Steel 07KH16N4B

Designation

Name	The value
Designation GOST Cyrillic	07Х16Н4Б
Designation GOST Latin	07X16H4B
Transliteration	07H16N4B
By chemical elements	07Cr16Н4Nb

Description

07KH16N4B steel is used: for the production of forgings used in the manufacture of parts in shipbuilding and ship repair; forgings and stampings highly loaded parts products marine engineering; welded components of nuclear power equipment and chemical industries.

Note

High-alloy steel high-strength corrosion-resistant martensitic class.

Standards

Name	Code	Standards
Processing of metals by pressure. Forgings	В03	GOST 25054-81, OST 5Р.9125-84, ST ЦКБА 010-2004
Classification, nomenclature and General rules	В30	GOST 5632-72
Blanks. Of the workpiece. Slabs	В31	OST 3-1686-90, OST 95-10-72, TU 14-1-3570-83, TU 14-1-1564-76, TU 14-132-176-89
Thermal and thermochemical treatment of metals	В04	ST ЦКБА 016-2005
Bars and shapes	В32	TU 14-1-3573-83, TU 14-11-245-88, TU 14-1-5208-93
Castings with special properties (iron and steel)	В83	TU 5.961-11131-79, TU 5.961-11191-81

Chemical composition

Standard	C	S	P	Mn	Cr	Si	Ni	Fe	Cu	V	Ti	Mo	Nb	W
TU 14-1-3573-83	0.05-0.1	≤0.02	≤0.025	0.2-0.5	15-16.5	≤0.6	3.5-4.5	Rest	≤0.2	-	-	-	0.2-0.4	-
OST 5Р.9125-84	≤0.1	≤0.02	≤0.025	0.2-0.5	15-16.5	≤0.6	3.5-4.5	Rest	≤0.2	-	-	-	0.2-0.4	-
TU 14-132-176-89	0.05-0.1	≤0.02	≤0.025	0.2-0.5	15-16.5	≤0.6	3.5-4.5	Rest	≤0.3	-	-	-	0.2-0.4	-
GOST 5632-72	0.05-0.1	≤0.02	≤0.025	0.2-0.5	15-16.5	≤0.6	3.5-4.5	Rest	≤0.3	≤0.2	≤0.2	≤0.3	0.2-0.4	≤0.2

Fe is the basis.
According to TU 14-1-3573-83, the chemical composition is given for steel grades 07Х16Н4Б and 07Х16Н4Б-Ш. The steel is smelted on a high-purity charge billet 22RU. The content of impurities of non-ferrous metals should be no more than: tin - 0.0040%, arsenic 0.0080%, lead 0.0050%, zinc 0.0040%, antimony 0.0040%, bismuth 0.00010% . The following maximum deviations in the content of elements in steel are allowed in finished products: by chroma ± 0.10%, by nickel ± 0.050%, by carbon and niobium ± 0.010% each, by silicon and manganese +0.020% each. The residual content of the elements is in accordance with GOST 5632. When steel is smelted, the addition of ferroboron by 0.0030% boron by calculation and chemical analysis is not determined.
According to TU 14-1-3570-83, the chemical composition is given for steel grades 07Х16Н4Б and 07Х16Н4Б-Ш. The steel is smelted on a high-purity charge billet 22RU. The content of impurities of non-ferrous metals (tin, arsenic, lead, zinc, antimony, bismuth) should not exceed 1 point for each element. The following maximum deviations in the content of elements in steel are allowed in finished products: by chroma ± 0.10%, by nickel ± 0.050%, by carbon and niobium ± 0.010% each, by silicon and manganese +0.020% each. The residual content of the elements is in accordance with GOST 5632. When steel is smelted, the addition of ferroboron by 0.0030% boron by calculation and chemical analysis is not determined.
According to OST 5P.9125-84, the total mass fraction of Nb + Ta = 0.20-0.40% (specified in the value for Nb).
According to TU 14-132-176-89 the chemical composition is given for steel grade 07H16N4B. Tolerances in chemical composition are permissible in steel: carbon ± 0.010%, nickel ± 0.050%, phosphorus +0.0030%, chromium ± 0.10%, silicon +0.020%, manganese +0.020%, niobium ± 0.010%. Permissible deviations in chemical composition and content of residual elements are in accordance with GOST 5632. The mass fraction of vanadium is determined by chemical analysis and the results are entered into the certificate - the content of vanadium is optional.

