Examination of Microstructures and Microanalysis of an Fe-9% Ni Alloy

Chong, S. H.; Sayles, A.; Keyse, R.; Atkinson, J. D.; Wilson, E. A.

doi:10.2320/matertrans1989.39.179

Cited by 12 publications

(17 citation statements)

References 25 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…22 is in agreement with previous work on Fe-7.4%Cr-1.8%Ni, 50) on a 0.23% C low alloy steel, 33) on an Fe-9%Ni alloy 3) and on a 0.18%C-1.1%Mn steel. 36,37) As stated previously the ferrite habit plane of (110) …”

Section: Crystallography and Morphology Of Massive Ferrite And Widmansupporting

confidence: 92%

“…This ferrite subsequently develops into Widmanstätten ferrite within the austenite grains with tent relief on prepolished surfaces. 3,4,[29][30][31][32][33][34][35][36][37] Similar structures were observed by Bodnar and Hansen 36,37) in a 0.18%C-1.1%Mn steel. As long ago as 1979, Entin and his co-workers 38) describe "Widmanstätten ferrite crystals, mainly observed inside the grains, with a network of polyhedral ferrite crystals in the boundary zone, the formation of which does not involve the development of micro-relief " in 0.03% C low alloy steels.…”

Section: Resultsmentioning

confidence: 56%

“…11(b) indicates the significant misorientation Ϯ7°about a common ͗111͘ b close-packed direction between massive ferrite grains. This grain boundary ferrite may be compared with the areas of massive ferrite seen by Chong et al 3) in furnace cooled Fe-9%Ni. Grain boundary ferrite forms heterogeneously at a high temperature on prior austenite grain boundaries.…”

Section: Resultsmentioning

confidence: 83%

“…However, different types of transformations may occur at different temperatures during cooling producing mixed morphologies. The work in this paper describes the morphology of massive ferrite [1][2][3] (a q ) and the crystallography of Widmanstätten ferrite 3,4) (a w ), bainitic ferrite [5][6][7][8] (a 0 B ), and lath (massive) martensite 9,10) (aЈ m ). The nomenclature in brackets is due to Araki et al 11) These microstructures were observed in Fe-15%Ni alloys under different austenitising conditions and cooling conditions.…”

Section: Introductionmentioning

confidence: 99%

“…3,14) Figure 1 for example shows the dilatation curve for a ISIJ International, Vol. 41 (2001) 15) 0.13% C high strength low alloy (HSLA) steel obtained during cooling at 1 K/s, 15) while Fig.…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

A Kinetic and Electronmicroscopic Study of Transformations in Continuously Cooled Fe-15%Ni Alloys.

2001

Self Cite

View full text Add to dashboard Cite

Koistinen and Marburger's equation relating volume fraction of athermal martensite to temperature has been applied to diffusional transformation dilatometry data obtained on continuous cooling Fe-15%Ni alloys. After austenitising for 1 h at 1 000°C and cooling at 50 K/min (0.83 K/s), grain boundary nucleated massive ferrite was observed which developed into Widmanstätten ferrite with a ferrite habit plane of {110} b for temperatures between 372°C and 352°C. On cooling at 44 K/s from 1 000°C bainitic ferrite was observed for temperatures below 360°C. There was some retained austenite in this bainitic structure giving a ferrite habit plane of {110} b parallel to the austenite plane {111} f . Cooling at the same rate, 44 K/s from 1 200°C gave lath martensite below the M s of 261°C with a ferrite habit plane of {112} b . Superlattice spots corresponding to the DO 3 or B2 structure were observed in electron diffraction patterns on cooling at 50 K/min (0.83 K/s) and 44 K/s from 1 000°C.

show abstract

Section: Crystallography and Morphology Of Massive Ferrite And Widmansupporting

confidence: 92%

Section: Resultsmentioning

confidence: 56%

Section: Resultsmentioning

confidence: 83%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

A Kinetic and Electronmicroscopic Study of Transformations in Continuously Cooled Fe-15%Ni Alloys.

2001

Self Cite

View full text Add to dashboard Cite

show abstract

Low Nickel Maraging Steel

Sha

2013

Steels

View full text Add to dashboard Cite

The kinetics of precipitate formation are analysed using the Johnson-Mehl-Avrami (JMA) theory. Nano-sized precipitates are formed homogeneously during the ageing process, which results in high hardness. As the ageing time is prolonged, precipitates grow and hardness increases. As-forged Fe-12.94Ni-1.61Al-1.01Mo-0.23Nb (wt%) steel has mixed ductile and brittle fracture and has good toughness. Relationships among heat treatment, microstructure and mechanical properties are discussed. Austenitisation with lower temperature and intercritical annealing are introduced in the treatment of the maraging steel. Intercritical annealing treatments do not increase hardness either before or after ageing. The impact toughness in aged condition is enhanced after austenitisation at 950 °C. Reverted austenite is suspected after austenitisation at 950 °C followed by ageing at 600 °C.

show abstract

Isothermal transformations in an Fe-9 pct Ni alloy

Wilson

Chong

2002

Metall Mater Trans A

Self Cite

View full text Add to dashboard Cite

Isothermal transformation from austenite in an Fe-9.14 pct Ni alloy has been studied by optical metallography and examination by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). In the temperature range 565 ЊC and 545 ЊC, massive ferrite (␣ q ) forms first at prior austenite grain boundaries, followed by Widmanstätten ferrite (␣ W ) growing from this grain boundary ferrite. Between 495 ЊC and 535 ЊC, Widmanstätten ferrite is thought to grow directly from the austenite grain boundaries. Both these transformations do not go to completion and reasons for this are discussed. These composition invariant transformations occur below T 0 in the two-phase field (␣ ϩ ␥). Previous work on the same alloy showed that transformation occurred to ␣ q and ␣ W on furnace cooling, while analytical TEM showed an increase of Ni at the massive ferrite grain boundaries, indicating local partitioning of Ni at the transformation interface. An Fe-3.47 pct Ni alloy transformed to equiaxed ferrite at 707 ЊC Ϯ 5 ЊC inside the single-phase field on air cooling. This is in agreement with data from other sources, although equiaxed ferrite in Fe-C alloys forms in the two-phase region. The application of theories of growth of two types of massive transformation by Hillert and his colleagues are discussed.

show abstract

Examination of Microstructures and Microanalysis of an Fe-9% Ni Alloy

Cited by 12 publications

References 25 publications

A Kinetic and Electronmicroscopic Study of Transformations in Continuously Cooled Fe-15%Ni Alloys.

A Kinetic and Electronmicroscopic Study of Transformations in Continuously Cooled Fe-15%Ni Alloys.

Low Nickel Maraging Steel

Isothermal transformations in an Fe-9 pct Ni alloy

Contact Info

Product

Resources

About