Steel 15K

Designation

Name	The value
Designation GOST Cyrillic	15К
Designation GOST Latin	15K
Transliteration	15K
By chemical elements	15

Description

15K steel is used: for the manufacture of flanges, bottoms, one-piece forged and welded drums of steam boilers, buildings vehicles and other parts of the boiler and vessels working under pressure at temperatures up to +450 °C.

Note

In accordance with GOST 5520−79 with 01.01.1991 steel stamps 12K is not allowed to use in the newly created and upgraded technology.

Standards

Name	Code	Standards
Sheets and strips	В23	GOST 5520-79, GOST 19903-74, GOST 19903-90

Mechanical properties

Section, mm	s_T\|s_0,2, MPa	σ_U, MPa	d₅, %	y, %	KCU, kJ/m²
Steel hot-rolled sheet in the delivery condition
21-40	≥220	≥380	≥25	-	≥735
Leaves categories: 2-4, 10, 16, 18-21 (KCU - as supplied / after mechanical aging)
≤5	≥225	370-480	≥27	-	-
21-40	≥215	370-480	≥26	-	≥637/294
41-60	≥205	370-480	≥25	-	≥686/294
5-20	≥225	370-480	≥27	-	≥686/343
Casting as supplied. Without heat treatment
-	≥200	≥400	≥24	≥35	≥490
Sheet gracieacademy (specified time and temperature of exposure)
-	≥225	≥370	≥33	≥74	-
-	≥180	≥350	≥34	≥73	-
Sheets hot rolled 37-40 mm
-	≥225	≥420	≥30	≥56	-
-	≥195	≥390	-	-	-
-	≥195	≥470	-	-	-
-	≥165	≥470	-	-	-
-	≥160	≥370	-	≥60	-
-	≥155	≥250	-	≥61	-
Sheets hot rolled 37-40 mm. Annealing at 880-900 °C
-	≥245	400-430	≥30	55-60	-
-	180-225	350-500	17-28	43-62	-
-	145-185	350-510	≥24	52-60	-
-	140-175	320-400	22-33	60-73	-
-	120-150	200-270	24-33	71-83	-
-	69-98	110-150	36-48	84-91	-

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

Physical characteristics

Temperature	Е, HPa	G, HPa	r, kg/m³	l, W/(m · °C)	R, Mr. · m	a, 10^-6 1/°C	С, J/(kg · °C)
0	207	78	7850	-	-	-	-
20	211	-	7870	-	200	-	-
100	204	77	7840	57	219	-	486
200	201	76	7810	53	292	119	470
300	196	73	7780	-	381	128	483
400	187	69	7740	45	487	132	533
500	176	66	7710	-	601	136	525
600	162	59	7670	38	758	136	584
700	-	-	7630	-	925	-	571
900	-	-	7610	-	1135	-	703
1000	-	-	7550	-	1167	-	695
1100	-	-	7490	-	1194	-	691
800	-	-	-	-	1094	139	703
1200	-	-	-	-	1219	-	687

A description of the physical symbols

Name	Description
Е	The normal elasticity modulus
r	Density
l	Coefficient of thermal conductivity
R	UD. the resistivity

Technological properties

Name	The value
Weldability	Welded without any restrictions. The welding methods of SMAW, ADS under flux and gas protection.
Склонность к отпускной хрупкости	tend not
The temperature of forging	Start - 1260 °C, the end - 750 °C.
Flock-sensitive sensitivity	not sensitive
Machinability	In a normalized state in HB 121-126 and blower SB=390 MPa Kn TV.SPL.=1.50 Kn b.St.=1.35