Nanoscale Dispersed W-20-40%wt Cu Composite Powders. International Journal of Refractory Metals and Hard Materials, 27, 862-867. http://dx.doi.org/10.1016/j.ijrmhm.2009.04.004
[7]
Amirjan, M., Zangeneh-Madar, K. and Parvin, N. (2009) Evaluation of Microstructure and Contiguity of W/Cu Composites Prepared by Coated Tungsten Powders. International Journal of Refractory Metals and Hard Materials, 27, 729-733. http://dx.doi.org/10.1016/j.ijrmhm.2008.12.008
[8]
Ozkal, B., Upadhyaya, A., Ovecolu, M.L. and German, R.M. (2004) Realtime Sintering Observations in W-Cu system: Accelerated Rearrangement Densification via Copper Coated Tungsten Powders Approach. European Powder Metallurgy, 40, 1-6.
[9]
Abu-Oqail, A., Ghanim, M., El-Sheikh, M. and El-Nikhaily, A. (2012) Effects of Processing Parameters of Tungsten- Copper Composites. International Journal of Refractory Metals and Hard Materials, 35, 207-212. http://dx.doi.org/10.1016/j.ijrmhm.2012.02.015
[10]
Hamidi, A.G., Arabi, H. and Rastegari, S. (2011) Tungsten-Copper Composite Production by Activated Sintering and Infiltration. International Journal of Refractory Metals and Hard Materials, 29, 538-541. http://dx.doi.org/10.1016/j.ijrmhm.2011.03.009
[11]
Teodorovich, O. and Levchenko, G. (1964) Nickel in Tungsten-Copper Contacts. Soviet Powder Metallurgy and Metal Ceramics, 3, 476-479. http://dx.doi.org/10.1007/BF01194585
[12]
German, R.M. (1996) Sintering Theory and Practice. Wiley-VCH, Weinheim, 568.
[13]
El-Eskandarany, M.S. (2001) Mechanical Alloying for Fabrication of Advanced Engineering Materials. William Andrew Publishing/Noyes, New York.
[14]
Buschow, K.H.J., Cahn, R.W., Flemings, M.C., Ilschner, B., Kramer, E.J. and Mahajan, S. (2001) Mechanical Alloying. In: Buschow, K.H.J., Cahn, R.W., Flemings, M.C., Ilschner, B., Kramer, E.J. and Mahajan, S., Eds., Encyclopedia of Materials—Science and Technology, Volumes 1-11, Elsevier, Amsterdam, 5230-5246.
[15]
Suryanarayana, C. (2001) Mechanical Alloying and Milling. Progress in Materials Science, 46, 1-184. http://dx.doi.org/10.1016/S0079-6425(99)00010-9
[16]
Meng, Y.F., Shen, Y.F., Chen, C., Li, Y.C. and Feng, X.M. (2014) Effects of Cu Content and Mechanical Alloying Parameters on the Preparation of W-Cu Composite Coatings on Copper Substrate. Journal of Alloys and Compounds, 585, 368-375. http://dx.doi.org/10.1016/j.jallcom.2013.09.100
[17]
Yusoff, M. and Hussain, Z. (2013) Effect of Sintering Parameters on Microstructure and Properties of Mechanically Alloyed Copper-Tungsten Carbide Composite. International Journal of Materials, Mechanics and Manufacturing, 1, 283-286.
[18]
Alam, S.N. (2006) Synthesis and Characterization of W-Cu Nanocomposites Developed by Mechanical Alloying. Materials Science and Engineering: A, 433, 161-168. http://dx.doi.org/10.1016/j.msea.2006.06.049
[19]
Kim, J.-C. and Moon, I.-H. (1998) Sintering of Nanostructured W-Cu Alloys Prepared by Mechanical Alloying. Nanostructured Materials, 10, 283-290. http://dx.doi.org/10.1016/S0965-9773(98)00065-8
[20]
Maneshian, M.H. and Simchi, A. (2008) Solid State and Liquid Phase Sintering of Mechanically Activated W-20 wt.% Cu powder Mixture. Journal of Alloys and Compounds, 463, 153-159. http://dx.doi.org/10.1016/j.jallcom.2007.08.080
[21]
Tsakiris, V., Lungu, M., Enescu, E., Pavelescu, D., Dumitrescu, Gh., Radulian, A. and Mocioi, N. (2014) Nanostructured W-Cu Electrical Contact Materials Processed by Hot Isostatic Pressing. Acta Physica Polonica A, 125, 348-352. http://dx.doi.org/10.12693/APhysPolA.125.348
[22]
Shi, X., Yang, H. and Duan, X. (2008) Microstructure and Properties of W-15Cu Alloys Prepared by Mechanical Alloying and Spark Plasma Sintering Process. Journal of Wuhan University of Technology (Materials Science Edition), 23, 399-402.
[23]
Kecskes, L.J., Klotz, B.R., Cho, K.C., Dowding, R.J. and Trexler, M.D. (2001) Densification and Structural Change of Mechanically Alloyed W-Cu Composites. Metallurgical and Materials Transactions A, 32, 2885-2893. http://dx.doi.org/10.1007/s11661-001-1039-0
[24]
Ryu, S.S., Kim, Y.D. and Moon, I.H. (2002) Dilatometric Analysis on the Sintering Behavior of Nanocrystalline W-Cu Prepared by Mechanical Alloying. Journal of Alloys and Compounds, 335, 233-240. http://dx.doi.org/10.1016/S0925-8388(01)01805-9
[25]
Igharo, M. and Wood, J. (1985) Compaction and Sintering Phenomena in Titanium—Nickel Shape Memory Alloys. Powder Metallurgy, 28, 131-139. http://dx.doi.org/10.1179/pom.1985.28.3.131
[26]
Koo, J.-M., Araki, H. and Jung, S.-B. (2008) Effect of Zn Addition on Mechanical Properties of Brass Hollow Spheres. Materials Science and Engineering: A, 483-484, 254-257. http://dx.doi.org/10.1016/j.msea.2006.01.183
Rajkumar, K. and Aravindan, S. (2009) Microwave Sintering of Copper-Graphite Composites. Journal of Materials Processing Technology, 209, 5601-5605. http://dx.doi.org/10.1016/j.jmatprotec.2009.05.017
[29]
Boonyongmaneerat, Y. (2009) Effects of Low-Content Activators on Low-Temperature Sintering of Tungsten. Journal of Materials Processing Technology, 209, 4084-4087. http://dx.doi.org/10.1016/j.jmatprotec.2008.09.026
