Sintering Effects on the Microstructure and Mechanical Properties of CoCrMo Alloy

Abstract:

Cobalt chromium molybdenum (CoCrMo) alloy is widely used in artificial hip and knee joints because of their excellence corrosion and wear resistance, as well as good mechanical properties and biocompatibility. This study investigates the effect of sintering temperature on the microstructure and mechanical properties of CoCrMo using powder metallurgy technique. CoCrMo powder was mixed with zinc stearate and then put into the shaker mixer at 65 rpm for 3 hours. The powder was then compacted at a pressure of 18T using an automated hydraulic press and sintered at a temperature in the range of 1200 – 1400 °C under 95 Vol% N₂/ 5 Vol% H₂ atmosphere. The microstructure, physical and mechanical properties of the samples are analyzed using scanning electron microscopy (SEM), Vickers’s microhardness tester and transverse rupture strength (TRS). The study reveals that the density, hardness and strength of CoCrMo samples increase as sintering temperature increases.

• Periodical: Advanced Materials Research (Volume 1133)
• Pages: 259-263
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.1133.259
• Online since: January 2016
• Authors: Mohd Hasnan Abdull Hamid, Fazira Suriani Mohamed Fadzil*, Mohd Asri Selamat, M.A. Ahmad
• Keywords: CoCrMo, Density, Hardness, Mechanical Properties, Microstructure, Sintering Temperature, Transverse Rupture Strength (TRS)

References

[1] M.F. Fazira, M. Mohammad, N. Roslaini, M.H. Saleh, M.A. Ahmad. Low strain rate upset forging of preformed CoCrMo powder alloy for load bearing application: A review. Procedia Engineering. (2013) 405-410.

DOI: 10.1016/j.proeng.2013.12.199

[2] W.C. Rodrigues, L.R. Broilo, L. Schaeffer, G. Knornschild, F. D Mallui Espinoza. Powder Metallurgical processing of Co-28%Cr-6%-Mo for dental implants: Physical, mechanical, and electrochemical properties. Powder Technology, (2010).

DOI: 10.1016/j.powtec.2010.09.024

[3] M. G Kamardan, N. Hidayah A. Zaidi, M. Noh Dalimin, A. Mujahid A. Zaidi, S. Bahrin jamaludin, M. Mahadi A. Jamil. The Sintering Temperature Effect on the Shrinkage Behaviour of Cobalt Chromium Alloy. American journal of Applied Sciences. (2010).

[4] Goutam. Dutta, Dr. Dipankar Bose. Effect of Sintering Temperature on Density, Porosity, and Hardness of a Powder Metallurgy Component. International Journal of Emerging Technology and Advanced Engineering. (2012) 121-123.

[5] M. Dourandish, D. Godlinski, A. Simchi, V. Firouzdor. Sintering of biocompatible P/M Co-Cr-Mo alloy (F-75) for fabrication of porosity-graded composite structures. Materials Science & Engineering. (2008) 338-346.

DOI: 10.1016/j.msea.2007.03.043

[6] 3T RPD. Metal AM Materials. Retrieved from 3T RPD Ltd Web Site: http: /www. 3trpd. co. uk/wp-content/uploads/2015/05/Cobalt-Chrome-Alloy-Co28Cr6Mo. pdf.