Overview

INCONEL alloy X-750 (UNS N07750/W. Nr. 2.4669)is a precipitation-hardenable nickel-chromium alloy used for its corrosion and oxidation resistance and high strength at temperatures to 1300°F.

This nickel alloy exhibits high creep-rupture strength at elevated temperatures to about 130.0°F (700°C). It also has excellent properties down to cryogenic temperatures. The alloy maintains high strength at high temperature, resists corrosion and has good oxidation resistance at up to 1300°F. Inconel X 750 is resistant to chemical corrosion, showing resistance to a wide variety of industrial corrosives under both oxidizing and reducing conditions. This alloy also has excellent resistance to chloride stress corrosion cracking in the fully age hardened condition. This Inconel alloy can be strengthened by precipitation treating after hot or cold working or by precipitation hardening after equalizing or solution treating.

Limiting Chemical Composition, %

Nickel (plus Cobalt)...............................................................................................................................................................70.00 min.

Chromium............................................................................................................................................................................14.00-17.00

Iron...........................................................................................................................................................................................5.00-9.00

Titanium..................................................................................................................................................................................2.25-2.75

Aluminum................................................................................................................................................................................0.40-1.00

Niobium (plus Tantalum).......................................................................................................................................................0.70-1.20

Manganese.............................................................................................................................................................................1.00 max.

Sulfur.......................................................................................................................................................................................0.01 max.

Silicon......................................................................................................................................................................................0.50 max.

Copper.....................................................................................................................................................................................0.50 max.

Carbon.....................................................................................................................................................................................0.08 max.

Cobalt.......................................................................................................................................................................................1.00 max.

Physical Constants

Below are some physical constants and thermal properties of INCONEL alloy X-750

Mechanical properties

INCONEL alloy X-750 may be given any one of a variety of heat treatments. Each develops special properties and puts theproduct form in the best condition for its intended application. In all conditions, alloy X-750 is resistant to oxidation up to 1800°F. The most often used heat treatments have been incorporated by the Society of Automotive Engineers in their AMS specifications* for various product forms.

Tensile-properties

Corrosion Resistance

Alloy X-750 has excellent resistance to chloride ion stress-corrosion cracking. It exhibits satisfactory resistance to numerous oxidizing environments. The alloy has similar corrosion resistance to alloy 600 in many media.INCONEL alloy X-750 is resistant to a wide variety of industrial corrosives under both oxidizing and reducing conditions. It resists oxidation and attack by other hightemperature corrosion mechanisms.

In hot corrosion tests for automotive applications, weight loss after exposure for 100 hours in 90% Na2SO4 + 10% NaCl mixture in air was about 5%. Samples precoated with sodium chloride (by dipping in a hot saturated salt solution), suspended in a furnace at 1700°F and exposed for

100 hr to a moving gas stream of air containing 1% SO2 exhibited a corrosion penetration of approximately 0.007 in.

An interesting feature of this alloy is its high resistance to chloride-ion stress-corrosion cracking even in the fully precipitation-hardened condition. Standard U-bend specimens of precipitation-hardened material (hardness, 33 Rc) showed no signs of cracking when exposed to boiling 42% magnesium chloride for 30 days.

Heat Treatment

Alloy X-750 is austenitic under all conditions. The alloy is heat treated by several different methods depending upon the application or requirement. Two common treatments are:

1. For maximum creep, relaxtion and rupture strength at temperatures above 1100°F (593°C):

Solution Treatment - 1800°F (982°C), time commensurate with thickness, air cool.

Intermediate Age - 1550°F (843°C), 24 hrs, air cool.

Final Age -1300°F (704°C), 20 hrs, air cool.

2. For highest room temperature yield strength and tensile ductility:

Stress Equaliztation - 1625°F (885°C), 24 hrs, air cool.

Precipitation Age - 1300°F (704°C), 20 hrs, air cool.

Avaliable Forms

We provide you with a variety of product forms, including but not limited to

● Bar & Rod

● Pipe & Tube

● Coil & Strip

● Plate & Sheet & Circle

● Wire & Welding

● Fitting (Flange, Elbow, Tee...)

● Customize