GOST 19265-73

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  ГОСТ 19265-73

GOST 19265−73 Bars and strips of high speed steel. Technical specifications (with Changes 1−6 N)

GOST 19265−73
Group В32

INTERSTATE STANDARD

BARS AND STRIPS OF HIGH SPEED STEEL

Specifications

Bars and strips of high-speed steel. Specifications

ISS 77.140.60
OKP 09 6200

Date of introduction 1975−01−01

Promulgated by decree of the State Committee of standards of Ministerial Council of the USSR dated 10 December 1973, N 2678

Limitation of actions taken by Protocol No. 2−92 of the Interstate Council for standardization, Metrology and certification (ICS 2−93)

INSTEAD 9373−60 GOST and GOST 5952−63

EDITION Changes N 1, 2, 3, 4, 5, 6, approved in June 1977, August 1981, October 1983, July 1985, November 1987, June 1990 (IUS 8−77, 10−81, 2−84, 10−85, 2−88, 10−90).


This standard applies to hot rolled, forged, calibrated bars and strips, rods with special surface finish (further — products), as part of the rules of the chemical composition — in sheet, strip, forgings, stamping and other types of steel products of high speed steel.

The standard fully complies ST SEV 3896−82.

(Changed edition, Rev. N 3).

1. BRAND

1.1. Brand and chemical composition on plavonia analysis shall be as specified in table.1.

Table 1

Steel grade	Mass fraction of element, %
	the corner — kind of	Mar Ganz	cream tion	chrome	WOL — FRAM	Vana — dia	co — Balta	molyb — den	no — Kehl	copper	sulfur	Foz fora	nitrogen	nio — Biya
									no more
R18	0,73- 0,83	0,20- 0,50	0,20- 0,50	3,80- 4,40	17,00- 18,50	1,00- 1,40	Not more than 0,50	No more than 1,00	0,6	0,25	0,030	0,030	-	-
R6M5	0,82- 0,90	0,20- 0,50	0,20- 0,50	3,80- 4,40	5,50- 6,50	1,70- 2,10	Not more than 0,50	4,80−5,30	0,6	0,25	0,025	0,030	-	-
11R3AM3F2	Of 1.02- 1,12	0,20- 0,50	0,20- 0,50	3,80- 4,40	2,50- 3,30	2,30- 2,70	Not more than 0,50	2,50−3,00	0,6	0,25	0,030	0,030	Of 0.05 — 0.10	0,05 — 0,20
R6M5F3	0,95- 1,05	0,20- 0,50	0,20- 0,50	3,80- 4,30	5,70- Of 6.70	2,30- 2,70	Not more than 0,50	4,80−5,30	0,6	0,25	0,025	0,030	-	-
R12F3	0,95- 1,05	0,20- 0,50	0,20- 0,50	3,80- 4,30	12,00- 13,00	2,50- Of 3.00	Not more than 0,50	No more than 1,00	0,6	0,25	0,030	0,030	-	-
R18K5F2	0,85- 0,95	0,20- 0,50	0,20- 0,50	3,80- 4,40	17,00- 18,50	1,80- 2,20	4,70- 5,20	No more than 1,00	0,6	0,25	0,030	0,030	-	-
R9K5	0,90- Of 1.00	0,20- 0,50	0,20- 0,50	3,80- 4,40	9,00- 10,00	2,30- 2,70	5,00- 6,00	No more than 1,00	0,6	0,25	0,030	0,030	-	-
R6M5K5	0,86- 0,94	0,20- 0,50	0,20- 0,50	3,80- 4,30	5,70- Of 6.70	1,70- 2,10	4,70- 5,20	4,80−5,30	0,6	0,25	0,030	0,030	-	-
R9M4K8	1,00- 1,10	0,20- 0,50	0,20- 0,50	3,00- 3,60	8,50- 9,50	2,30- 2,70	7,50- 8,50	3,80−4,30	0,6	0,25	0,030	0,030	-	-
R2AM9K5	1,00- 1,10	0,20- 0,50	0,20- 0,50	3,80- 4,40	1,50- Of 2.00	1,70- 2,10	4,70- 5,20	8,00−9,00	0,6	0,25	0,030	0,030	Of 0.05 — 0.10	0,10 — 0,30

Notes:

1. Steel stamps letters and numbers mean: P — high speed; the figure following the letter, is the average mass fraction of tungsten, M — molybdenum, f — vanadium, cobalt, And nitrogen; the numbers following the letters indicate respectively the mass percent of molybdenum, vanadium, cobalt; W — electroslag remelting.

