Kinetical analysis of the heat treatment procedure in SmCo5 and other rare-earth transition-metal sintered magnets

In the case of the modeling of sintering and heat treatments, the diffusion coefficients are an essential input. However, experimental data in the literature about diffusion coefficients for rare-earth transition metal intermetallics is scarce. In this study, the available data concerning diffusion coefficients relevant for rare-earth transition metal magnets are reviewed and commented. Some empirical rules are discussed, for example the activation energy is affected by the size of the diffusing impurity atom. Diffusion coefficients for Dy, Nd and Fe into Nd2Fe14B are given according an Arrhenius equation D=D0exp (-Q/RT). For Dy diffusion into Nd2Fe14B, Q 315 kJ/mol and D08 . 10-4m2/s.

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Magnetocaloric and other Properties of Cold Rolled Gd Ribbons

Materials Science Forum ◽

10.4028/www.scientific.net/msf.738-739.441 ◽

2013 ◽

Vol 738-739 ◽

pp. 441-445

Author(s):

Sergey Taskaev ◽

Vasiliy D. Buchelnikov ◽

Anatoliy Pellenen ◽

Dmitriy Bataev ◽

Konstantin Skokov ◽

...

Keyword(s):

Heat Treatment ◽

Heat Capacity ◽

Magnetocaloric Effect ◽

Treatment Procedure ◽

Magnetic Cooling ◽

Cooling Devices ◽

Cold Rolled ◽

Heat Treatment Procedure

In this work we investigate magnetocaloric effect and heat capacity of Gd cold rolled ribbons. Such materials are easy to produce, they are flexible and convenient for using in magnetic cooling devices. It is shown that the magnetocaloric effect is strongly dependent on thickness of the ribbons. Severely rolled ribbons demonstrate rather a small magnetocaloric effect. However, a special heat treatment procedure makes it possible to enhance the effect up to the value observed in polycrystalline Gd.

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A Heat treatment procedure to produce fine-grained lamellar microstructures in a P/M titanium aluminide alloy.

10.22215/etd/1997-03709 ◽

1997 ◽

Author(s):

Peter Au

Keyword(s):

Heat Treatment ◽

Titanium Aluminide ◽

Treatment Procedure ◽

Fine Grained ◽

Titanium Aluminide Alloy ◽

Heat Treatment Procedure

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Heat Treatment Procedure Qualification for Steel Castings

10.2172/807809 ◽

2003 ◽

Author(s):

Professor Robert C. Voigt

Keyword(s):

Heat Treatment ◽

Treatment Procedure ◽

Steel Castings ◽

Heat Treatment Procedure

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Warm Forming and Paint Bake Response of AW-7xxx Sheet in Various Tempers

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.651-653.47 ◽

2015 ◽

Vol 651-653 ◽

pp. 47-52 ◽

Cited By ~ 2

Author(s):

Manoj Kumar ◽

Nigel Ross

Keyword(s):

Heat Treatment ◽

Dynamic Recovery ◽

Warm Forming ◽

Treatment Procedure ◽

Processing Chain ◽

Peak Aged ◽

One Step ◽

The Stability ◽

Various Tempers ◽

Heat Treatment Procedure

In this paper, we have investigated AW-7921 in various tempers - specifically under aged T4P1-and T4P2-tempers, naturally aged T4 and peak-aged T6-tempers - for their warm formability at 230°C and paint baking response through one step and five step paint baking treatments. It was found that warm formability depends on dynamic recovery and dissolution of precipitates. However, the response to paint baking was dependent on the stability of the precipitates against coarsening. Of the tempers investigated the T4-temper exhibited the best combination of formability and paint baking response. This study also indicated that we can achieve much better performance in the warm forming processing chain by optimization of the temper and paint baking heat treatment procedure.

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Titanium-Suicide Contacts on GaAs

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100118722 ◽

1985 ◽

Vol 43 ◽

pp. 370-371

Author(s):

Z. Liliental ◽

A. Wakita ◽

C. Kocot ◽

J. Washburn ◽

R. Gronsky

Keyword(s):

Heat Treatment ◽

Electron Microscope ◽

Cross Section ◽

Schottky Contacts ◽

Electrical Parameters ◽

Treatment Procedure ◽

X Ray ◽

Electron Energy Loss ◽

Electron Energy Loss Spectra ◽

Heat Treatment Procedure

Successful use of titanium silicides as contacts on Si suggested the possibility of their application as Schottky contacts on GaAs. One composition of Ti:Si with the ratio 1:3 annealed for 5 sec at 875°C was found to result in good Schottky contacts. The barrier height and ideality factor were 0.8 eV and 1.15, respectively. The same heat treatment procedure for the composition of Ti:Si 1:2 did not give satisfactory electrical parameters.Cross section samples were prepared from these contacts for both compositions and were examined in a JEOL 200 CX electron microscope. Energy dispersive X-ray (EDX) and electron energy loss spectra (EELS) were taken using a Phillips 400 FEG electron microscope at 100 KV accelerating voltage.As-deposited structures with Ti:Si ratios 1:2 and 1:3 consisted of four alternate Ti and Si layers with different thicknesses. The interface of the first Ti layer with GaAs was very flat and abrupt for both compositions.

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