A study of the effects of phosphorus content, cold rolling and heat treatment on the kinetics of ordering in Ni2Cr alloys

The work presents the results on the structure of CuNi2Si1 copper alloy. The alloy was treated in two variants: supersaturation - aging (variant I) and supersaturation - cold rolling - aging (Variant II).The structure of the CuNi2Si1 alloyed copper were analyzed by high resolution transmission electron microscopy (HRTEM). The TEM investigation showed in the Cu matrix after applying cold rolling after solution heat treatment, during aging at 600°C, causes the Ni2Si phase occurrence immediately after the begin of aging. Cold rolling (50% reduction) of the CuNi2Si1 alloy after supersaturation changes the mechanism and kinetics of precipitation and provides possibilities for production of broader sets of functional properties.

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Engineering mechanical properties by controlling the microstructure of an Fe–Ni–Mn martensitic steel through pre-cold rolling and subsequent heat treatment

Materials Science and Engineering A ◽

10.1016/j.msea.2021.140760 ◽

2021 ◽

Vol 804 ◽

pp. 140760

Author(s):

Hamidreza Koohdar ◽

Pouya Hakimipour ◽

Hamid Reza Jafarian ◽

Terence G. Langdon ◽

Mahmoud Nili-Ahmadabadi

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Cold Rolling ◽

Martensitic Steel ◽

Subsequent Heat Treatment

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Magnetic Properties, Nanostructure, and Ordering Kinetics of Nb Additive FePtCu Films

Materials Science Forum ◽

10.4028/www.scientific.net/msf.638-642.1743 ◽

2010 ◽

Vol 638-642 ◽

pp. 1743-1748

Author(s):

G.J. Chen ◽

Y.H. Shih ◽

Jason S.C. Jang ◽

S.R. Jian ◽

P.H. Tsai ◽

...

Keyword(s):

Heat Treatment ◽

Activation Energy ◽

Magnetic Properties ◽

Heating Rates ◽

Fept Alloy ◽

Ordering Kinetics ◽

Nb Content ◽

Kinetics Of ◽

Nb Addition ◽

Microstructure And Magnetic Properties

In this study,the (FePt)94-xCu6Nbx (x=0, 2.87, 4.52, 5.67) alloy films were prepared by co-sputtering. The effects of Nb addition content and heat treatment on the microstructure and magnetic properties of the polycrystalline FePtCu films are reported. Our previous experiments showed that the ordering temperature of the (FePt)94Cu6 films reduced to 320 °C, which is much lower than that of the FePt alloy. However, the grain growth after heat treatment limited the practical application in recording media. By adding the Nb content in the (FePt)94Cu6 film, the grain sizes of the films can be adjusted from 50 to 18nm, even for the films annealed at temperature as high as 600°C. DSC traces of as-deposited disorder films at different heating rates, to evaluate the crystallization of the order phase, revealed that the addition of Nb enhanced the activation energy of ordering from 87 kJ/mol to 288 kJ/mol for the (FePt)94-xCu6Nbx (x=0 and 2.87, respectively) films. The reduction of the grain size and the corresponding increase in the activation energy of the Fe-Pt-Cu-Nb films might result from the precipitation of the Nb atoms around the ordering FePt phase. The (FePt)94-xCu6Nbx (x=2.87) film showed a coercive force of 13.4 kOe and the magnetization of 687 emu/cc.

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