Super-Invar is a precision low thermal expansion alloy supplied for applications where dimensional stability must be maintained under small temperature changes. It is commonly known as Super Invar 32-5, Alloy 32-5, UNS K93500, and in some markets may also be associated with precision alloy designations such as 4J32. Compared with standard Invar 36, Super-Invar is selected when even lower thermal expansion is required around room temperature. As a Super-Invar supplier, the key supply focus is not only alloy availability, but also chemical composition control, heat treatment condition, coefficient of thermal expansion performance, dimensional tolerance, surface finish, machining stability, certification, and reliable delivery. This article explains what Super-Invar material is, its chemical composition, low expansion properties, mechanical properties, product forms, standards, sizes, heat treatment, surface finishes, applications, quality inspection, stock availability, price factors, quotation tips, and how to choose a reliable Super-Invar supplier.
Super-Invar Supplier Overview
A professional Super-Invar supplier should understand that this material is usually purchased for precision engineering rather than ordinary metal fabrication. Buyers who request Super-Invar rod, Super-Invar sheet, Super-Invar plate, Super-Invar strip, or Super-Invar wire normally care about thermal expansion, dimensional stability, straightness, flatness, surface finish, stress relief, and material certification.
Unlike common steel or stainless steel, Super-Invar is not selected mainly for low price, high strength, or general corrosion resistance. It is selected because it offers extremely low coefficient of thermal expansion around ambient temperature. This makes it valuable for aerospace tooling, optical structures, laser systems, precision instruments, metrology equipment, scientific devices, satellite components, and high-accuracy mechanical assemblies.
What Buyers Usually Need from a Super-Invar Supplier
| Buyer Requirement | Supplier Responsibility | Why It Matters |
|---|---|---|
| Correct grade identification | Confirm Super Invar 32-5 / UNS K93500 / Alloy 32-5 | Prevents confusion with Invar 36, Kovar, Alloy 42, or other controlled expansion alloys. |
| Low thermal expansion performance | Provide suitable material condition and CTE data when required | Dimensional stability is the main reason to buy Super-Invar. |
| Precision size control | Support tight tolerance, straightness, flatness, and custom cutting | Precision assemblies often cannot accept ordinary mill tolerance. |
| Traceability | Provide MTC, heat number, chemical composition, and inspection records | Important for aerospace, optical, and scientific equipment projects. |
| Processing support | Offer cutting, grinding, machining blanks, stress relief, and surface finishing | Reduces machining risk and improves final part stability. |
What Is Super-Invar Material?
Super-Invar is an iron-nickel-cobalt controlled expansion alloy. The common grade name “Super Invar 32-5” refers to an alloy system with approximately 32% nickel and about 4% to 5% cobalt, with iron as the balance. The addition of cobalt helps reduce thermal expansion around room temperature compared with standard Invar 36.
Super-Invar is a magnetic, austenitic, solid-solution alloy. Its most important characteristic is extremely low thermal expansion near ambient temperature. In many precision applications, even a few microns of movement caused by temperature change can create alignment problems, measurement errors, optical drift, or assembly failure. Super-Invar helps reduce these risks.
Super-Invar vs Ordinary Steel
Super-Invar should not be compared with carbon steel only by strength and price. Ordinary steel expands much more when temperature changes. Super-Invar is more expensive because it contains nickel and cobalt and requires controlled production, heat treatment, and sometimes CTE verification. Its value comes from dimensional stability, not from being a general-purpose structural steel.
Super-Invar vs Invar 36
Invar 36 is a 36% nickel-iron alloy with low thermal expansion. Super-Invar 32-5 is used when lower expansion than Invar 36 is needed in a narrower temperature range around room temperature. Invar 36 is generally more common and more stable over broader use cases, while Super-Invar is selected for ultra-precision applications that justify tighter material control and higher cost.
Super-Invar Chemical Composition
The chemical composition of Super-Invar must be carefully controlled because thermal expansion performance is highly sensitive to alloy balance. Nickel and cobalt are the key alloying elements. Iron forms the balance. Minor elements such as carbon, manganese, silicon, sulfur, phosphorus, and chromium must be controlled to maintain material stability and processing quality.
