Nickel Based Superalloys

Nickel based superalloys represent an elite class of materials exhibiting remarkable mechanical and corrosion resistance properties even at extreme temperatures. This comprehensive guide provides engineers, researchers, and technical buyers an in-depth reference covering all essential aspects of nickel based superalloys – ranging from metallurgy characteristics, processing methods, critical properties data, specifications, grades, and major applications.

Overview of Nickel Based Superalloys

Nickel based superalloys comprise a high percentage of nickel alloyed primarily with chromium, cobalt, molybdenum, tungsten, aluminum, titanium, iron, niobium, tantalum and other minor constituents. This tailored composition provides an exceptional combination of properties even at hot temperatures up to 85% of their melting point.

Key Characteristics:

  • Retain strength and toughness at high temps
  • Resist creep deformation
  • Withstand thermal fatigue
  • Excellent corrosion and oxidation resistance

Their capabilities empower performance in demanding industries including aerospace, oil and gas, automotive, chemical processing, and power generation where traditional materials fall short.

Composition of Nickel Based Superalloys

Alloying ElementRoleWeight %
NickelCorrosion resistance, ductility40-80%
ChromiumOxidation resistance10-25%
CobaltStrength at high temps0-15%
MolybdenumCreep strength0-6%
TungstenStability at high temps2-12%
AluminumOxidation resistance0-6%
TitaniumStrength, grain control0-5%
IronCost reduction0-20%

Balancing primary elements enables optimizing for key application requirements like tensile strength, creep life, oxidation resistance or cost targets.

Types of Nickel Based Superalloys

TypeDescription
Solid solution strengthenedPrimary alloying for high temp strength
Precipitation strengthenedSecondary alloying forms precipitates
ODS (Oxide dispersion strengthened)Nanoscale oxides for ultra-strength
Single crystalDirectional solidification, no grain boundaries

Advanced melting technologies allow creation of a widening range of nickel based superalloys for ever more extreme environments.

Nickel Based Superalloys

Manufacturing Processes

Producing nickel based superalloys is complex, requiring tightly controlled methods.

Primary Production Methods

ProcessDetails
Vacuum Induction Melting (VIM)Purity, composition control
Vacuum Arc Remelting (VAR)Minimizes defects, improves structure
Investment CastingComplex shapes
Wrought ProcessingDeformation mechanisms enhance strength
Powder MetallurgyHigh uniformity and performance
Direct Laser DepositionAdditive layering flexibility

Appropriate post processing like hot isostatic pressing (HIP), heat treatment, thermomechanical working and machining completes parts.

Form Availability

  • Cast ingots
  • Wrought billets
  • Powder for AM
  • Net shape castings
  • Plate, sheet, bar

Properties of Nickel Based Superalloys

PropertyTypical Value
Density8.0-9.2 g/cm3
Melting Point1250-1380°C
Young’s Modulus150-210 GPa
Yield Strength500-1300 MPa
Tensile Strength1000-1800 MPa
Elongation3-60%
Fatigue Strength100-800 MPa
Fracture Toughness20-250 MPa-m^1/2
Creep Strength100-800 MPa
Thermal Conductivity5-40 W/m-K
Thermal Expansion12-16 μm/m-K

Engineers select optimal nickel superalloy grades balancing properties like tensile strength, temperature rating, weldability, castability and cost for their operating environments.

Nickel Superalloy Specifications and Grades

Extensive superalloy classification systems have been developed to categorize thousands of complex chemistries available.

Alloy Categorization Systems

SystemBasis
UNS (Unified Numbering System)Composition based
AMS (SAE Aerospace Material Specs)Performance based
ProprietaryCompany branding

Widely Used Nickel Superalloy Grades

GradeDescription
Inconel 718Aircraft engines, withstand 650°C
Inconel 625Corrosion resistant, oxidizes slowly
Hastelloy XJet engine parts, resists 1090°C
Haynes 230Withstand extremes of heat flux
WaspaloyAerospace components, stable microstructure
René 41Aircraft engine cases, 1095°C rating

New proprietary alloys continually get developed, aiming to push performance boundaries further.

Machining Nickel Superalloys

Given excellent but complex metallurgical characteristics, machining nickel superalloys can prove uniquely challenging compared to conventional materials.

