ASTM B637 UNS N07718 parts are engineered from Inconel 718, a nickel-chromium alloy known for exceptional strength and corrosion resistance in extreme environments. These parts are designed for applications demanding high yield, tensile, and creep-rupture properties, especially in temperatures up to 1300°F. Their alloy composition, inclusive of nickel, chromium, and molybdenum, alongside heat treatment, enhances mechanical properties and increases resistance to fatigue and stress-corrosion cracking. Ideal for use in aircraft engines, gas turbines, and other critical high-temperature applications, these parts offer a balance of durability and performance. Exploring further will reveal insights into their manufacturing processes, quality control, and versatile applications across industries.

Introduction

Inconel 718, designated as ASTM B637 UNS N07718, stands as a critical material in the engineering and manufacturing sectors due to its remarkable alloy composition and mechanical properties. This nickel-chromium alloy is renowned for its high yield, tensile, and creep-rupture properties at temperatures up to 1300°F. The alloy composition of Inconel 718 includes significant amounts of nickel, chromium, and molybdenum, contributing to its outstanding strength and corrosion resistance.

Heat treatment of Inconel 718 enhances its mechanical properties, making it suitable for demanding applications. The standard heat treatment process involves solution annealing and aging, which precipitates the secondary phases that harden the alloy. This treatment improves the material’s fatigue strength and stress-corrosion cracking resistance, essential for its performance in harsh environments.

Furthermore, Inconel 718 exhibits excellent weldability. Welding techniques, including gas-tungsten arc welding, shielded metal arc welding, and electron beam welding, are effectively applied without adversely affecting its corrosion resistance. This weldability, combined with its mechanical properties and corrosion resistance, makes ASTM B637 UNS N07718 a preferred choice for complex engineering applications, including aircraft engines and gas turbine parts.

Chemical Composition

ASTM B637 covers precipitation hardening and cold worked nickel alloy bars, forgings, and forging stock for moderate or high-temperature service. The UNS N07718 (commonly known as Inconel 718) is a high-strength, corrosion-resistant nickel-chromium material used at -423° to 1300°F.

The chemical composition of Inconel 718 (UNS N07718) according to ASTM B637 is as follows:

• Nickel (Ni):00 – 55.00%
• Chromium (Cr):00 – 21.00%
• Iron (Fe):Balance
• Molybdenum (Mo):80 – 3.30%
• Niobium (Nb) + Tantalum (Ta):75 – 5.50%
• Titanium (Ti):65 – 1.15%
• Aluminum (Al):20 – 0.80%
• Cobalt (Co):00% max
• Copper (Cu):30% max
• Manganese (Mn):35% max
• Silicon (Si):35% max
• Phosphorus (P):015% max
• Sulfur (S):015% max
• Boron (B):006% max
• Carbon (C):08% max

Please note that these are the maximum or range values for each element in the alloy composition. The balance is iron, but it is important to note that nickel is the predominant element after chromium.

Inconel 718 is known for its high yield, tensile, and creep-rupture properties at high temperatures and is used in applications such as gas turbines, rocket motors, spacecraft, nuclear reactors, pumps, and tooling.

Parts and Application

ASTM B637 specification for UNS N07718 (commonly known as Inconel 718) covers nickel alloy bars, rods, forgings, and forging stock, particularly those that are precipitation hardening and are intended for use in high-temperature applications. Parts and components made from materials that meet ASTM B637 N07718 specifications include, but are not limited to:

Aerospace Components: Turbine blades, turbine discs, casings, engine parts, and various components in due to the alloy’s resistance to high-temperature corrosion and its strength at elevated temperatures.

Gas Turbine Parts: Components that require high strength and corrosion resistance to 700°C (1290°F), such as bolts, fasteners, and casing parts.

Oil and Gas Industry: High-strength, corrosion-resistant parts for downhole and surface gas well components, such as valves, fasteners, tool joints, and instrumentation parts.

Nuclear Reactors: Control rods, pump parts, and nuclear fuel element spacers, where the material’s resistance to radiation damage is beneficial.

Power Generation: Hot sections of gas turbines, such as blades and vanes, which require materials that can withstand high temperatures and corrosive environments.

Components that need to retain high strength at cryogenic temperatures.

Chemical Processing Equipment: Parts that require high yield, tensile, and creep-rupture properties, as well as good ductility up to moderately high temperatures.

Fasteners: High-strength bolts and screws, which can be used in a variety of industries.

Pump Shafts and Rings: Parts that need wear resistance along with high strength and corrosion resistance.

Pressure Vessels: Components for reactors and storage tanks that operate under high pressure and temperature conditions.