In the designation of steel grades do not indicate mass fraction:

chrome — with any mass fraction,

molybdenum up to 1%, inclusive,

vanadium in steel grades R18, R6M5, R9K5, R6M5K5, and R9M4K8 R2AM9K5,

nitrogen in steel grades 11R3AM3F2 and R2AM9K5.

2. At customer’s request, produce steel of grade R6M5 and R6M5F3 by doping with nitrogen (mass fraction of nitrogen from 0.05% to 0.10%). In this case, the designation marks — R6AM5 and R6AM5F3.

(Changed edition, Rev. N 2, 3, 4, 6).

1.2. In the finished product can be deviations in chemical composition specified in table.2.

Table 2

The name of the element	The mass fraction of the element in the Marche, %	Tolerance, %
Carbon	To 1.00 SV. Of 1.00	±0,01 ±0,02
Chrome	Within the standards table.1	±0,10
Tungsten	To 12.00 SV. 12,0 «15,00 «15,00	±0,10 ±0,15 ±0,20
Vanadium	Within the standards table.1	±0,05
Molybdenum	To 1.00 SV. Of 1.00	±0,03 ±0,05
Cobalt	To 0.50 SV. A 4.0 «5,00 «5,00	+0,05 ±0,10 ±0,15
Silicon	Within the standards table.1	+0,05
Manganese	The same	+0,05
Nitrogen	«	±0,01
Niobium	«	±0,02

(Changed edition, Rev. N 3, 4, 6).

2. ASSORTMENT

2.1. Steel are made in the form of bars and streaks.

2.2. The form, dimensions and limit deviations of the steel should meet the requirements:

hot rolled round and square sections, GOST 2590−88, GOST 2591−88;

forged GOST 1133−71;

strip — GOST 4405−75;

calibrated GOST 7417−75;

steel with special surface finish GOST 14955−77 with a diameter of from 1 to 25 mm inclusive.

2.1, 2.2. (Changed edition, Rev. N 2).

2.3. Metal products are divided as follows:

the macrostructure and carbide heterogeneity on group:

Group I (diameter or thickness from 80 to 200 mm),

Group II (diameter or thickness up to 150 mm);

by way of further processing into subgroups:

for hot forming,

 — for cold machining.

Examples of symbols:

Steel hot rolled round, the usual accuracy of rolling, with a diameter of 40 mm according to GOST 2590−88, stamps R18, group II, subgroups :

Steel grooved 18 mm diameter, quality according to GOST 7417−75, brand R6M5 electroslag remelting, surface quality group according to GOST 1051−73:

(Changed edition, Rev. N 3, 4, 6).

3. TECHNICAL REQUIREMENTS

3.1. The rods and strips are manufactured in accordance with the requirements of this standard for technological regulations approved in the prescribed manner.

(Added, Rev. N 3).

3.1. The hardness of the steel in the annealed condition, the hardness of the samples after quenching and tempering, the temperature of quenching and tempering must match the values specified in table.3.

Table 3

Steel grade	Hardness			Temperature, °C
	after annealing		after quenching with the release HRC(HRC), min.	hardening	holiday
	NV, not more than	indentation diameter, mm, not less
R18	255	3,8	63 (62)	1270	560
R6M5	255	3,8	64 (63)	1220	550
11R3AM3F2	255	3,8	64 (63)	1200	550
R6M5F3	Two hundred sixty nine	3.7 V	65 (64)	1220	550
R12F3	269	3.7 V	64 (63)	1250	560
R18K5F2	285	3,6	64 (63)	1280	570
R9K5	269	3.7 V	64 (63)	1230	570
R6M5K5	269	3.7 V	65 (64)	1230	550
R9M4K8	285	3,6	65 (64)	1230	550
R2AM9K5	285	3,6	65 (64)	1200	540

Notes:

1. Deviation from the given temperatures must not exceed ±10 °C.

2. Hardness values after quenching and tempering depending on the temperature of the leave is given in Annex 4.


On demand of the consumer steel grades R12F3, R9K5, R6M5F3, R6M5K5 is manufactured with a hardness not to exceed 255 HB (indentation diameter not less than 3.8 mm), steel stamps R18K5F2, R9M4K8 — with hardness not exceeding 269 HB (indentation diameter not less than 3.7 mm).

