Nickel and Stainless Steel: The Right Combination for the Job
On its own, stainless steel is one of the most versatile metals. When nickel is combined with stainless steel , it takes on all new properties. These unique characteristics make nickel alloys the right choice for many jobs.
There are a number of different types of stainless steel and nickel alloys . Each kind differs in composition, corrosion resistance, physical properties and mechanical properties. The following checklist will help you decide the kind of nickel alloy that is best for your project:
- Corrosion Resistance
- Oxidation and Sulfide Resistance
- Strength and Ductility at Service and Ambient Temperatures
- Suitability for Intended Fabrication Techniques
- Suitability for Intended Cleaning Procedures
- Property Stability in Service
- Toughness
- Abrasion and Erosion Resistance
- Galling and Seizing Resistance
- Reflectivity
- Magnetic Properties
- Thermal Conductivity
- Thermal Expansion
- Electrical Resistivity
- Sharpness and Retention of Cutting Edge
- Rigidity
- Dimensional Stability
Though each of these characteristics are important, three stand out as deserving more attention and explanation: corrosion resistance, mechanical properties as well as cleaning requirements and fabrication .
One of the most important properties of nickel alloys
is corrosion resistance . While general corrosion to natural conditions is easy to measure, it is a less serious concern than localized corrosion. Stress corrosion cracking, crevice corrosion, pitting attacks and intergranular corrosion in sensitized materials (i.e. weld heat) are more important concerns. Localized corrosion can cause catastrophic failures and should always be carefully considered during the design process. The likelihood of a corrosive attack can be increased by impurities in the metals. This can be difficult to anticipate, especially when a small amount of impurities can cause serious problems. These attacks are more prevalent when the metal alloys are brought to high temperatures.
Mechanical properties mean the nickel and stainless steel alloys perform at service temperature as well as at other temperatures. This is one characteristic that is likely overlooked. For example, metal alloys in an arctic service product must perform at sub-zero temperatures and remain in a steady state at higher operating temperatures. Meanwhile, the product may be brought to room temperature, and the metals still need to perform well. This is especially important if the machinery is periodically shut down and brought to room temperature.
Fabrication and cleaning requirements are other oft overlooked properties . In many cases, nickel alloys are chosen for their variety of beautiful finishes. At this time, the selection of stainless steel sheets or stainless steel plates is made purely for appearance and ease of cleaning. Ease of cleaning is not as simple as some may think. It is advisable to test available finishes and make a selection based on finish, grade and durability. Most corrosion resistant finishes on nickel alloys will stay bright, even in a corrosive environment which would dull a lower quality allow steel.
Choosing the right metal alloys for your job is important to ensure success. Stainless steel and nickel alloys offer a wide variety of unique characteristics to support a multitude of needs. From corrosion resistance and mechanical properties to fabrication and cleaning requirements, nickel alloys can fulfill just about any metal need.
