Journal of Thermal Analysis and Calorimetry

, Volume 102, Issue 3, pp 857–862 | Cite as

On the non-isothermal precipitation of copper-rich phase in 17-4 PH stainless steel using dilatometric techniques

  • B. Rivolta
  • R. Gerosa


The kinetics of the precipitation of copper-rich phase in 17-4 PH stainless steel was studied in this paper by non-isothermal dilatometric experiments. The dilatometric curve was analyzed and the conversion degree of the precipitates was associated with the area under the derivative curve of the thermal expansion as a function of temperature. The apparent activation energy associated with the formation of the precipitates was calculated and the obtained results were compared with the data calculated from the isothermal dilatometric tests presented in a previous paper. The data well agree, so confirming that non-isothermal dilatometry can be considered a powerful method to study the precipitation kinetics of PH stainless steels. Finally, the conversion degree for any isothermal treatment was calculated starting from the parameters obtained by non-isothermal dilatometric tests and compared with the conversion degree calculated from the hardness values during heat treatments.


17-4 steel Precipitation Dilatometry Heat treatments 


  1. 1.
    Martin JW. Precipitation hardening. 2nd ed. Oxford: Butterworth-Heinemann; 1998.Google Scholar
  2. 2.
    Metallic Materials Properties Development and Standardization (MMPDS), Office of Aviation Research Washington, D.C. 20591, 2003.Google Scholar
  3. 3.
    Hsiao CN, Chiou CS, Yang JR. Ageing reactions in a 17–4 PH stainless steel. Mater Chem Phys. 2002;74(2):134–42.CrossRefGoogle Scholar
  4. 4.
    El Hilali F, Habashi M, Mohsine A. Comportement mecanique de l’acier inoxydable martensitique 17–4 PH en corrosion sous contrainte et a la fragilisation par l’hydrogene environnemental. Ann Chim Sci Mater. 1999;24(3):169–94.CrossRefGoogle Scholar
  5. 5.
    Faccoli M, Ghidini A, Roberti R, A study of the strengthening mechanism in the novel precipitation hardening keylos®2001 steel. In: Proceedings of the 7th international tooling conference, II, Torino, 2–5 May 2006. p. 153–61.Google Scholar
  6. 6.
    Garcìa de Andrés C, Caballero FG, Capdevila C, Álvarez LF. Application of dilatometric analysis to the study of solid-solid phase transformations in steels. Mater Charact. 2002;48(1):101–11.CrossRefGoogle Scholar
  7. 7.
    Frigeni A, Gerosa R, Rivolta B, Derudi U, Il dilatometro per seguire l’invecchiamento delle leghe leggere, 18° Convegno Nazionale Trattamenti Termici, AIM—Associazione Italiana di Metallurgia, Rimini, 12-14 Giugno, 2001. p. 437–46.Google Scholar
  8. 8.
    Gerosa R, Rivolta B, Sala A. Optimization of the heat treatment of a 17–4 PH stainless steel by dilatometric technique. J ASTM Int. 2008;5:8.Google Scholar
  9. 9.
    Luiggi N, Betancourt M. On the non-isothermal precipitation of the β′ and β phases in Al-12.6 mass% Mg alloys using dilatometri techniques. J Therm Anal Calorim. 2003;74:883–94.CrossRefGoogle Scholar
  10. 10.
    Rivolta B, Pinasco MR. Study of the age-hardening in a Au–Cu–Ag dental alloy with Pt and Pd additions with dilatometry, hardness measurements and microstructural analysis. Int J Microstruct Mater Prop. 2009;4(5):487–506.CrossRefGoogle Scholar
  11. 11.
    Rivolta B, Gerosa R, Pinasco MR, Pellati G. Dilatometric analysis for investigating age hardening in a commercial precious metal dental alloy. J ASTM Int. 2009;6:2.Google Scholar
  12. 12.
    Luiggi N, Betancourt AE. Multiphase precipitation of carbides in Fe–C systems: part I. Model based upon simple kinetic reactions. Metall Mater Trans B. 1994;25B(4):917–25.CrossRefGoogle Scholar
  13. 13.
    Premkumar T, Govindarajan S, Coles AE, Wight CA. Thermal decomposition kinetics of hydrazinium cerium 2,3-pyrazinedicarboxylate hydrate: a new precursor for CeO2. J Phys Chem B. 2005;109:6126–9.CrossRefGoogle Scholar
  14. 14.
    Vyazovkin S, Sbirrazzuoli N. Isoconversional kinetic analysis of thermally stimulated processes in polymers. Macromol Rap Commun. 2006;27:1515–32.CrossRefGoogle Scholar
  15. 15.
    Jablonski AE, Lang AJ, Vyazovkin S. Isoconversional kinetics of degradation of polyvinylpyrrolidone used as a matrix for ammonium nitrate stabilization. Thermochim Acta. 2008;474(1–2):78–80.CrossRefGoogle Scholar
  16. 16.
    Vyazovkin S, Rives V, Schick C. Making impact in thermal sciences: overview of highly cited papers published in Thermochimica Acta. Thermochim Acta. 2010;500(1–2):1–5.CrossRefGoogle Scholar

Copyright information

© Akadémiai Kiadó, Budapest, Hungary 2010

Authors and Affiliations

  1. 1.Dipartimento di MeccanicaPolitecnico di MilanoMilanItaly

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