1. Overheating can result in tempered martensite ( OTM ) or untempered martensite ( UTM ) formations in the base metal.

2. The integrated intensities of the Austenite and martensite diffraction peaks are measured on our custom-designed diffractometers, providing four Austenite/martensite peak intensity ratios.

3. Austenite that does not transform to martensite upon quenching is called retained Austenite

4. Martensite stainless steel for an injection-moulding mould having improved corrosion resistance

5. Lines of constant volume fraction of martensite are nearly parallel in the stress-temperature plane.

6. This forms martensite, which is brittle and may lead to higher chances of micro-cracks.

7. Retained Austenite does become stable with time, and some will transform to martensite at room temperature

8. Retained Austenite, may be present, inter-mingled with martensite at room temper-ature (Fig

9. Retained Austenite does become stable with time and some will transform to martensite at room temperature

10. This behavior is attributed to the paramagnetic nature of austenite, while both martensite and ferrite are strongly ferromagnetic.

11. The dark-colored needles shown are tempered martensite crystals and the light-colored areas are retained Austenite crystals

12. This retained Austenite occurs when the steel is not quenched to a temperature low enough to form 100% martensite

13. The amount of retained Austenite is calculated using the direct comparison method and the ratio of two Austenite and two martensite diffraction peak intensities

14. The bainite-martensite mix is formed by air-cooling from solution treatment temperature and subsequent aging at secondary hardening temperatures to precipitate the toughening and strengthening dispersions.

15. The micro structure is acicular tempered martensite with 3-7% by volume of speheroidized and uniformly distributed cementite (undissolved carbides) in sizes below 3 micrometers.

16. As a result of the quenching, the face-centered cubic Austenite transforms to a highly strained body-centered tetragonal form called martensite that is supersaturated with carbon.

17. When B-III and B-II type bainite, which precipitated Acicularly so as to partition prior austenite grains, associated with lath martensite, a detrimental effect was found on the strength and

18. The quenched steel sheet according to an aspect of the present invention contains, in terms of wt%, C: 0.05-0.25%, Si: 0.5% or less (excluding 0), Mn: 0.1-2.0%, P: 0.05% or less, S: 0.03% or less, the remainder Fe, and other unavoidable impurities, wherein a refined structure of the steel sheet comprises 90 volume% or more of martensite with a first hardness and martensite with a second hardness.

19. Samuels [1] states that up to 5% of the Austenite present after quenching and low temperature tempering (<200 C) will transform to martensite soon after quenching or over a period of some months

20. Samuels[1] states that up to 5% of the Austenite present after quenching and low-temperature tempering (<200°C) will transform to martensite soon after quenching or over a period of some months

21. The substructure of retained Austenite differs from that of the original Austenite as it has a higher density of imperfections like dislocations, stacking faults, etc., which are created by local plastic deformation of the Austenite by martensite crystals.

22. The microstructure is characterised by a volume fraction > 20% of primary, acicular, M7C3 - type carbides of mean cross-sectional dimension of 75mu max. in a eutectic matrix of eutectic and secondary carbides and austenite and/or martensite.

23. The invention relates to a cast iron material which is characterized especially by a matrix comprising > 50 percent of acicular ferrite, < 20 percent of austenite, < 30 percent of martensite, < 50 percent of perlite, and < 15 % of carbide.

24. These weld metals have microstructures of acicular ferrite (16') interspersed in a hard constituent (11'), such as lath martensite, yield strengths of at least about 690 MPa (100ksi), and DBTTs lower than about -50°C (-58°F) as measured by a Charpy energy versus temperature curve.

25. Accordingly, the present invention is advantageous in that the cooling rate transmitted from the cooling water supply sections of the upper and lower molds can be delayed to prevent the trim cut from being quenched and thus being transformed into a martensite texture having high hardness, so that the wear on a trimming mold during a trimming process may be reduced, which in turn improves endurance and increases productivity.