Typical Super-Invar 32-5 Chemical Composition
| Element | Typical Range / Limit | Function in Super-Invar |
|---|---|---|
| Nickel (Ni) | About 31.50% – 33.00% | Main element for low thermal expansion behavior. |
| Cobalt (Co) | About 4.00% – 5.00% | Further reduces thermal expansion compared with standard Invar 36. |
| Iron (Fe) | Balance | Base matrix of the alloy. |
| Carbon (C) | Controlled low level | Excess carbon may affect stability and processing behavior. |
| Manganese (Mn) | Controlled minor element | Helps processing but must remain within specification. |
| Silicon (Si) | Controlled minor element | Controlled to maintain alloy cleanliness and stability. |
| Sulfur (S) | Low limit | Kept low to improve workability and reduce defects. |
| Phosphorus (P) | Low limit | Controlled impurity element. |
Why Composition Control Matters
For Super-Invar material, chemical composition is not just a basic grade confirmation item. It directly affects the coefficient of thermal expansion, stability after heat treatment, machining behavior, and final dimensional performance. A reliable supplier should provide a material test certificate showing the heat number and chemical composition. For precision applications, the buyer may also request CTE testing.
Key Properties of Super-Invar: Low Thermal Expansion
The key property of Super-Invar is extremely low thermal expansion near room temperature. This means the material expands and contracts much less than ordinary steel, stainless steel, aluminum, copper, brass, and many other engineering alloys when the temperature changes within its useful range.
Low Coefficient of Thermal Expansion
Super-Invar is especially valuable in the approximate -55°C to 95°C temperature range, where its thermal expansion can be lower than standard Invar 36. This makes it suitable for equipment that works in controlled room-temperature environments or moderate temperature variation ranges.
Dimensional Stability
Dimensional stability is the main reason engineers specify Super-Invar. In optical systems, satellite structures, measuring equipment, and precision instruments, small dimensional changes can cause misalignment. Super-Invar helps reduce thermal drift and improve long-term accuracy.
Important Limitations
Super-Invar does not maintain near-zero expansion at all temperatures. Its advantage is strongest around room temperature and within specific controlled ranges. At higher temperatures, expansion increases. For broader temperature ranges, Invar 36 or other controlled expansion alloys may sometimes be more practical. The working temperature range should always be reviewed before selecting Super-Invar.
| Property | Super-Invar Performance | Buyer Note |
|---|---|---|
| Thermal expansion | Extremely low near room temperature | Main reason for material selection. |
| Dimensional stability | Excellent in controlled temperature environments | Useful for optics, metrology, and aerospace tooling. |
| Magnetic behavior | Magnetic alloy | Important for instruments and electronic systems. |
| Machinability | Machinable with proper procedures | Stress relief may be needed for precision parts. |
| Corrosion resistance | Moderate, not a corrosion-resistant nickel alloy | Surface protection may be needed in corrosive environments. |
Mechanical Properties of Super-Invar
Super-Invar has moderate mechanical strength and good dimensional stability, but it is not normally selected as a high-strength alloy. Its mechanical properties depend on product form, cold work level, heat treatment condition, section size, and testing standard.
Typical Mechanical Property Considerations
| Property | General Performance | Procurement Note |
|---|---|---|
| Density | About 8.1 g/cm³ | Useful for weight calculation of rods, plates, and machined parts. |
| Tensile strength | Moderate, varies by condition | Cold worked material may show higher strength than annealed material. |
| Yield strength | Depends on heat treatment and cold work | Confirm if the part carries mechanical load. |
| Elongation | Good in annealed condition | Important for forming and machining behavior. |
| Hardness | Varies with delivery condition | Specify hardness requirement if needed. |
| Machining stability | Good when stress is properly controlled | Stress relief is often important for precision components. |
Mechanical Strength Is Not the Main Selection Reason
Buyers should not choose Super-Invar when the main requirement is maximum tensile strength, high-temperature creep strength, or severe corrosion resistance. If the project requires high strength and corrosion resistance, Inconel 718 or Inconel 625 may be more suitable. If the project requires glass-to-metal sealing, Kovar may be better. Super-Invar should be selected when ultra-low expansion is the controlling requirement.
