Incoloy 901

ALLOY 901 TECHNICAL DATA

Type Analysis

Element	Min	Max
Nickel + Cobalt	40.0	45.0
Chromium	11.0	14.0
Silicon	--	0.40
Sulfur	--	0.03
Cobalt	--	1.00
Iron	Remainder
Aluminum	--	0.35
Carbon	--	0.10
Manganese	--	0.50
Molybdenum	5.00	6.50
Titanium	2.80	3.10
Copper	--	0.50

Description

A nickel-iron-chromium alloy containing titanium and aluminum for precipitation hardening and molybdenum for solid-solution strengthening. The alloy has high yield strength and creep resistance at temperatures to about 1110°F (600°C). A substantial iron content enables the alloy to combine high strength with good forging characteristics. Used in gas turbines for discs and shafts. Standard products form is round.

Corrosion Resistance

Alloy 901 has good corrosion resistance to the atmospheres normally found in jet engine operations. It has slightly lower scaling resistance than such alloy as Types 309 and 310 stainless steel.

Heat Treatment

Solution Treatment
1975/2025°F (1080/1107°C), hold 2 hours at heat, and water quench.

Stabiliztion Treatment
1400/1475°F (760/802°C), hold 2 to 4 hrs, and air cool.

Precipitation Hardening Treatment
1300/1375°F (704/746°C), hold for 24 hours, and air cool.

Workability

Hot Working
Alloy 901 is forged between 2050°F (1121°C) and 1850°F (1010°C), metal temperature. Light hot work may be continued down to 1600°F (871°C) but not below. Metal temperature should not exceed 2050°F (1121°C) during rapid working. Billets should be charged into a hot furnace and heated rapidly through the precipitation hardening range.

Weldability
Alloy 901 can be welded by the inert-gas-arc method. It is difficult to weld. All welding should be done in the solution treated condition. Cold worked parts should be re-solution treated before welding. A re-solution treatment is recommended after welding before stabilizing and aging.

Typical Mechanical Properties

Tensile Properties
Solution Treated: 2000°F (1093°C), 2 hours, water quenched. Stabilized: 1425°F (774°C), 4 hours , air cooled. Aged: 1350°F (732°C), 24 hours, air cooled.

Test Temperature		0.2% Offset Yield Strength		Ultimate Tensile Strength		% Elongation in 2"	% Reduction of Area
°F	°C	ksi	MPa	ksi	MPa	% Elongation in 2"	% Reduction of Area
70 800 1000 1200 1300 1400 1500	21.1 427 538 649 704 760 816	125.0 116.5 113 117 114 102.5 79	862 803 779 807 786 707 545	175 159 156 150 130 107.5 81	1207 1096 1076 1034 896 741 559	15.0 16.0 17.0 14.0 11.5 9.0 13.0	19.0 25.5 29.0 21.0 15.5 14.5 20.0

Stress Rupture Strength
Solution Treated: 2000°F (1093°C), 2 hours, water quenched. Stabilized: 1425°F (774°C), 4 hours , air cooled. Aged: 1350°F (732°C), 24 hours, air cooled.

Test Temperature		Stress to Produce Rupture in
°F	°C	10 Hours		100 Hours		1000 Hours
		ksi	MPa	ksi	MPa	ksi	MPa
1000 1200 1350 1500	538 649 732 816	-- 96.5 60 35	-- 665 414 241	120 90 51 22.5	827 621 352 155	100 75 33 11	689 517 228 76

Physical Properties

Density, lb/cu in.......................................................................... 0.294
              Mg/cu m.......................................................................... 8.14
Melting Range, °F............................................................... 2335-2455
                          °C............................................................... 1280-1345
Specific heat, Btu/lb-°F................................................................ 0.103
                       J/kg-°C..................................................................... 431
 Permeability at 200 oersted (15.9 kA/m)......................................1.013
 Coeffiecent of Expansion,  68-212°F, 10(-6) in/in-°F................... 7.50
                                             20-100°C, æm/m-°C......................... 13.50
 Electrical Resistivity, ohm-cir mil/ft............................................... 674
                                     æê-m........................................................... 1.12