martensite

Definitions

  • WordNet 3.6
    • n martensite a solid solution of carbon in alpha-iron that is formed when steel is cooled so rapidly that the change from austenite to pearlite is suppressed; responsible for the hardness of quenched steel
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Century Dictionary and Cyclopedia
    • n martensite A very hard carbide of iron, approximately of the composition Fe24C, formed in the recalescenee of steel at 850° C. in cooling from a temperature of 1,000° C. or over. It remains unchanged if the metal is then suddenly cooled, as by plunging it into cold water, but on slow cooling is decomposed into iron and the carbide Fe3C. On the other hand, it appears that this latter compound, known as cementite, may split into martensite and carbon in the form of graphite.
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Usage

In literature:

Steel with 0.2 per cent carbon and 15 per cent nickel is entirely martensite.
"The Working of Steel" by Fred H. Colvin
If heated above 670deg, pearlite becomes homogeneous, and forms martensite.
"The Phase Rule and Its Applications" by Alexander Findlay
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In news:

There is a statement that says, "Given the opportunity, retained austenite will transform to martensite.".
Martensite development is critical to many heat-treatment processes.
Tempered Martensite Embrittlement Tempered martensite embrittlement is also known as TME.
The formation of martensite involves the structural rearrangement (by shear displacement) of the atoms from face-centered cubic (FCC) austenite into a body-centered tetragonal (BCT) martensitic structure.
Martensite development is critical to many heat-treatment processes.
Revision of A1010 / A1010M - 01(2009) Standard Specification for Higher-Strength Martensitic Stainless Steel Plate, Sheet, and Strip.
New developments in welding and thermal processing are enabling the cost-effective use of martensitic stainless steels in exciting new applications.
Temper Embrittlement Temper embrittlement may occur in certain types of martensitic steels that are generally tempered in the range of 800°F up to 1100°F.
Because of this, post-weld heat treatment is often very helpful in maintaining weld joint strength because it softens or tempers any martensite or bainite that formed in the HAZ.
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In science:

The summary of the models offered by the author revealing features of the physical mechanisms controlling processes of martensite crystal formation is resulted.
Physical nature of fcc-bcc martensitic transformation in iron based alloys
The rapid growth of a cooling martensite crystal is considered as a self-organized process controlled by the quasi-longitudinal lattice displacement waves (DW).
Physical nature of fcc-bcc martensitic transformation in iron based alloys
It is shown, that processes of the heterogeneous nucleation and wave growth have the genetic connection in case of spontaneous γ − α martensitic transformation.
Physical nature of fcc-bcc martensitic transformation in iron based alloys
The exposition of strain martensite formation is considered in the context of a cryston model.
Physical nature of fcc-bcc martensitic transformation in iron based alloys
As is known the spontaneous (cooling-induced), stress- induced and strain-induced α - martensites are distinguished.
Physical nature of fcc-bcc martensitic transformation in iron based alloys
Processes of martensite nucleation in all cases are heterogeneous.
Physical nature of fcc-bcc martensitic transformation in iron based alloys
Now it is obvious that only the wave approach would have the full potential for a comprehensive description of the dynamical aspects of the transformation process in the cases of spontaneous and stress-induced martensites.
Physical nature of fcc-bcc martensitic transformation in iron based alloys
With this approach, all macroscopic morphological characteristics of martensite attain a reasonable interpretation within the conceptual notion of nucleation at dislocations, where dislocations act as centers of forces disturbing the original lattice symmetry, their effect not being confined to the nuclear volume.
Physical nature of fcc-bcc martensitic transformation in iron based alloys
The strain-induced martensite formation is considered as a consequence of carry of a threshold plastic deformation by crystons.
Physical nature of fcc-bcc martensitic transformation in iron based alloys
As is shown in [12,13] the basic features of the strain-induced martensite is described if to consider the cryston as the carrier of the threshold deformation having character of simple shear.
Physical nature of fcc-bcc martensitic transformation in iron based alloys
For case of the cooling martensite this is the controlling wave process that is supported in the maser regime by nonequilibrium electrons due to the generation of energy in transforming phase.
Physical nature of fcc-bcc martensitic transformation in iron based alloys
For case of the strain martensite this is the process of the cryston propagations that are supported in basic by energy of exterior stresses.
Physical nature of fcc-bcc martensitic transformation in iron based alloys
Yablonskaya, A model of formation of macroshear bands and strain-induced martensite with (hhl) boundaries.
Physical nature of fcc-bcc martensitic transformation in iron based alloys
Neskoromnyi, Wave mechanism of growth and novel technique for initiation of the martensite nucleation.
Physical nature of fcc-bcc martensitic transformation in iron based alloys
Kashchenko, Dynamical Lattice State at the Initial Stage of Martensitic Transformation and Possibilities of its Physical Realization.
Physical nature of fcc-bcc martensitic transformation in iron based alloys
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