UNS R30783 （ Inconel 738LC ）
Material grades and equivalents：Inconel 738LC / UNS R30783
UNS R30783 (Inconel 738LC), is an oxidation-resistant, low expansion, nickel-cobalt-iron alloy with aluminum, chromium, and niobium additions.
The new alloy is of considerable interest to aircraft gas turbine engine designers and materials engineers for containment and clearance control components such as rings, casings, shrouds and seals for compressors, turbines and exhaust systems. The three-phase age hardenable alloy offers a range of improvements for these applications over alternative alloys in current use: A coefficient of thermal expansion approximately 20% lower than that of INCONEL alloy 718.
Excellent resistance to oxidation, demonstrated in cyclic tests, at temperatures up to and beyond 1300 F (704 C). Resistance to SAGBO (stress accelerated grain boundary oxidation) comparable to that of INCONEL alloy 718, and significantly better than that of INCOLOY alloy 909. A density of 0.282 lb/in3 (7.81 g/cm3), 5% less than INCONEL alloy 718 or INCOLOY alloy 909, contributing to an important potential improvement in strength-to-weight ratios. Manufacturing/processing characteristics comparable to those of INCONEL alloy 718, and less limiting than those of INCOLOY alloy 909. Special Metals INCONEL alloy 783 is available as forging billet (AMS 5940), rod and bar for machining, extruded section, and wire rod. Sheet product is currently under development.
Inconel 738LC Chemical composition:
Element
|
C
|
Mn
|
Si
|
W
|
S
|
P
|
Cr
|
Mo
|
Ai+Ti
|
Min
|
0.09
|
–
|
–
|
2.4
|
–
|
–
|
15.7
|
1.5
|
6.5
|
Max
|
0.13
|
0.2
|
0.3
|
2.8
|
0.015
|
0.015
|
16.3
|
2.0
|
7.2
|
Element
|
Cb
|
Ti
|
Ai
|
B
|
Zr
|
Co
|
Ta
|
Fe
|
Ni
|
Min
|
0.6
|
3.2
|
3.2
|
0.007
|
0.03
|
8.0
|
1.4
|
–
|
Balance
|
Max
|
1.1
|
3.7
|
3.7
|
0.012
|
0.08
|
9.0
|
2.0
|
0.35
|
Heat Treatment Procedure:
Physical properties:
Precipitation Hardening
|
Solution Annealing
|
Temperature
|
Holding time
|
Remarks
|
1120 oC
|
2 hours
|
25-40 oC ⁄ min to below 800 oC
|
Aging
|
Temperature
|
Holding time
|
Remarks
|
845 oC
|
24 hours
|
Air cool
|
Tensile Property:
Temperature(℃)
|
Yield, N/mm2min
|
UTS, N/mm2min
|
Elongation, minA5 (%)
|
Reduction ofArea, min (%)
|
25
|
792
|
895
|
4
|
5
|
650
|
690
|
895
|
4
|
5
|
Creep Rupture Properties:
Temperature (℃)
|
Stress (N/mm2)
|
Life (Hours)
|
Elongation (A4) (%)
|
Reduction of Area (Z)(%)
|
982
|
152
|
≥ 30
|
≥ 5
|
≥ 10
|
