Why Nickel Alloy 716 Round Bar Excels in High-Temperature Environments

Element	Content (%)	Function
Nickel (Ni)	50.0 – 55.0	Base metal, provides corrosion and oxidation resistance
Chromium (Cr)	17.0 – 21.0	Enhances oxidation and scaling resistance at high temperatures
Iron (Fe)	Balance	Adds toughness and structural stability
Molybdenum (Mo)	2.8 – 3.3	Improves resistance to localized corrosion (pitting and crevice)
Niobium (Nb) + Tantalum (Ta)	4.8 – 5.5	Strengthens alloy via precipitation hardening
Titanium (Ti)	0.6 – 1.15	Supports formation of gamma prime phase for heat resistance
Aluminum (Al)	0.2 – 0.8	Enhances oxidation resistance and precipitation hardening
Cobalt (Co)	≤ 1.0	Improves thermal stability
Carbon (C)	≤ 0.08	Strengthens grain boundaries
Sulfur (S)	≤ 0.015	Controlled to prevent cracking during forging or welding

This balanced chemistry enables Nickel Alloy 716 Round Bar to retain mechanical stability and resist high-temperature corrosion, making it a top choice for service in oxidizing and reducing atmospheres.

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Why Nickel Alloy 716 Performs Exceptionally Well at High Temperatures

1. Superior High-Temperature Strength

At elevated temperatures, most metals lose their structural integrity due to the breakdown of atomic bonds and the onset of creep deformation. However, Nickel Alloy 716 Round Bar retains exceptional strength due to its precipitation-hardening microstructure.

• Gamma Double Prime (Ni₃Nb) Phase: The primary strengthening phase that provides stability up to 700°C.

• Gamma Prime (Ni₃(Al, Ti)) Phase: Secondary phase that enhances creep resistance and prevents grain boundary sliding.

These precipitates act as barriers to dislocation motion, maintaining mechanical integrity even under continuous stress and heat.

Typical Mechanical Properties (at room temperature):

• Tensile Strength: 1250–1500 MPa

• Yield Strength: 900–1100 MPa

• Elongation: 12–20%

• Operating Temperature: Up to 700°C (1290°F)

At high temperatures, Nickel Alloy 716 maintains a significant portion of its room-temperature strength, far outperforming standard stainless steels or conventional nickel alloys.

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2. Exceptional Creep and Fatigue Resistance

Creep resistance — the ability to resist slow deformation under constant load at high temperature — is one of the most critical properties for materials used in turbines, reactors, and engines. Nickel Alloy 716 Round Bar provides superior creep resistance due to its fine-grained microstructure and stable precipitates.

• The alloy’s niobium and molybdenum content delays the onset of creep.

• Gamma prime and gamma double prime phases inhibit grain boundary movement.

• The microstructure remains stable even after thousands of hours of exposure to high temperatures.

This exceptional resistance to thermal degradation makes Nickel Alloy 716 a preferred choice for gas turbines, jet engines, and power generation equipment, where long-term exposure to high temperatures is inevitable.

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3. Excellent Oxidation and Scaling Resistance

Oxidation resistance is critical in high-temperature applications, as metal surfaces tend to react with oxygen and form scale, which can weaken components over time. Nickel Alloy 716 Round Bar contains chromium, aluminum, and nickel — elements that form a stable, protective oxide film that resists further oxidation.

• The chromium oxide layer (Cr₂O₃) protects the underlying metal from rapid oxidation.

• Nickel oxide (NiO) enhances stability under cyclic heating conditions.

• The alloy’s surface remains intact, reducing scaling and preventing material loss over extended use.

As a result, Nickel Alloy 716 Round Bar maintains its appearance, mechanical properties, and surface integrity even after continuous exposure to air, steam, and combustion gases.

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4. Thermal Stability and Microstructural Integrity

Thermal stability refers to a material’s ability to maintain its mechanical properties and microstructure after prolonged exposure to heat. Nickel Alloy 716 Round Bar exhibits excellent thermal stability due to the following factors:

• Stable Gamma Matrix: Prevents grain coarsening or phase transformation.

• Controlled Precipitate Distribution: The uniform dispersion of strengthening phases ensures consistent mechanical performance.

• Resistance to Thermal Fatigue: The alloy resists cracking and warping under cyclic temperature changes.