Available Super-Invar Product Forms: Rod, Sheet, Plate, Strip, and Wire
Super-Invar can be supplied in several product forms depending on stock and production capability. Common forms include rod, round bar, sheet, plate, strip, wire, billet, block, and custom machined blanks. Among these, rod and plate are frequently requested for precision machined components and stable structural parts.
Common Super-Invar Product Forms
| Product Form | Common Supply Condition | Typical Use |
|---|---|---|
| Super-Invar Rod / Bar | Hot rolled, forged, cold drawn, annealed, ground | Precision shafts, supports, optical rods, measuring components. |
| Super-Invar Sheet | Cold rolled, annealed, cut sheet | Precision panels, covers, instrument components, formed parts. |
| Super-Invar Plate | Hot rolled, annealed, stress relieved, cut plate | Optical bases, tooling plates, mold components, machined blanks. |
| Super-Invar Strip | Cold rolled, slit, annealed, custom temper | Precision strips, instrument parts, small expansion-control parts. |
| Super-Invar Wire | Cold drawn, annealed, coil or straight wire | Precision wire parts, instrument components, small assemblies. |
| Custom Machined Blanks | Cut, ground, machined, stress relieved | Prototype parts, optical mounts, aerospace components, laboratory fixtures. |
Product Form Should Match Final Use
For optical mounts and measuring rods, precision ground rod may be suitable. For tooling bases and large stable structures, stress-relieved plate may be preferred. For small precision parts, strip or wire may be used. For complex components, custom machined blanks can reduce customer processing time, but machining allowance and stress control should be discussed before ordering.
Common Super-Invar Specifications and Standards
Super-Invar is often supplied according to ASTM F1684, UNS K93500, customer drawings, or supplier-specific technical requirements. Depending on product form and project, standards may define chemical composition, thermal expansion testing, heat treatment, mechanical properties, dimensional tolerance, and certification requirements.
Common Procurement References
| Reference | Meaning | Procurement Use |
|---|---|---|
| UNS K93500 | Unified Numbering System designation | Identifies Super Invar 32-5 material. |
| Super Invar 32-5 | Common commercial name | Used in supplier quotations and buyer inquiries. |
| Alloy 32-5 | Alternative commercial name | Refers to the iron-nickel-cobalt low expansion alloy system. |
| ASTM F1684 | Controlled expansion alloy standard reference | Often used for Invar and Super-Invar procurement. |
| Customer Drawing | Project-specific requirement | Controls final dimensions, tolerance, heat treatment, and inspection. |
| CTE Requirement | Coefficient of thermal expansion requirement | Important for precision and optical projects. |
Why Standard Confirmation Is Important
If a buyer only writes “Super-Invar material,” the supplier may quote commercial material without knowing the required CTE range, heat treatment, tolerance, or inspection level. For precision projects, the purchase order should clearly state UNS K93500, product form, size, condition, surface finish, CTE requirement if any, and certificate requirement.
Super-Invar Sizes, Tolerances, and Customization
Super-Invar sizes depend on product form and supplier stock. Rods may be supplied in small precision diameters or larger forged bars. Plates may be supplied in standard sizes or cut to drawing. Sheets and strips may be supplied in fixed widths, custom widths, or coil form. Because Super-Invar is more specialized than Invar 36, available stock may be more limited.
Common Size Information for Inquiry
| Product Form | Size Information Needed | Customization Options |
|---|---|---|
| Rod / Bar | Diameter, length, tolerance, straightness | Cut-to-length, ground surface, precision diameter, stress relief. |
| Plate | Thickness, width, length, flatness | Custom cutting, grinding, machining blank, stress-relieved plate. |
| Sheet | Thickness, width, length, surface | Custom cut sheet, polished surface, protective film. |
| Strip | Thickness, width, coil weight, edge condition | Slitting, deburring, custom temper, coil packing. |
| Wire | Diameter, coil size, temper, surface condition | Straightened wire, cut wire, annealed wire, precision drawn wire. |
| Machined Part | Drawing, tolerance, surface roughness, heat treatment | CNC machining, stress relief, inspection report, prototype supply. |
Tolerance Requirements
Tolerance is a major cost factor. Standard mill tolerance is more economical, but precision applications may need tight diameter tolerance, thickness tolerance, flatness, straightness, or surface roughness. Buyers should specify functional tolerances only where needed. Unnecessary tight tolerance can increase cost and lead time.