It’s important to note that while ASTM B637 covers the specifications for the material itself, the actual design and engineering of parts will depend on the specific requirements of the application, including the expected stresses, temperatures, and corrosive environments the parts will encounter. The standard ensures that any material produced to N07718 chemical properties for its intended use.

Design Considerations

For engineers seeking materials that excel in high-temperature and corrosive environments, ASTM B637 UNS N07718 parts present an essential choice. These components are engineered to withstand extreme conditions, making them suitable for applications requiring durability and reliability. However, design considerations are paramount when incorporating these materials into projects. Compatibility with other materials necessitates a thorough analysis to prevent galvanic corrosion and ensure structural integrity. Stress and load considerations are vital; understanding the mechanical properties under operational conditions will guide the design process to avoid failure. Additionally, dimensional tolerances must be meticulously planned. Precise tolerances ensure that parts fit correctly and function as intended, minimizing the risk of malfunctions or breakdowns. Collectively, these considerations guarantee the successful implementation of ASTM B637 UNS N07718 parts in demanding applications.

Best For: Engineers and designers in industries such as aerospace, oil and gas, and chemical processing who require materials that can withstand high temperatures and corrosive environments.

Manufacturing Process

Understanding the design considerations of ASTM B637 UNS N07718 parts lays the foundation for exploring the intricate manufacturing process required to produce these high-performance components. The initial step involves forging and shaping, where precise forging techniques create the primary form of the parts. This process is vital for establishing the material’s microstructure, which greatly influences its final properties.

Following forging, the parts undergo heat treatment processes, specifically precipitation hardening, to enhance their mechanical properties. This step is essential for achieving the desired strength and durability, making the material suitable for extreme environments.

Machining and finishing are next, utilizing advanced machining methods to achieve the precise dimensions and surface finishes required for specific applications. This stage ensures that each part meets the stringent specifications outlined in ASTM B637.

Joining procedures, including welding and brazing, are employed to assemble the components as needed. These techniques must be carefully selected and applied to maintain the integrity of the material’s properties.

Lastly, surface treatments such as coatings and plating are applied to further enhance the parts’ resistance to corrosion and wear. Each of these manufacturing steps, from forging techniques to surface treatments, contributes to the overall performance and reliability of ASTM B637 UNS N07718 parts.

Quality Control and Testing

Guaranteeing the reliability and performance of ASTM B637 UNS N07718 parts necessitates a thorough approach to quality control and testing. This involves a complete blend of non-destructive testing (NDT) techniques and destructive methods to ascertain the material integrity and mechanical properties of the parts. NDT techniques offer the advantage of evaluating the components without causing damage, making them essential for ongoing quality assurance and reliability assessments.

Quality assurance processes are rigorous, incorporating both dimensional inspections and material analysis to ensure that each part meets strict specifications for dimensional accuracy and material composition. These inspections are critical in verifying that the parts conform to the required standards, ensuring their reliability in various applications.

Certification and traceability form another cornerstone of the quality control process. Each ASTM B637 UNS N07718 part is accompanied by certification that verifies its compliance with testing protocols and material specifications. This traceability ensures that each component can be traced back to its manufacturing batch, providing a clear lineage that supports quality assurance efforts.

Together, these measures—ranging from NDT techniques and destructive methods to detailed inspections and certification—form a robust framework designed to guarantee the highest levels of quality and reliability in ASTM B637 UNS N07718 parts.

Custom ASTM B637 UNS N07718 Parts

Able Hardware specializes in the customization of ASTM B637 UNS N07718 parts, catering to specific industry needs with precision engineering and design. Their technical expertise and innovative approach allow for the development of high-performance components that meet the rigorous demands of various sectors, including aerospace, oil and gas, and power generation. Key considerations in their customization process include:

• Pricing strategies: Able Hardware employs competitive pricing models, ensuring that clients receive value without compromising on quality. This approach is important in industries where cost-efficiency is as essential as performance.
• Supplier selection: The choice of raw material suppliers is strict, emphasizing quality, reliability, and sustainability. This ensures that the final product not only meets but exceeds industry standards.
• Lead times: Understanding the importance of project timelines, Able Hardware optimizes production processes to minimize lead times, enabling faster market entry for their clients.
• Environmental impact: Sustainability is at the core of their operations, with measures in place to reduce the environmental footprint of their manufacturing processes.
• Export regulations: Managing the complex landscape of international trade, Able Hardware ensures compliance with all relevant export regulations, facilitating hassle-free delivery of parts globally.

Through meticulous attention to these factors, Able Hardware stands as a leader in custom ASTM B637 UNS N07718 parts manufacturing.