Waspaloy is a precipitation-hardenable, nickel-chromium-cobalt superalloy celebrated for its outstanding high-temperature performance. Its key characteristics are exceptional strength, creep resistance, and oxidation stability at temperatures up to 1800°F (980°C). This makes it indispensable in extreme environments.

The alloy's execution is strictly controlled by standards such as AMS 5708 for bars and forgings, and ASTM B637. For Waspaloy fastener products like bolts, nuts, and studs, these components are machined from certified stock and are produced to stringent aerospace standards like NAS and MS.

The primary application for Waspaloy fasteners is in the aerospace industry, specifically within the hot sections of gas turbine engines—including turbine casings, combustors, and compressor assemblies—where they must maintain clamping force under severe thermal and mechanical stress. They are also critical in industrial gas turbines for power generation and select high-temperature chemical processing equipment.

1. What is Waspaloy?

Waspaloy is a premier, high-strength, nickel-based superalloy. It is renowned for its exceptional combination of properties, including:

• High-Temperature Strength: It retains significant strength and resistance to creep (slow deformation under constant load) at temperatures up to about 980°C (1800°F).

• Excellent Oxidation Resistance: It forms a stable, protective oxide layer that prevents degradation in high-temperature environments.

• Good Corrosion Resistance: It performs well in various corrosive atmospheres.

• Superior Stress-Rupture Strength: It can withstand high stresses for long durations at elevated temperatures without failing.

These properties are achieved through a solid-solution strengthening mechanism (primarily from molybdenum and cobalt) and, most importantly, precipitation hardening from gamma prime (γ') phase [Ni₃(Al, Ti)].

2. What are the Execution Standards?

Waspaloy is governed by several international material and specification standards. The most common ones include:

• AMS (Aerospace Material Specification):

  • AMS 5708: This is the primary specification for bar, forgings, and rings used for high-temperature, high-strength applications.

  • AMS 5824: Covers welding wire and rod.

• ASTM (American Society for Testing and Materials):

  • ASTM B637: Standard specification for precipitation-hardening nickel alloy (UNS N07001) bars, forgings, and forging stock for high-temperature service.

• U.S. Military Standard:

  • MSRR 7250: Governs the procurement of Waspaloy raw materials.

• Unified Numbering System (UNS):

  • UNS N07001

For fastener products specifically, they are manufactured from material conforming to the above standards and are then produced to specific fastener standards, such as:

• NAS (National Aerospace Standard)

• MS (Military Standard)

• Customer-specific drawings and specifications that dictate dimensions, tolerances, and testing requirements.

3. Applications of Waspaloy Fastener Products

Due to their ability to maintain clamp load and not relax under extreme conditions, Waspaloy fasteners are critical in the most demanding applications:

• Aerospace & Jet Engines: This is the primary application. They are used extensively in the "hot sections" of gas turbine engines, including:

  • Turbine casings

  • Combustor assemblies

  • Afterburner components

  • Compressor sections (for high-temperature stages)

• Power Generation Turbines: Used in high-temperature bolting for industrial gas turbines in power plants.

• High-Performance Automotive: In turbochargers and exhaust systems for extreme-duty and racing applications.

• Chemical Processing Industries: For critical bolting in high-temperature reactors, valves, and piping systems where corrosion resistance is also required.

• Nuclear Reactors: In certain specialized components requiring high strength at temperature.