Heat Treatment and Delivery Conditions for Super-Invar
Heat treatment is very important for Super-Invar because thermal expansion behavior and dimensional stability depend strongly on processing condition. Depending on the application, Super-Invar may be supplied annealed, stress relieved, cold worked, hot rolled, forged, or custom heat treated.
Annealed Condition
Annealed Super-Invar is used when lower internal stress and better ductility are needed. It is often suitable for machining blanks, formed parts, and precision components that require stable behavior after processing.
Stress-Relieved Condition
Stress relief is often requested for precision rods, plates, optical components, aerospace tooling, and machined parts. If internal stress remains in the material, the part may distort during cutting, grinding, or final machining. Stress relief can improve machining stability and dimensional reliability.
CTE Heat Treatment
For applications where a specific coefficient of thermal expansion must be met, the supplier may need to follow a controlled heat treatment procedure. CTE performance should be discussed before production, because the heat treatment condition, sample size, testing method, and final product section can affect results.
| Condition | Main Purpose | Typical Application |
|---|---|---|
| Hot rolled | Economical stock for rough machining | Bar, plate, and general blanks. |
| Annealed | Improves ductility and reduces hardness | Machining blanks and formed parts. |
| Stress relieved | Reduces machining distortion and dimensional movement | Precision rods, plates, optical structures, tooling parts. |
| Cold drawn | Improves dimensional accuracy and surface quality | Small rods, wire, precision components. |
| Custom CTE condition | Targets specific low-expansion performance | Aerospace, metrology, optical, and scientific equipment. |
Surface Finishes and Processing Options
Surface finish and processing options are important for Super-Invar because many parts are used in precision assemblies. Surface defects, residual stress, poor straightness, or machining distortion can affect final performance.
Common Surface Finishes
| Surface Finish | Common Product Form | Use Case |
|---|---|---|
| Mill finish | Plate, sheet, bar | General machining stock and rough blanks. |
| Pickled / descaled | Sheet, plate, strip | Cleaner surface before fabrication or machining. |
| Peeled / turned | Rod and bar | Improves surface quality and removes outer defects. |
| Ground | Rod, bar, plate, machined blanks | Used for precision tolerance and smoother surface. |
| Polished | Sheet, strip, custom parts | Used where surface smoothness or appearance is important. |
| Machined | Blocks, plates, rods, custom parts | Used for near-finished or finished precision components. |
Processing Services
Common processing services include cutting, sawing, grinding, polishing, turning, milling, drilling, stress relief, custom machining, deburring, and inspection. For high-precision Super-Invar parts, rough machining plus intermediate stress relief may be useful before final machining.
Typical Applications of Super-Invar: Aerospace, Precision Instruments, and Optics
Super-Invar is used where extremely low thermal expansion is needed. Its strongest applications are usually in precision environments, not in heavy corrosion or high-strength structural service.
Aerospace Applications
In aerospace, Super-Invar may be used for precision fixtures, satellite components, optical supports, sensor housings, stable frames, and measuring equipment. Low expansion helps maintain geometry and alignment when the temperature changes during operation, testing, or storage.
Optical and Laser Systems
Optical systems require stable alignment. Super-Invar is used for lens supports, mirror mounts, laser system frames, optical benches, and precision mechanical supports. In these applications, surface finish, stress relief, flatness, and CTE control are often more important than raw material strength.
Precision Instruments and Metrology
Precision measuring devices, gauges, reference rods, laboratory instruments, and metrology systems may use Super-Invar to reduce measurement drift. For these uses, the supplier may need to provide CTE data, precision ground surfaces, and tight dimensional tolerance.
Molds and Tooling
Super-Invar can be used for molds, fixtures, and tooling parts where dimensional change must be minimized. However, for large aerospace composite tooling, Invar 36 may sometimes be more practical because of availability, cost, and broader tooling experience. Super-Invar is typically chosen when the expansion requirement is stricter.
| Industry | Typical Super-Invar Parts | Main Requirement |
|---|---|---|
| Aerospace | Satellite supports, precision fixtures, sensor parts, stable frames | Low expansion, traceability, dimensional stability. |
| Optics | Mirror mounts, lens frames, optical benches, laser supports | Alignment stability and low thermal drift. |
| Metrology | Reference rods, gauges, measuring frames, calibration parts | CTE control and precision tolerance. |
| Scientific Instruments | Laboratory fixtures, instrument bodies, precision supports | Stable dimensions under temperature variation. |
| Tooling | Low-expansion molds, fixture plates, machining blanks | Dimensional stability and stress control. |
Quality Inspection and Material Certification from Suppliers
Quality inspection is essential when buying Super-Invar because the material is usually used for precision applications. A reliable supplier should provide inspection documents that confirm grade, chemistry, size, condition, and traceability. When required, CTE testing should also be arranged.