Mechanical properties

Section, mm	t отпуска, °C	s_T\|s_0,2, MPa	σ_U, MPa	d₅, %	y, %	KCU, kJ/m²	HB, MPa	HRC
Blank pieces of pipe fittings according to ST CKBA 016-2005 steel 07KH16N4B (07KH16N4B-W). Quenching in oil with 1040-1060 °C + Vacation at 275-300 °C, air cooling
≤200	-	≥931	≥1029	≥10	≥45	≥784	302-351	-
200-300	-	≥735	≥882	≥13	≥50	≥833	269-302	-
300-400	-	≥686	≥882	≥13	≥50	≥833	269-302	-
400-500	-	≥686	≥882	≥12	≥40	≥833	269-302	-
Billets of steel grades 07KH16N4B and 07KH16N4B-sh (forgings) OST 95-10-72. Quenching in oil with 1040-1060 °C + Vacation, air cooling (samples)
≤180	620-660	≥735	≥882	≥13	≥50	≥588	248-302	20-30
≤100	270-310	≥883	≥1029	≥10	≥45	≥588	302-375	30-38
Forgings for parts resistant to the ICC. Quenching in oil with 1040-1060 °C, cooled to 70-90 °C + Vacation at 640-660 °C (first stage) air cooling + Vacation at 610-630 °C (stage II) air cooling
500	-	≥690	≥882	≥12	≥40	≥558	269-302	-
Bars hot rolled and forged on the other 14-1-3573-83, THE 14-1-3570-83. The longitudinal samples. Quenching in oil with 1040-1060 °C (exposure 1-2 min/1mm section) + Vacation at 640-660 °C (exposure 2 hours), air cooling
25-30	-	≥735	≥880	≥13	≥50	≥883	-	-

Description mechanical marks

Name	Description
s_T\|s_0,2	Yield strength or limit of proportionality with a tolerance for residual deformation of 0.2%
σ_U	Limit short-term strength
d₅	Elongation after rupture
y	The relative narrowing
KCU	Toughness
HB	Brinell hardness number
HRC	Rockwell hardness (indenter diamond spheroconical)

Technological properties

Name	The value
Macrostructure and pollution	Macrostructure of steel, when checking on the etched templeto should not have shrinkage looseness, bubbles, captivity, cracks, fistulas and slag inclusions. The metal of the electroslag remelting allowed layer-by-layer crystallization and the light circuit is not more than the 3rd point of the scale GOST 10243. Pollution steel non-metallic inclusions shall not exceed the following standards for maximum grade: for steel 07KH16N4B-W - Oxides (OS, OT), silicates (CX, SP) and sulfides (S) 2, silicates, non-deformed (SN) not more than 2.5, nitrides and carbonitrides - not more than 3.5; for steel 07KH16N4B - Oxides (OS, OT), silicates (CX, SP) and sulfides (s) is not more than 3, silicates, non-deformed (SN) - not more than 3.5, nitrides and carbonitrides - no more than 4.
Features of heat treatment	To obtain characteristic values of mechanical properties and hardness set ST CKBA 010 and to achieve maximum corrosion resistance, parts (workpiece) valves shall be subjected to hardening and tempering. The heating of the parts (workpieces) in the temperature range from 500 °C to 800 °C must be carried out at a speed of not more than 200 °C per hour. In the temperature range 750 - 800 °C it is necessary to give exposure to the full heating of the charge. Further heating to the quenching temperature produced by the furnace. For parts with thickness (diameter) up to 120 mm the rate of heating is not limited and aging at a temperature of from 750 °C to 800 °C is not possible. The time between quenching and the beginning of vacation - less than 3 hours. Welded components and steel products 07KH16N4B (07KH16N4B-sh) to improve the corrosion resistance subjected to annealing according to one of the modes. 1 mode: Heating to 640-660 °C, exposure - 3-4 min/mm thickness but not less than 5 h, air cooling (in the presence of a welded Assembly of parts made of steel 14KH17N2 hardfacings cooling of the welded Assembly after annealing is performed with the furnace or with the furnace to 300 °C, and then to the air). Mode is used for parts operating at temperatures up to 100 °C. 2 mode: Heating up to 670-680 °C, exposure - 3-4 min/mm thickness but not less than 5 h, air cooling or Heating to 600-620 °C, exposure - 3-4 min/mm thickness but not less than 2 h, air cooling. Mode is used for parts operating at temperatures up to 100 °C.
Machinability	To improve the machinability and the hardness HB ≤ 269 workpiece is subjected to annealing at 630-650 °C for 4-8 h with air cooling.
The tendency to intergranular corrosion	Steel must be resistant to intergranular corrosion.