Founding Research Journal

Founding Research Journal

Effects of Cooling Rate after Homogenizing on the Microstructure and Tensile Properties of a New Generation Cobalt Base Superalloy

Document Type : Original Research Article

Authors
1 M.Sc. Student, Faculty of Material and Manufacturing Technologies, Malek Ashtar University of Technology, Tehran. Iran.
2 Associate Professor, Faculty of Material & Manufacturing Technologies, Malek Ashtar University of Technology, Tehran, Iran.
3 Associate Professor, Faculty of Materials Engineering, Hamedan University of Technology, Iran.
10.22034/frj.2024.426238.1189
Abstract
New cobalt-nickel base superalloys containing γ´ precipitates designed in order to achieve better high temperature properties than Ni base superalloys. In this article, the alloy with chemical composition of Co-28.7Ni-4.26Al-8.2Cr-17.4W-1.51Ti-2.85Ta-0.02C-0.01B (%W) casted and homogenized at 1300°C for 8hr. one sample quenched in air (1300-Air) and the other cold in furnace till 900°C and after that quenched in air (1300-900-Air). Microstructural investigation carried out using optical and electron scanning microscopy. Hardness and room and high temperatures of homogenized samples is also compared. The results showed that cast sample containing dendritic structure with primitive and secondary arms which eliminated after homogenizing. 1300-Air sample have finer grains and more scattered precipitates while 1300-900-Air sample have coarse grains and continuous precipitates at the grain boundaries. Room and high temperature ultimate tensile strength of 1300-900-Air are 775 and 232 MPa, respectively. These are 1027 and 282 MPa, respectively for 1300-Air sample which are more than ones for 1300-900-Air and related to finer grains and scattering the precipitates.
Keywords
Subjects

1.     Leyens C., Peters M., Titanium and Titanium Alloys - Fundamentals and Applications, Wiley‐VCH Verlag GmbH & Co. KGaA, 2003.
2.     Appel F., Paul J.D.H., Oehring M., Gamma Titanium Aluminide Alloys., Germany: Wiley-VCH Verlag & Co. KGaA, 2011.
3.     Sauthoff G., Intermetallics, ed. 1st. 1995, Weinheim: NY: Wiley-VCH.
4.     Bewlay B.P., et al., TiAl alloys in commercial aircraft engines. Materials at High Temperatures, 2016. 33: p. 549-559.
5.     Stollof N.S., Shikka V.K., Physical Metallurgy and Processing of Intermetallic Compounds. 1996, New York: Chapman & Hall.
6.     Rezaei H., Morakabati M., Momeni A., Evaluation of the effect of heat treatment on structural changes and mechanical properties of Ti-48Al-2Cr-2Nb intermetallic. Founding Research Journal, 2022, 6(2) 125-132.
7.     Jiang F., et al., A Correction to the stress–strain curve during multistage hot deformation of 7150 aluminum alloy using instantaneous friction factors, Journal of Materials Engineering and Performance, 2018, 27(6) 3083-3090.
8.     Goetz R.L., Semiatin S.L., The adiabatic correction factor for deformation heating during the uniaxial compression test, Journal of Materials Engineering and Performance, 2001, 10(6) 710-717.
9.     Li S., Li L., Influence of the deformation heating on the flow behavior of 6063 alloy during compression at medium strain rates, Journal of Materials Research, 2019, 34(2) 309-320.
10. Li Y.P., Matsumoto H., Chiba A., Correcting the stress-strain curve in the stroke-rate controlling forging process, Metallurgical and Materials Transactions A, 2009, 40, 1203-1209.
11. Brenk J., Hassan-Pour S., Spiess P., Friedrich B., Examination of an alternative method for the pyrometallurgical production of copper-chromium alloys, IOP Conf. Ser. Materials Science and Engineering, 2016, 143, 012016.
12. Franzén S.F., Karlsson J., Titanium Aluminide manufactured by electron beam melting, Master Thesis, in Department of Materials and Manufacturing Technology, Chalmers University of Technology: Gothenburg, Sweden, 2010.
13.  Monajati H., et al., Deformation characteristics of isothermally forged UDIMET 720 nickel-base superalloy, Metallurgical and Materials Transactions A, 2005, 36, 895-906.
14.  Ebrahimi R., Najafizadeh A., A new method for evaluation of friction in bulk metal forming, Journal of Materials Processing Technology, 2004, 152(2) 136-143.
15.  Tan X., Comparisons of friction models in bulk metal forming. Tribology International, 2002, 35, 385–393.
16.  Shahriari D., et al., Effects of lubricant and temperature on friction coefficient during hot forging of Nimonic 115 superalloy, Kovove Materialy, 2011, 49(5) 375-383.
17.  Rudkins N.T., et al., Friction modelling and experimental observations in hot ring compression tests. Journal of Materials Processing Technology, 1996, 60, 349-353.
18.  Obiko J., Friction correction of flow stress-strain curve in the upsetting process. IOP SciNotes, 2021, 2(1).
19.  Evans R.W., Scharning P.J., Axisymmetric compression test and hot working properties of alloys. Materials Science and Technology, 2001, 17, 995-1004.
20.  Dieter G.E., Kuhn H.A., Semiatin S.L., Handbook of workability and process design, USA: ASM International, 2003.
21.  Doubenskaia M., et al., Study of selective laser melting of intermetallic TiAl powder using integral analysis, International Journal of Machine Tools and Manufacture, 2018, 129, 1-14.
22.  Xiao G., Yang Q.W., Li L.X., Modeling constitutive relationship of 6013 aluminum alloy during hot plane strain compression based on Kriging method. Transactions of Nonferrous Metals Society of China, 2016, 26(4) 1096-1104.
23.  Chen X., et al., Dynamic recrystallization behavior of the Ti–48Al–2Cr–2Nb alloy during isothermal hot deformation, Progress in Natural Science: Materials International, 2019, 29, 587-594.
24.  Ma Y., et al., Correction of flow stress for hot compression of IN718 alloy, in International Conference on Manufacturing Science and Engineering, Atlantis Press, 2015, 1431-1436.
Volume 8, Issue 2 - Serial Number 25
Autumn and Winter
Autumn 2024
Pages 81-88

  • Receive Date 20 November 2023
  • Revise Date 09 July 2024
  • Accept Date 11 July 2024