Common Inspection Items
| Inspection Item | Purpose | When It Is Needed |
|---|---|---|
| Chemical composition test | Confirms Super-Invar / UNS K93500 chemistry | All professional Super-Invar orders. |
| Material Test Certificate | Shows grade, heat number, composition, size, and condition | Recommended for all industrial and export orders. |
| CTE test | Confirms coefficient of thermal expansion performance | Precision optics, aerospace, metrology, and scientific equipment. |
| PMI test | Prevents material mix-up | Useful before shipment and before machining. |
| Mechanical test | Checks tensile strength, yield strength, elongation, and hardness | Required when specified by standard or customer drawing. |
| Dimension inspection | Checks thickness, diameter, width, length, straightness, and flatness | Important for precision rods, plates, and sheets. |
| Surface inspection | Checks scratches, cracks, pits, scale, and machining defects | Important for ground, polished, and machined products. |
| Ultrasonic testing | Checks internal defects in thick sections | Useful for large rods, forged bars, and thick plates. |
| Third-party inspection | Provides independent verification | Used for critical export and high-value precision projects. |
Certificate and Traceability
The material certificate should match the delivered material. Heat number, grade, size, condition, and package marking should be traceable. For precision applications, buyers should confirm whether the CTE data is from the same heat, same condition, or representative test sample. This detail matters because expansion behavior can vary with heat treatment and processing condition.
Stock Availability, Lead Time, and MOQ Considerations
Super-Invar is more specialized than standard Invar 36, so stock availability may be limited. Common rods or plates may be available from some suppliers, but special sheet thicknesses, strip widths, wire diameters, precision ground rods, or large custom plates may require production.
Stock Material
Stock material is usually faster to deliver. If the stock size is close to the final dimension, the supplier can cut, grind, or machine it according to the buyer’s requirement. However, buyers should confirm whether the stock condition and CTE performance meet the project requirement.
Custom Production
Custom production may be needed for special dimensions, tight tolerances, unusual forms, specific heat treatment, or required CTE testing. Custom production usually has longer lead time and may require minimum order quantity.
Small Batch Supply
Small batch supply is important for prototypes, laboratory projects, optical assemblies, and repair work. Small quantities may be possible from stock, but the unit price can be higher because cutting, packing, testing, and documentation costs are spread over fewer kilograms.
| Supply Situation | Lead Time Impact | Cost Impact |
|---|---|---|
| Ready stock rod or plate | Shorter lead time after cutting and inspection | Usually more economical than new production. |
| Precision ground rod | Additional processing time | Higher due to grinding and tolerance control. |
| Custom sheet or strip | Longer lead time if rolling or slitting is needed | MOQ may apply. |
| CTE-tested material | Additional testing time | Higher because laboratory testing is required. |
| Prototype quantity | Fast if stock is available | Higher unit price due to handling and cutting cost. |
How to Choose a Reliable Super-Invar Supplier
Choosing a reliable Super-Invar supplier requires more than comparing price per kilogram. Buyers should check whether the supplier understands low expansion alloys, can confirm UNS K93500 material, can provide suitable heat treatment, and can support precision processing and certification.
