Acta Metallurgica Sinica (English Letters) ›› 1991, Vol. 4 ›› Issue (1): 33-36.

• Research paper • Previous Articles     Next Articles

PRECIPITATION HARDENING OF ELINVAR ALLOY

LIU Zhiguo CHEN Yong CAO Yanni Nanjing University,Nanjing,ChinaZHU Zhengsheng Shaanxi Iron and Steel Institute,Xi'an,China Professor,Dept.of Physics,Nanjing,University,Nanjing 210008,China   

  • Received:1991-02-25 Revised:1991-02-25 Online:1991-02-25 Published:2009-10-10

Abstract: The microstructural evolution and precipitation hardening of an Elinvar alloy doped with Ti and Al during isothermal aging at 700℃ have been investigated by atom probe field ion microscopy and microhardness measurements.The γ′ precipiates are spherical and coherent with the matrix.The chemical composition of the precipitates are(Ni_(0.53)Fe_(0.47)_3 (Ti_(0.(?))Al_(0.4)). During aging,a Lifshitz-Wagner type dissolution and coarsening reaction of the precipitates has been observed,The hardness of the material varies with the aging time and reaches maxi- mum when the average diameter of the precipitates was about 11 nm.

Key words: Elinvar alloy, atom probe field ion microscope, γ-phase, precipitation hardening, atom probe selected area analysis