Following best practices is key:

  • Utilize rigid setups to minimize vibration
  • Employ sharper cutting tools for shearing
  • Use high pressure coolant directional spraying
  • Apply deflective tools path strategies
  • Optimize speeds, feeds and depths
  • Allow time for tools to cool

Thorough planning balancing tool life against quality and productivity prevents common pitfalls when working with these high performance alloys.

Applications of Nickel Superalloys

Aerospace and Aviation

  • Jet engine parts – combustor, turbine blades
  • Structural airframe components
  • Missile hardware
  • Instrumentation systems

Power Generation

  • Gas turbine hot section parts
  • Coal plant boiler components
  • Nuclear reactors
  • Waste incineration

Oil and Gas Industry

  • Downhole tools and drilling
  • Offshore platform equipment
  • Crack resistant piping
  • Corrosive process vessel parts

Nickel superalloys confer critical temperature, corrosion and wear resistance in the most unforgiving mechanical systems across industries.

Suppliers and Pricing

Obtaining raw forms or finished components requires connecting with highly specialized metalworking partners intimately familiar with nickel superalloys’ processing intricacies.

Leading Nickel Superalloy Manufacturers and Suppliers

CompanyLocation
AperamEurope
Allegheny TechnologiesUnited States
Carpenter TechnologiesUnited States
Haynes InternationalUnited States
High Performance AlloysUnited States
Special Metals CorporationUnited States

Nickel Superalloys Price Ranges

Product FormPrice Estimate Per Kilogram
Raw Material$25-60
Bar Stock$40-150
Plate/Sheet$50-250
Castings$80-600
Fasteners$80-1000

Cost multipliers stemming from specialized expertise required in manufacturing unique geometries and achieving critical quality standards account for their premium pricing.

Pros vs Cons

ProsCons
Retain high strength at extreme tempsRequires advanced alloy knowledge
Outstanding oxidation resistanceSensitive processing methods
Resist thermal fatigueChallenging/costly to machine
Withstand aggressive corrosionHigher material cost
Meet most demanding applicationsLimited weldability for some grades

For mission-critical components where failure proves catastrophic, nickel superalloys confer irreplaceable capabilities despite increased input requirements during production.

Nickel Based Superalloys

FAQs

Q: What is the difference between a superalloy and high performance alloy?

A: Superalloys exhibit exceptional properties at temperatures over 650°C. High performance alloys feature enhanced characteristics below this threshold. Both demonstrate capabilities exceeding standard stainless, tool or structural steels.

Q: Which nickel superalloy offers the best weldability?

A: Nickel alloy 625 provides the easiest welding for minimal dilution and cracking thanks to optimized chemistry and slow aging kinetics. Reduce heat inputs and allow generous post-weld stress relief for other grades.

Q: Can you 3D print nickel superalloys using metal AM?

A: Yes, selective laser melting and electron beam powder bed fusion now enable complex geometries once impossible through conventional methods alone. Repeatable quality still proves challenging.

Q: What is a nickel iron chromium superalloy?

A: This subset optimized as turbine blade materials balances high strength with imparting ductility – augmenting creep life through smart compositional adjustments lowering gamma prime formation rates.

Conclusion

From enabling efficient air travel to generating abundant clean power, nickel based superalloys represent the unsung hero material behind history’s greatest technological achievements. This guide sought as a foundational reference encapsulating everything technical professionals require when deciding if nickel superalloys prove the ideal selection. Please connect with an alloy expert for further insights answering your most pressing questions. The future beckons.

know more 3D printing processes

Share This Post:

Leave a Reply

Your email address will not be published. Required fields are marked *

Table of Contents

Most Popular

Get In Touch

Get in touch with us

On Key

Related Posts

TZM Powder

TZM Powder

TZM powder, or Titanium-Zirconium-Molybdenum powder, is a key material used in various industries for its outstanding properties like high temperature resistance, strength, and durability. But what exactly is TZM powder,

Read More »
C103 Powder

C103 Powder

If you’re looking for a unique metal powder with a range of industrial applications, you’ve probably come across C103 powder. This exotic metal alloy has properties that make it incredibly

Read More »
REP powders

Metal Powder for Welding

Welding is an intricate dance of heat, precision, and materials science. One key player in this dance is metal powder. If you’re diving into the world of metal powders for

Read More »
small_c_popup.png

Let's have a chat

Get In Touch With Us