Long-term oxidation and phase transformations in aluminized CMSX-4 superalloys

Severe plastic deformation (SPD) processes, are successfully employed to produce ultra fine grain (UFG) and nanocrystalline (NC) microstructures in Ni50.7Ti49.3 shape memory alloy. The effect of grain size on phase transformations during annealing is investigated by differential scanning calorimetry (DSC) and transmission electron microscopy (TEM). The results of comparative studies of phase transformations in coarse-grained, UFG and NC alloys after SPD and subsequent long-term (up to 100 hours) annealing at 400С is presented. The functional properties and the innovation potential of UFG NiTi alloys is considered and discussed.

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Oxide scale formation and subsurface phase transformations during long-term steam exposure of the cobalt base alloy 25

Materials and Corrosion ◽

10.1002/maco.201206683 ◽

2012 ◽

Vol 63 (10) ◽

pp. 878-888 ◽

Cited By ~ 12

Author(s):

L. García Fresnillo ◽

A. Chyrkin ◽

T. Hüttel ◽

C. Böhme ◽

J. Barnikel ◽

...

Keyword(s):

Phase Transformations ◽

Oxide Scale ◽

Base Alloy ◽

Scale Formation ◽

Cobalt Base Alloy ◽

Cobalt Base

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Mechanism and Kinetics of Phase Transformations in Refractory Alloy 45Kh26N33S2B2 Under Long-Term High-Temperature Holds. Part 2

Metal Science and Heat Treatment ◽

10.1007/s11041-014-9717-x ◽

2014 ◽

Vol 56 (3-4) ◽

pp. 124-130 ◽

Cited By ~ 15

Author(s):

A. I. Rudskoy ◽

S. Yu. Kondrat’ev ◽

G. P. Anastasiadi ◽

A. S. Oryshchenko ◽

M. D. Fuks

Keyword(s):

High Temperature ◽

Phase Transformations ◽

Refractory Alloy ◽

Mechanism And Kinetics ◽

Kinetics Of

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Phase transformations after long-term heat treatment of solid solutions based on ZrO2 and HfO2

Refractories ◽

10.1007/bf01406888 ◽

1981 ◽

Vol 22 (9-10) ◽

pp. 489-495

Author(s):

A. G. Karaulov ◽

E. I. Zoz ◽

I. N. Rudyak ◽

T. E. Sudarkina

Keyword(s):

Heat Treatment ◽

Phase Transformations ◽

Solid Solutions

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Phase Transformations in Long-Term Aged Ni-Cr-Fe Alloys

Materials Science Forum ◽

10.4028/www.scientific.net/msf.126-128.375 ◽

1993 ◽

Vol 126-128 ◽

pp. 375-378

Author(s):

A. Marucco ◽

E. Signorelli

Keyword(s):

Phase Transformations ◽

Fe Alloys

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Structural Evolution of Al-Cr Alloy during Processing

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.138.145 ◽

2008 ◽

Vol 138 ◽

pp. 145-152 ◽

Cited By ~ 3

Author(s):

Dalibor Vojtěch ◽

Alena Michalcová ◽

Pavel Novák

Keyword(s):

Heat Treatment ◽

Solid Solution ◽

Phase Transformations ◽

Elevated Temperatures ◽

Supersaturated Solid Solution ◽

Structural Evolution ◽

Hot Extrusion ◽

Light Components ◽

Rapidly Solidified

Aluminium-chromium based alloys are promising candidates for manufacture of light components exposed to elevated temperatures. The work describes properties of Al-6.0wt.%Cr- 2.1wt.%Fe-0.5wt.%Ti alloy. The rapidly solidified powder was prepared by the pressure nitrogen melt atomization. The powder was then subject to heat treatment in order to investigate solid state phase transformations. Compaction of the powder was carried out by hot extrusion after preheating at 450 °C. Microstructure, phase composition and structural transformations on heat treatment were investigated in the as-atomized powder, as well as in the as-extruded alloy. It is found that metastable state of the rapidly solidified powder is characterized by presence of quasi-crystalline phases and supersaturated solid solution. Heating before and during the hot extrusion induces decomposition of the supersaturated solid solution and quasicrystalline to crystalline phase transformations. The hot extruded alloy has a refined recrystallized structure that remains very stable aven after long-term annealing at 400 °C. Mechanical properties of the extruded alloy are discussed in terms of strengthening mechanisms.

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