Outstanding 945X Special Alloys For Petrochemical Industry High Strength Type

Outstanding Alloy 945X (Alloy 945, UNS N09945) bar, tube, forging, wire for chemical and petrochemical processing

1 PRODUCT

Outstanding Alloy 945X (Alloy 945, UNS N09945) bar, tube, forging, wire for chemical and petrochemical processing

Alloy 945 standard semi-product forms include round bar, hexagon bar, forging, ring, disc, tube, wire and fastener, etc.

2 EQUIVALENT DESIGNATION

Alloy 945, UNS N09945, Incoloy ® alloy 945®, Incoloy ® alloy 945X ®

3 OVERVIEW

Alloy 945X is an age hardenable nickel-iron-chromium alloy with additions of molybdenum, copper, niobium, titanium, and aluminum. The alloy chemical composition is designed to provide a combination of high strength and excellent corrosion resistance. The nickel content is sufficient to provide protection against chloride-ion stress corrosion cracking.

The nickel, in conjunction with the molybdenum and copper, also gives outstanding general corrosion resistance to reducing chemicals. The molybdenum aids resistance to pitting and crevice corrosion. The alloy’s high chromium content provides resistance to oxidizing environments. The niobium, titanium and aluminum are added to provide high volume fraction of sub-micron size uniformly distributed Ni (NbTiAl)-type gamma prime and Ni (TiNbAl)-type gamma double prime precipitates. Their precipitates are responsible for high strength of the alloy by virtue of a dispersion strengthening mechanism. A special precipitation hardening (age hardening) heat treatment is developed to provide required strength.

4 APPLICATION

Alloy 945X is suitable for various applications requiring a combination of high strength and corrosion resistance. Because of the alloy’s resistance to sulfide stress corrosion cracking and stress corrosion cracking in H₂S containing environments, the alloy has been used in oil and natural gas components for down-hole and surface gas-well including SSSV, MWE/LWD tools, liner hangers, packers, components for BOPs and more. One of the primary uses of alloy 945X is OCTG and coupling stock. Further, the alloy is suitable to use in landing nipples, tool joints, gas lift, fasteners, pump shafting and high strength piping systems.

5 CHEMICAL COMPOSITION (wt%):

6 PHYSICAL PROPERTIES

Density: 0.298 lbs/in³ / 8.265 g/cm³

Melting range: 2323 - 2424°F / 1273 - 1329°C

Electrical resistivity, 682 ohm.cmil/ft / 1.10 ΜΩ-m

Permeability at 200 oersteds (15.9 kA/m) = 1.002

Young’s modulus, 29.4 x 10⁶ psi 29.4 / 202.7 GPa

7 MECHANICAL PROPERTIES

Limiting mechanical properties of annealed + aged Alloys 945, 945X and 925

Limiting mechanical properties of annealed, cold drawn, and aged shaft-grade alloy 945 and 945X bar

8 CORROSION RESISTANCE

Concentrations of Nickel, Chromium, Molybdenum, and Copper are optimized to provide excellent corrosion resistance in oil and gas environments for Galvanically - Induced Hydrogen Stress Cracking (GHSC), Sulfide Stress Cracking (SSC), and Stress Corrosion Cracking (SCC).

9 WORKING INSTRUCTION

Hot working

Alloy 945X can be hot and cold worked similar to other conventional Ni-base super alloys. Hot working range of Alloy 945X is 1700°F to 2100°F (930°C to 1150°C). Hot working characteristics of Alloy 945X are very similar to alloy 718.

Cold working

Alloy 945 can be easily cold worked for up to 40% cold work. Figure 1 shows the work hardening curve of alloys 945, Alloy K-500, 304 stainless steel, and alloy 718. The work hardening rate of alloy 945 is similar to that of alloy K-500.

Figure 1 Work hardening rate of various alloys

Machinability

Alloy 945X is an age hardenable alloy with good machinability in solution annealed or aged conditions. Rigid tools with positive rake angles and techniques that minimize work hardening of the material are required. Best results are obtained by rough machining before age hardening and finishing after heat treatment. Machinability of alloy 945X is comparable to alloy 718.

Annealing

Alloy 945X can be annealed in the temperature range of 1750°F to 1950°F (954°C to 1066°C). For best microstructure and properties the alloy should be annealed in the range of 1850°F (1010°C) to 1950°F (1066°C).

Figure 2 shows grain size and hardness versus annealing temperature.

A plot of grain size versus annealing temperature for a number of different mill products is shown as Figure 3.

Figure 2 Hardness and grain size versus annealing temperature for alloy 945 and 945X

Figure 3 Grain size versus annealing temperature of alloy 945. The data showing a band of grain size is generated using various product forms.

Age hardening

1300°F-1350°F (704°C-732°C) / 6-8 hours, furnace cool 50°F-100°F (26-56 °C) / h to 1125°F -1175°F (607°C –635°C), hold at this temperature for 6-8 hours, air cool.

Figure 4 Age hardening of Alloy 945. The material was annealed and exposed at the aging temperature for 8 hours

11 STANDARD SPECIFICATION

Based on extensive corrosion testing, Alloy 945X has been incorporated in in oil and gas applications by NACE MR0175 / ISO-15156-3 for up to NACE level VII at max hardness level of 42Rc and to level VI-450ºF.

12 COMPETITIVE ADVANTAGE

(1) More than 50 years experience of research and develop in high temperature alloy, corrosion resistance alloy, precision alloy, refractory alloy, rare metal and precious metal material and products.
(2) 6 state key laboratories and calibration center.
(3) Patented technologies.

(4) Ultra-purity smelting process: VIM + IG-ESR + VAR

(5) Excellent high performance.

13 BUSINESS TERM