Inconel 740H

1.Inconel 740H INTRODUCTION

A nickel-chromium-cobalt superalloy age  hardened by the precipitation of a gamma prime  second phase. Alloy 740H exhibits excellent high  temperature strength in the age-hardened  condition up to 1500°F (815°C). With its high  contents of chromium and cobalt, alloy 740H  offers excellent resistance to oxidation,  carburization and sulfidation at elevated  temperatures. Alloy 740H is targeted for use  as advanced power production boiler tubes.

2.Inconel 740H STANDARD  PRODUCT FORMS

Bar, seamless tubes.

3.Inconel 740H LIMITING CHEMICAL  COMPOSITION, %

Nominal

C.................... 0.03 

Ni............ Balance 

Cr................... 25.0 

Mo....................0.5 

Co.................. 20.0

Al ......................1.0 

Ti ......................1.8 

Nb ....................2.0 

Mn................. 0.30 

Fe.....................0.7 

Si......................0.5

4.Inconel 740H PHYSICAL CONSTANTS  AND THERMAL  PROPERTIES

Density, Ib/in3 .........................................................................0.291 

g/cm3 ......................................................................... 8.05 

Melting Point, °F.....................................................2350 – 2484

°C.....................................................1288 – 1362 

Specific Heat, Btu/lb •°F....................................................0.108 

J/kg •°C.......................................................... 449 

Electrical Resistivity, ohm • circ mil/ft..........................702.7 

μΩ•m..............................................1.168 

Thermal Conductivity, Btu • in/ft2• h•°F.......................... 72.9 

W/m•°C.......................................... 10.2 

Coefficient of Expansion, 10-6 in/in•°F (μm/m•°C) 

70-200°F (21–93°C)..................6.84 (12.38) 

Young’s ModulusA , 103  psi........................................................32 

GPa .......................................................... 221 

Shear’s ModulusA , 103  psi.................................................... 11.5

GPa..............................................................79 

Poisson’s RatioA...................................................................... 0.35 

Magnetic Permeability .................................................... <1.005 

A Room temperature, as aged.

5.Inconel 740H TYPICAL MECHANICAL  PROPERTIES

Yield Strength, Room Temperature, Aged, ksi.................111 

Tensile Strength, Room Temperature, Aged, ksi.............170

Elongation, Aged, %................................................................... 36