TPT January 2012

A rticle

Structure of initial plain section (microsections)

Item

Name

Unit

Value

1 Number of objects (grains)

pcs μm μm μm

695

2 Maximum grain size

37.67 10.17

3 Average grain diameter in a volume

4 Mean square deviation 5 Coefficient of variation

4.83 0.48

6 Number of grains in 1 mm 2 of microsections

pcs

12784

0.05436324

7 Total grain area

mm 2

8 Number of grains in 1 mm 3 of volume

pcs

1445440

9 Grain number according to standard GOST 5639 10 Grain number according to standard ASTM E 112

11

10.5

Coefficient of variation of the structure

In a volume

In a plane

In a line

0.48

0.54

0.57

Structure after computer processing

Figure 1 : Characteristics of a comparatively homogeneous structure

Structure of initial plain section (microsections)

Item

Name

Unit

Value 6385

1 Number of objects (grains)

pcs

2 Maximum grain size

μm 148.90

3 Average grain diameter in a volume

μm μm

29.62 20.86 0.70 1848

4 Mean square deviation 5 Coefficient of variation

6 Number of grains in 1 mm 2 of microsections

pcs

0.20832358

7 Total grain area

mm 2

8 Number of grains in 1 mm 3 of volume

pcs

79442

9 Grain number according to standard GOST 5639 10 Grain number according to standard ASTM E 112

8

7.5

Coefficient of variation of the structure

In a volume

In a plane

In a line

0.7

0.71

0.72

Structure after computer processing

Figure 2 : Characteristics of an anisomery structure

2. Complex alloyed molybdenum steels and alloys possess a maximum grain anisotropy. Index of anisotropy for this steel is within 1.8-2.0 at a rapid heating 3. Increase in duration of isothermal heating results in an increase in the grain anisotropy proportionally to the heating temperature References: 1. I.L. Mayevsky. Plastic working of heat-resistant alloy. Мoscow, Mashinostroyenie Publishers, 1964. p123 2. Ye.Ya. Lezinskaya. Investigation of effect of heating conditions on recrystallization processes during heat treatment of cold-worked stainless and heat-resistant steels. Cand. Sc Theses, VNITI. Dnepropetrovsk. 1972. p155 3. Ye.Ya. Lezinskaya. Меthods of control of structure anisotropy during heat treatment of tubes made of high-alloy steels and alloys // Proizvodstvo Trub I Ballonov (Manufacture of tubes and cylinders). Dnepropetrovsk: ДТИ, 1999. pp. 109-116 4. V.V.Perchanik, Ye.Ya.Lezinskaya, D.Yu.Klyuev. Application of the stereology reconstruction methods in assessment of the spatial grain structure of metals and alloys. Tube & Pipe Technology Magazine. November 2010 – p114 5. V.V.Perchanik, Ye.Ya.Lezinskaya, Ye.V. Gulkin, D.Yu.Klyuev. The new method of reconstruction of grain structures by a planar section. Report 2. // Теоriya I Praktika Metallurgii. - No.6. Dnepropetrovsk – 2007. – pp. 50-56

6. D.Yu.Klyuev, Ye.Ya.Lezinskaya, V.V.Perchanik. Assessment of correctness of utilisation of a spherical grain shape in reconstruction of spatial structure of metals and alloys // Теоriya I Praktika Metallurgii. - No. 3-4. Dnepropetrovsk – 2010. – pp. 70-74 7. Inventor’s Certificate No.1577 Ukraine. Software STRUCTURE 2001/ V.V.Perchanik, D.Yu.Klyuev, Ye.Ya.Lezinskaya, Ye.V. Gulkin - No. 15901.:Application date 27.12.2006; Published in Bulleten DDIV “Authors Right and other rights” No.9, 2006 8. Т.P. Danilenko. Оptimization of thermal treatment regimes for especially thin-walled tubes of austenitic steels based on the development of a new method for determination of spatial structure parameters. Cand.Sc. Theses. Dnepropetrovsk. 1988. p226 9. М.N. Bodiako, S.А. Astapchik, G.B. Yaroshevich. Тhermikinetics of recrystallization // Nayka I Tekhnika. Мinsk. 1968. p249 10. V.I. Ivanov, К.А.Оsipov. Return and recrystallization in alloys during rapid heating. Наuka Publishers. Моscow.1964. p185

For more information please contact: Nataliya Koryaka Representative of International Tube Association in CIS countries Tel: +380 56 744 25 16 Email: koryakan@gmail.com

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