(Changed edition, Rev. N 3, 4, 5, 6).

3.2. In the macrostructure of steel not permitted: Pousada looseness, delamination, bubbles, inclusions and cracks.

Permitted defects of a macrostructure of not exceeding the values specified in table.3A.

Table 3A

Kind of defect	The diameter or thickness of metal, mm	Score, max, for groups
		I	II
Pousada liquation	All sizes	1	1
Central porosity	Up to 80	-	1
	SV. 80 to 150	1	2
	«150» 200	2	-
Dot spotted heterogeneity	Up to 50	-	1
	SV. 50 to 80	-	2
	«80» 150	1	2
	«150» 200	2	-

Standards of group I are provided with electroslag remelting.

(Changed edition, Rev. N 3, 4).

3.3. (Deleted, Rev. N 2).

3.4. (Deleted, Rev. N 6).

3.5. Carbide heterogeneity should not exceed the values given in table.4.

Table 4

Circle diameter or square side, mm	Score, max, for groups
	I	II
Up to 20	-	2
SV. 20 to 40	-	3
«40» 60	-	4
«60» 80	-	5
«80» 100	5	6
«100» 150	6	7
«150» 180	7	-
«180» 200	8	-

Carbide inhomogeneity of the strip should correspond to the carbide heterogeneity of the square cross-section with equal cross-sectional area.

Bars with special surface finish marks R6M5, R6M5F3, 11R3AM3F2, R9K5, R6M5K5, R2AM9K5 clusters «angular» carbides are not allowed. Permitted individual «angular» carbides, occurring in separate fields of view.

Standards of group I are provided with electroslag remelting.

(Changed edition, Rev. N 3, 4, 6).

3.5 a, 3.5 b (Deleted, Rev. N 3).

3.6. (Deleted, Rev. N 2).

3.7. Depth bezoperatsionnogo layer hot rolled, forged and calibrated steel shall not exceed per side:

0,3 mm 2% of diameter or thickness for diameters or thicknesses up to 20 mm;

0.5 mm plus 1% of the diameter or thickness for diameters or thicknesses exceeding 20 mm.

On the bars with special surface finish obesplozhennym layer is not allowed.

3.8. The ends of the rods and strips should be evenly cut or cut, without burrs and shavings.

The length of the folded ends should not exceed:

1.5 diameter or thickness for steel products of diameter or thickness up to 10 mm;

40 mm — for steel products with a diameter or thickness greater than 10 to 60 mm;

60 mm — for steel products with a diameter or thickness greater than 60 mm.

3.7, 3.8. (Changed edition, Rev. N 3).

3.9. On the surface of bars and strips of a subgroup should not be rolled and uninhibited bubbles, contaminations, cracks, stress and grinding, sunsets and sekulow, rolling captivity. Defects should be removed by gentle cutting or Stripping, the depth of which shall not exceed the tolerance on size. Allowed without Stripping some small risks, rabiza, fingerprints and other defects of mechanical origin with a depth not exceeding half of the dimension tolerance.

On the surface of bars and strip subgroup of permitted defects when their depth is determined by the control zapilovku, does not exceed the standards described in paragraph 3.7 (depth bezoperatsionnogo layer).

(Changed edition, Rev. N 3, 4).

3.10. The grooved surface of steel should meet the requirements of GOST 1051−73, steel with special surface finish — groups C, d, D GOST 14955−77.

Group surface finishes shall be specified in the order.

3.11. By agreement of the parties, and hot forged steel of circular section made provoslavnoy or honed surface.

On the surface glubokovodnykh or grinded bars permitted defects and decarburization not to exceed 25% of the standards specified in paragraph 3.7.

3.12. (Deleted, Rev. N 2).

3.13, 3.14. (Deleted, Rev. N 3).

3.15. Grain size of austenite steel after quenching must meet the specified in table.5.

Table 5

The diameter or thickness of metal, mm	Grain size of austenite is not larger rooms
	according to the method Sneijder-Graff	on a scale
Up to 50	13	10
SV. 50	10	9

(Added, Rev. N 3).

