Effect of Particle Size on the Compressibility and Sintering of Titanium Powders

Document Type : Research Paper

Authors

Science and Research Branch, Islamic Azad University of Tehran, Tehran, Iran

Abstract

In this research, the effects of the powder particle size on the compaction and sintering of Hydride‌–Dehydride titanium powders are investigated. Commercially pure titanium powders with three different size ranges were utilized. Compaction was accomplished under applied pressures of 200 to 650 MPa. Sintering was carried out at 1100 to 1400 ºC temperatures. The compressibility behavior of the differently-sized powders was studied by measuring the density of the green compacts. The microstructure of produced compacts was studied using scanning electron microscopy. Results showed that the small powders have the least compressibility. The compressibility data was analyzed and studied by common compaction equations. The modified Heckel equation showed the best correspondence. In addition, measuring the density of sintered compacts showed that the small powders had the highest sinterability. The highest amount of sintered density (98% theoretical) was attained for the small powder compacted under 650 MPa and sintered at 1400 ºC. However, the sintering temperature of 1200 ºC was recognized as the most appropriate temperature for the middle and large-sized titanium powders. The results of hardness tests showed that the appropriate mechanical properties could be attained for commercially pure titanium powder compacts by vacuum sintering accomplished at the optimum sintering circumstances.

Keywords


[1] X. Guo, L. Ma, A. Inoue, Improved hydrogen storage capacity of Ti60Zr15Ni15Cu10 amorphous alloy, Materials Transactions, 42 (2001) 2133-2135.
[2] H. Kim, K. Maruyama, Parallel twinning during creep deformation in soft orientation PST crystal of TiAl alloy, Acta Materialia, 49 (2001) 2635-2643.
[3] J.I. Qazi, J. Rahim, O.N. Senkov, F.H. Froes, Phase transformations in the Ti-6Al-4V-H system, JOM., 54 (2002) 68-71.
[4] O.N. Senkov, F.H. Froes, Thermohydrogen processing of titanium alloys, International Journal of Hydrogen Energy, 24 (1999) 565-576.
[5] G.S. Upadhyaya, Powder metallurgy technology, Cambridge Int Science Publishing, Cambridge, 1997.
[6] A. Hadadzadeh, M.A. Whitney, M.A. Wells, S.F. Corbin, Corbin, Analysis of compressibility behavior and development of a plastic yield model for uniaxial die compaction of sponge titanium powder, Journal of Materials Processing Technology, 243 (2017) 92-99.
[7] R. Ge, A new powder compaction equation, International Journal of Powder Metallurgy, 27 (1991) 211-216.
[8] R. Panelli, F.A. Filho, A study of a new phenomenological compacting equation, Powder Technology, 114 (2001) 255-261.
[9] R. Heckel, Density-pressure relationships in powder compaction, Transactions Metallurgy Society AIME, 221 (1961) 671-675.
[10] M. Moazami-Goudarzi, F. Akhlaghi, Effect of nanosized SiC particles addition to CP Al and Al–Mg powders on their compaction behavior, Powder Technology, 245 (2013) 126-133.
[11] R. Machaka, H.K. Chikwanda, Analysis of the cold compaction behavior of titanium powders: a comprehensive inter-model comparison study of compaction equations, Metallurgical and Materials Transactions A, 46 (2015) 4286-42-97.
[12] A. Simchi, Effects of lubrication procedure on the consolidation, sintering and microstructural features of powder compacts, Materials & Design, 24 (2003) 585-594.
[13] A. Simchi, G. Veltl, Investigation of warm compaction and sintering behaviour of aluminium alloys, Powder Metallurgy, 46 (2003) 159-164.
[14] R.M. German, Powder metallurgy science, Metal Powder Industries Federation, 1994.
[15] F. Tang, I.E. Anderson, S.B. Biner, Biner, Solid state sintering and consolidation of Al powders and Al matrix composites, Journal of Light Metals, 2 (2002) 201-214.
[16] L. Bolzoni, P.G. Esteban, E.M. Ruiz-Navas. E. Gordo, Influence of powder characteristics on sintering behaviour and properties of PM Ti alloys produced from prealloyed powder and master alloy, Powder Metallurgy, 54 (2011) 543-550.
[17] M. Qian, F.H. Froes, Titanium Powder Metallurgy: Science, Technology and Applications Butterworth-Heinemann, Massachusetts, (2015).
[18] ASM Handbook, Powder metal technologies and applications, Materials Park, OH: ASM International, Vol. 7 (1998).
[19] P.J. Denny, Compaction equations: a comparison of the Heckel and Kawakita equations, Powder Technology, 127 (2002) 162-172.
[20] N.D. Gentis, G. Betz, Compressibility of binary powder formulations: investigation and evaluation with compaction equations, Journal of Pharmaceutical Sciences, 101 (2012) 777-793.
[21] R. Boyer, G. Welsch, E.W. Collings, Materials Properties Handbook: Titanium Alloys, ASM International, (1993).
[22] F. Thummler, An Introduction to Powder Metallurgy, Institute of Materials Series on Powder Metallurgy, CRC Press, (1994).
[23] J. Shon, J. Park, K. Cho, J. Hong, N. Park, M. Oh, Effects of various sintering methods on microstructure and mechanical properties of CP-Ti powder consolidations, Transactions of Nonferrous Metals Society of China, 24 (2014) 59-67.