These characteristics make Nickel Alloy 716 especially reliable in applications involving frequent start-stop operations, such as turbines and compressors.

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5. Resistance to Hot Corrosion and Sulfidation

In many industrial environments — particularly oil refineries, gas turbines, and marine systems — components are exposed to sulfur-bearing gases and high-temperature salts that cause hot corrosion. Nickel Alloy 716 Round Bar resists these attacks due to its high nickel and chromium content, which form a protective oxide layer that blocks sulfur penetration.

Additionally, the alloy’s molybdenum content enhances resistance to pitting and crevice corrosion even under severe conditions involving molten salts or chlorides.

This resistance to hot corrosion makes Nickel Alloy 716 an ideal material for combustion chambers, exhaust systems, and chemical reactors that operate under aggressive high-temperature conditions.

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Heat Treatment and Hardening Process

The superior high-temperature performance of Nickel Alloy 716 Round Bar is enhanced through a controlled heat treatment process involving:

1. Solution Annealing (980–1010°C): Dissolves carbides and other segregated phases, creating a uniform solid solution.

2. Rapid Cooling: Quenching in air or water to retain the desired solid solution phase.

3. Aging (720–760°C): Promotes precipitation of strengthening phases (γ’ and γ”) that enhance strength and thermal stability.

This process ensures consistent mechanical performance, grain structure refinement, and dimensional stability across the entire bar length, making it suitable for precision machining and critical component fabrication.

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Applications of Nickel Alloy 716 Round Bar in High-Temperature Service

Because of its superior heat resistance and corrosion stability, Nickel Alloy 716 Round Bar finds use in a wide range of high-temperature applications, including:

1. Aerospace and Aviation

• Turbine disks and shafts exposed to jet exhaust temperatures

• Engine fasteners, afterburner components, and exhaust valves

• Combustion chambers and heat shields

2. Oil and Gas Industry

• Downhole tools and valve components for sour gas wells

• High-pressure tubing and subsea connectors

• Compressor blades and gas reinjection systems

3. Power Generation

• Steam and gas turbine blades

• Heat exchangers and boiler tubes

• Reactor core components in nuclear applications

4. Chemical Processing Plants

• Reactors, distillation towers, and acid-handling vessels

• Piping systems exposed to high-temperature acids and oxidizing environments

In all these applications, Nickel Alloy 716 Round Bar ensures reliable, long-term service life under continuous exposure to high heat and corrosive gases.

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Advantages of Nickel Alloy 716 Round Bar

• Outstanding high-temperature strength and creep resistance

• Excellent oxidation and hot corrosion resistance

• Superior fatigue performance under cyclic stress

• Stable mechanical properties over prolonged thermal exposure

• Ease of fabrication, welding, and machining

• Prolonged lifespan in harsh environments

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Why Choose SASAALLOY for Nickel Alloy 716 Round Bar

At SASAALLOY, we specialize in producing premium-quality Nickel Alloy 716 Round Bars that meet or exceed international standards for mechanical performance, heat resistance, and corrosion protection. Our production process includes vacuum induction melting (VIM) and electro-slag remelting (ESR), ensuring superior purity, microstructural consistency, and mechanical stability.

Every Nickel Alloy 716 Round Bar supplied by SASAALLOY undergoes stringent quality inspection, including ultrasonic testing, mechanical analysis, and corrosion testing, guaranteeing that each product performs flawlessly in high-temperature service.

Whether for aerospace components, power generation systems, or oil and gas projects, SASAALLOY delivers materials engineered for reliability, strength, and precision.

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Conclusion

The exceptional performance of Nickel Alloy 716 Round Bar in high-temperature environments stems from its unique metallurgical design, combining precipitation hardening, oxidation resistance, and thermal stability. This makes it one of the most versatile and dependable materials for industries where strength, durability, and reliability under extreme conditions are non-negotiable.

From jet turbines to subsea valves and chemical reactors, this alloy delivers long-lasting performance and exceptional resistance to both mechanical degradation and corrosive attack.

At SASAALLOY, we take pride in supplying Nickel Alloy 716 Round Bars of the highest quality, backed by precise manufacturing, rigorous testing, and unparalleled expertise. Choose SASAALLOY — your trusted partner for nickel-based alloys that push the limits of performance in the world’s toughest environments.