4. ACCEPTANCE RULES

4.1. Steel take parties.

The party must consist of one of metal smelting, the same group of the same size, the same subgroups and the same heat treatment.

Each batch is accompanied by a quality document in accordance with trebovaniyami 7566−94.

(Changed edition, Rev. N 3).

4.2. Surface quality check on all the bars and bands of the party.

4.3. To check the chemical composition of the selected one sample from melting, from the party of bars or stripes — single rod or strip.

4.4. Size — 10% rods, strips from the party, but at least five pieces.

4.5. To control the hardness of the annealed steel:

for steel products of diameter or thickness up to 30 mm taken in two bar or two bars from the 1 ton, but not less than eight bars or strips from the party; for steel products with a diameter or thickness greater than 30 mm 15% of bars from the party, but not less than five pieces or two strips from a 1 ton, but not less than five bands from the party.

4.3−4.5. (Changed edition, Rev. N 3).

4.6. To check the macrostructure — two rods, two plates or strips from the party.

4.7. (Deleted, Rev. N 6).

4.8. To check carbide inhomogeneity take two rods, two strips from the party.

4.9. To check the depth bezoperatsionnogo layer — two bars or two bars from the party.

Bars with a diameter and thickness greater than 100 mm in the decarburization is not allowed to control.

4.10. To check the hardness after quenching with vacation and the grain size of the austenite — single rod or one strip from the party, but at least two from the melting.

4.9−4.10. (Changed edition, Rev. N 3).

4.11. If unsatisfactory test results of at least one of the indicators of carried out the test according to GOST 7566−94.

4.12. Carbide heterogeneity, macrostructure and hardness after quenching and tempering of bars with a diameter or thickness up to 40 mm inclusive is ensured by the fabrication technology.

(Changed edition, Rev. N 1, 6).

4.13. (Deleted, Rev. N 3).

5. TEST METHODS

5.1. The selection and preparation of samples for determining the chemical composition of the steel should be carried out according to GOST 7565−81, chemical analysis according to GOST 12344−88, 12345−2001 GOST, GOST 12346−78, 12347−77 GOST, GOST 12348−78, 12349−83 GOST, GOST 12350−78, 12351−81 GOST, GOST 12352−81, 12353−78 GOST, GOST 12354−81, 12355−78 GOST, GOST 12359−99, 12361−2002 GOST, GOST 28473−90 or other methods providing the required accuracy.

(Changed edition, Rev. N 1, 4, 5, 6).

5.2. Sizes of hot-rolled and forged steel check of the measuring tools and templates, and a calibrated steel and steel with special surface finish — micrometers or staples.

(Changed edition, Rev. N 2).

5.3. The hardness of the finished annealed steel test according to GOST 9012−59 after Stripping bezoperatsionnogo layer.

The test carried on one end of the rod or strip at a distance of approximately 100 mm from the end.

The number of prints should not be less than three. Each value of hardness shall be those specified in table.3.

5.4. Hardness after quenching and tempering is determined according to GOST 9013−59 on the samples taken from the finished profile. Control is performed on the plane perpendicular to the extrusion direction. The number of prints on each sample must not be less than three.

The heating temperature for quenching and tempering specimens shall conform to the values specified in table.3.

Cooling of samples after quenching is performed in oil.

Leave the samples is carried out two to threefold, with the extract for 1 h and air cooling.

The holding time at the heating set according to the features.1.

Damn.1

1 — for rectangular samples; 2 — for round samples

Damn.1

Scheme cutting, shape and dimensions of samples are shown in table.6A.

Table 6A

mm

Controlled feature	The diameter or thickness of wire	Scheme cutting, shape and size of the sample
Hardness after quenching and tempering Carbide heterogeneity Grain austenite	Up to 30
	SV. 30 to 60
	SV. 60

5.3, 5.4. (Changed edition, Rev. N 3).

5.5. Surface quality check steel without the use of magnifying devices. If necessary, the surface is pre-sanded rings or snake.

5.6. For testing at PP.4.5−4.10 from each selected unit cut off one template (sample).

One sample may be used for various types of tests.

5.7. Macrostructure of bars and stripes test without the use of magnifying devices according to GOST 10243−75 etching of the templates selected from ready-made metal or from an intermediate workpiece.

