H48T | Paralloy Group | Paralloy Group

28/48/5 Cr/Ni/W 0.5%C

Cast Heat Resisting Alloy

Application

Established Tungsten Strengthening Alloy For High Temperature

H48T may be used in applications up to 1200ºC in conditions where the maximum resistance to carburisation and oxidation are required. For example, applications for this alloy include: pyrolysis hangers, furnace rollers, radiant tubes and retorts, and heat treatment furnace components such as trays and fixtures. H48T is also used for catalyst tubes in high temperature reformer furnaces such as hydrogen furnaces in direct reduction plants, which operate over 1000ºC.

H48T is a weldable chromium-nickel heat-resisting steel containing 28% Cr and 48% Ni and further alloyed with a tungsten addition. The result is an alloy which displays an excellent combination of creep strength along with resistance to carburisation and oxidation at high temperatures up to 1200ºC. The alloy is readily welded by the standard metal arc (SMAW) welding processes using matching composition type electrodes.

Nominal Composition

6
C Carbon

0.4
14
Si Silicon

1.6
25
Mn Maganese

1
24
Cr Chromium

35
28
Ni Nickel

45
43
Nb Niobium

1
Plus
Additions

Physical Properties

Coefficient of Thermal Expansion (mm/mm°C)	Thermal Conductivity (W/m°K)	Density (kg/m³)	Young Modulus (N/mm² x 103)	Specific Heat (J/KgK)
20 – 100°C – 15.6 x 10⁻⁶	100°C – 13.8	7.97 x 10³	20°C – 176.5	480
20 – 800°C – 18.8 x 10⁻⁶	800°C – 25.9		800°C – 127.2
20 – 1000°C – 19.2 x 10⁻⁶	1000°C – 28.3		1000°C – 109.1
20 – 1100°C – 19.5 x 10⁻⁶	1100°C – 31.5

Mechanical Properties

Download specifications

UTS (N/mm²) 450
Proof Stress 0.2% (N/mm²) 250
Elongation (%) 4

Temp (°C)	10,000 Hour Life		50,000 Hour Life		100,000 Hour Life
	Minimum	Mean	Minimum	Mean	Minimum	Mean
950	22.08	26.07	17.59	20.76	15.83	18.68
975	18.63	21.99	14.49	17.1	12.9	15.23
1000	15.5	18.29	11.76	13.88	10.36	12.23
1025	12.71	15.01	9.41	11.11	8.19	9.67
1050	10.28	12.14	7.41	8.75	6.38	7.54
1075	8.2	9.68	5.76	6.8	4.9	5.78
1100	6.45	7.62	4.41	5.2	3.7	4.37
1125	5.01	5.91	3.32	3.92	2.76	3.26
1150	3.83	4.52	2.47	2.91	2.02	2.39

Download specifications

UTS (N/mm²)	450
Proof Stress 0.2% (N/mm²)	250
Elongation (%)	4

Temperature (°C)	UTS (N/mm²)	0.2% (N/mm²)	Elongation (%)
820°C	226	106	30
950°C	175	67	36
1050	113	41	44
1150	59	28	47

Temp (°C)	10,000 Hour Life		50,000 Hour Life		100,000 Hour Life
	Minimum	Mean	Minimum	Mean	Minimum	Mean
950	22.08	26.07	17.59	20.76	15.83	18.68
975	18.63	21.99	14.49	17.1	12.9	15.23
1000	15.5	18.29	11.76	13.88	10.36	12.23
1025	12.71	15.01	9.41	11.11	8.19	9.67
1050	10.28	12.14	7.41	8.75	6.38	7.54
1075	8.2	9.68	5.76	6.8	4.9	5.78
1100	6.45	7.62	4.41	5.2	3.7	4.37
1125	5.01	5.91	3.32	3.92	2.76	3.26
1150	3.83	4.52	2.47	2.91	2.02	2.39