Evaluation of dot-spotted heterogeneity is carried out according to the scale given in Annex 2A.

5.6, 5.7. (Changed edition, Rev. N 3).

5.8. The control of the fracture is carried out by visual examination without the use of magnifying devices.

To control the fracture is subjected to a hardening of samples cut from the annealed finished metal.

5.9. Assessment of heterogeneity carbide rods and strips is carried out on the samples cut at a distance of not less than 30 mm from the shear zone under the end table.6A on a plane parallel to the extrusion direction, and angular carbides on the plane perpendicular to the extrusion direction.

Clipping samples for thin sections spend ways, excluding the crushing and bending of fibers in the monitored part of the specimen.

Samples in the form of sectors are subjected to hardening by mode, given in tab.3 for the tested steel grades, the release delayed at least 1 h at 680 °C — 700 °C after annealing and subsequent etching in a 4% strength solution of nitric acid in ethyl alcohol.

Allowed control of carbide heterogeneity on the samples after quenching from the temperature of 900 °C without a break, followed by etching in a 10% strength solution of nitric acid in ethyl alcohol.

Carbide heterogeneity depending on the cross-sectional shape of the steel should be controlled in accordance with the table.7.

Table 7

The cross sectional shape of steel	Control place
Round	In the middle of the radius
Square	0.25 side of the square from the middle of the side
Strip	0.25 thickness of the middle of the broad side

Evaluation of carbide heterogeneity is carried out by increasing (90−100). Clusters «angular» carbides in steel with special surface finish is evaluated by the increase (400−500).

Score carbide inhomogeneity is determined by comparison with standard scale N 1 — for steel grades R18, R12F3, R18K5F2, R9M4K8 and the scale N 2 — for steel of grade R6M5, R6M5F3, 11РЗАМ3Ф2, R9K5, R6M5K5, and R2AM9K5 in Annex 1.

Score a carbide heterogeneity of each cone is set as the arithmetic mean of the estimated worst five fields of view.

Note. If you receive a fractional score, the number that stands after the comma, less than or equal to 5, the rounding should be carried out in the direction of smaller score if more than 5 more points.


(Changed edition, Rev. N 2, 3, 4, 5, 6).

5.10. (Deleted, Rev. N 2).

5.11. Depth bezoperatsionnogo layer is determined according to GOST 1763−68. In case of disagreement in the quality assessment should use the method M2.

Depth bezoperatsionnogo layer of the steel strip must be measured along the wide side of the strip.

(Changed edition, Rev. N 6).

5.12. (Deleted, Rev. N 3).

5.13. The grain size of austenite is determined according to GOST 5639−82 method Sneijder-Graff or comparison with the standards for scale on hardened specimens cut according to table.6A so that the center match table.7. In case of dispute use method Sneijder-Graff.

Monitoring is carried out on plane sections perpendicular to the extrusion direction.

Samples subjected to quenching from temperatures indicated in the table.3. The holding time at the heating set according to the features.1, is given in section 5.4.

(Changed edition, Rev. N 6).

5.14. Allowed to apply statistical and non-destructive methods of control.

If there are differences in applied methods of control regulated by this standard.

(Added, Rev. N 3).

6. MARKING, PACKAGING, TRANSPORTATION AND STORAGE

6.1. Marking, packaging, transportation and storage GOST 7566−94 with the following additions:

steel obtained by electroslag remelting, additionally marked by the letter s: for example R6M5-sh;

bars with a diameter or thickness greater than 40 mm is subjected to 100% condom branding;

packaging steel with special surface finishing — according to GOST 14955−77, calibrated steel GOST 1051−73;

calibrated steel and steel with special surface finish should be stored in closed warehouses.

Sec. 6. (Changed edition, Rev. N 4).

APPENDIX 1. DESCRIPTION OF STANDARD SCALES OF HETEROGENEITY, CARBIDE, HIGH SPEED STEEL

ANNEX 1

Score	Description distribution carbide phase	The permissible width of the stripes or clusters of carbides, mm
		in vysokovoltnyh steels ( scale N 1)	in nizkovoltnoy and tungsten-molybdenum steels (an evaluation N scale 2)
1	Thin lamellar structure with short broken stripes	2	1
2	Banded structure, single or multiple distribution lines. Carbides within bands fragmented	4	2
3	A. Banded structure, single or multiple stripes. Carbides within bands fragmented	6	4
	B. Remnants of the broken carbide mesh. Mesh with crushed carbides	6	4
4	A. Banded structure. Single or multiple bands. Carbides within bands fragmented	8	5
	B. Weakly expressed in torn mesh with accumulations	8	5
5	A. Gruzopoluchatelja structure, single or multiple stripes	13	6
	B. pronounced the torn mesh with accumulations	13	6
6	A. Gruzopoluchatelja structure, single or multiple stripes	15	9
	B. pronounced the torn mesh meliorativnykh presence of cell clusters	15	9
7	The mesh is torn in some places and clusters	20	14
8	Multifariously torn mesh and clusters	25	18

Note. The band adopted a cluster of carbides, the length of which is greater than or equal to 5 times the width. Two adjacent strips are considered one if the distance between them is less than the width of the narrower strip.

Scale N 1 for the evaluation of carbide heterogeneity in high speed steels (increase 100_(x))

Scale N 1 for the evaluation of inhomogeneity of carbide high speed steel (magnification 100)

N scale 2 for the evaluation of carbide heterogeneity in high speed steels (increase 100_(x))

N scale 2 to assess the heterogeneity of the carbide high speed steel (magnification 100)

APPENDIX 1. (Changed edition, Rev. N 6).

APPENDIX 2. (Deleted, Rev. N 2).

ANNEX 2A — see tab.

ANNEX 2A (required). SCALE POINT-SPOTTED HETEROGENEITY OF HIGH-SPEED STEEL

ANNEX 2A
Mandatory

APPENDIX 3 (reference). PROPERTIES AND EXAMPLES OF APPLICATION OF HIGH-SPEED STEEL

APPENDIX 3
Reference

Mark	Viscosity	Wear resistance	The sanding behaviour	Red — vitality 59HRCwhen you vacation during the 4 h, °C	Special properties	Appointment
R18	Good	Good	Increased	620	Reduced tendency to overheat during hardening	For all kinds of cutting tools when machining carbon alloy structural steel
R6M5	Increased	Good	Good	620	Increased tendency to decarburization	Same as for steel R18, preferably for the manufacture of threading tools and tools, working with high impact loads
11R3AM3F2	Increased	Good	Reduced	620	Increased tendency to overheat during hardening	For simple-shaped tools when machining carbon and alloyed steels with strength not more than 784 MPa (80 kgf/mm)
R6M5F3	Good	Increased	Good	630	Increased tendency to decarburization	For finishing and semi-finishing tools (shaped cutters, reamers, broaches, milling cutters, etc.) when machining non-alloy and alloy structural steels
R12F3	Good	Increased	Reduced	630	Reduced tendency to overheat during hardening	For finishing tools in the processing of austenitic steel and a viscous material having abrasive properties
R18K5F2	Reduced	Increased	Good	640	Reduced tendency to overheat during hardening	For roughing and semi-finishing tools when machining high strength, stainless and heat resistant steels and alloys
R9K5	Reduced	Increased	Reduced	630	Reduced tendency to overheat during hardening	For machining stainless steels and heat-resistant alloys and steels
R6M5K5	Good	Increased	Good	630	Increased tendency to decarburization	For roughing and semi-finishing tools in the processing of improved alloyed and stainless steels
R9M4K8	Reduced	Increased	Reduced	630	Increased tendency to decarburization	Various types of tools when machining high strength, heat resistant and stainless steels and alloys, as well as improved alloy steels
R2AM9K5	Good	Good	Reduced	630	Increased tendency to decarburization and overheating during hardening	For cutting tools when machining improved alloyed and stainless steels

APPENDIX 3. (Changed edition, Rev. N 3, 4, 6).

ANNEX 4 (reference). CURVES OF HARDNESS FROM THE TEMPERING TEMPERATURE OF

ANNEX 4
Reference

Damn.2, 3, 5, 6

Damn.2*	Damn.3
Damn.5**	Damn.6

________________ * The numbering of the drawings match the original. — Note the CODE. ** Hell.4. (Deleted, Rev. N 6).

Hell.7, 8, 9, 10, 11, 12, 13

Damn.7	Damn.8
Damn.9	Damn.10
Damn.11	Damn.12
Damn.13

ANNEX 4. (Changed edition, Rev. N 3, 6).