Supplier Selection Checklist
| Supplier Checkpoint | What to Confirm | Why It Matters |
|---|---|---|
| Grade knowledge | Super Invar 32-5 / UNS K93500 / Alloy 32-5 | Prevents confusion with Invar 36, Kovar, or Alloy 42. |
| Material forms | Rod, bar, sheet, plate, strip, wire, machined blanks | Supports different project requirements. |
| Heat treatment support | Annealed, stress relieved, custom CTE condition | Important for dimensional stability and expansion behavior. |
| Precision processing | Cutting, grinding, polishing, machining, straightness control | Important for optical and metrology applications. |
| Testing capability | MTC, PMI, CTE test, mechanical test, UT, third-party inspection | Supports quality verification and project approval. |
| Traceability | Heat number, certificate, package marking, inspection records | Required for critical precision projects. |
| Export experience | Protective packing, documents, marking, international shipment | Reduces logistics and customs problems. |
Questions Buyers Should Ask
Before ordering, buyers should ask whether the supplier has stock, what heat treatment condition is available, whether CTE testing can be provided, what tolerance can be controlled, whether the material can be stress relieved after cutting or machining, and whether the certificate will show UNS K93500 material identity.
Super-Invar Price Factors and Quotation Tips
Super-Invar price is affected by nickel price, cobalt price, product form, size, tolerance, heat treatment, CTE testing, surface finish, quantity, stock status, and lead time. Because Super-Invar contains both nickel and cobalt and is more specialized than standard Invar 36, it is normally more expensive than Invar 36.
Main Price Factors
| Price Factor | How It Affects Cost | Buyer Suggestion |
|---|---|---|
| Nickel and cobalt cost | Raw material prices directly affect quotation. | Confirm quotation validity before ordering. |
| Product form | Rod, plate, sheet, strip, and wire have different processing costs. | Provide exact form in the inquiry. |
| Size and tolerance | Tight tolerance requires grinding, machining, or extra inspection. | Specify only functional tolerances. |
| Heat treatment | Stress relief or custom CTE heat treatment adds cost. | State dimensional stability requirements clearly. |
| CTE testing | Laboratory testing increases cost and lead time. | Request when the project needs certified expansion data. |
| Surface finish | Ground, polished, or machined surfaces cost more. | Choose surface according to final use. |
| Quantity | Small orders usually have higher unit price. | Use stock sizes or combine requirements when possible. |
| Lead time | Urgent orders may require stock sourcing or priority processing. | Check availability early for precision projects. |
How to Request a Quotation
To get an accurate Super-Invar quotation, buyers should provide grade, product form, size, tolerance, quantity, heat treatment condition, CTE requirement, surface finish, testing requirement, application, and delivery destination. A vague inquiry such as “Super-Invar price” is not enough for a reliable quotation.
| Inquiry Item | Example Information | Why It Matters |
|---|---|---|
| Grade | Super Invar 32-5 / UNS K93500 | Confirms the exact controlled expansion alloy. |
| Product form | Rod, bar, sheet, plate, strip, wire, machined blank | Determines stock availability and production route. |
| Size | Diameter, thickness, width, length, custom drawing | Affects quotation, cutting, machining, and packing. |
| Tolerance | Standard tolerance, h7, flatness, straightness, surface roughness | Precision tolerance increases processing cost. |
| Condition | Annealed, stress relieved, cold drawn, ground, custom heat treated | Affects CTE behavior and dimensional stability. |
| Testing | MTC, PMI, CTE test, mechanical test, UT, third-party inspection | Must be included before final quotation. |
| Application | Optical mount, aerospace fixture, measuring rod, scientific instrument | Helps supplier recommend proper condition and inspection. |
| Delivery destination | Country, port, courier address, trade term | Needed for packing, freight, and export documents. |
Example of a Clear Super-Invar Inquiry
A clear inquiry may read: “Please quote Super Invar 32-5 rod, UNS K93500, diameter 20 mm, length 1000 mm, precision ground surface, h7 tolerance, stress relieved condition, quantity 30 pieces, with MTC and CTE test report, used for optical support components, delivery to Germany.” This type of inquiry allows the supplier to check stock, confirm processing feasibility, calculate testing cost, and provide a more accurate lead time.
Super-Invar Packaging and Export Supply
Super-Invar is often used for precision parts, so packaging should protect the surface, dimensions, straightness, and traceability of the material. Poor packaging can cause scratches, bending, corrosion marks, or material mix-up during transportation.
Common Packaging Methods
| Product Form | Packaging Method | Protection Purpose |
|---|---|---|
| Rod / Bar | Bundles, plastic film, wooden cases, end protection | Prevents bending, scratches, and surface damage. |
| Plate / Sheet | Waterproof paper, wooden pallets, edge protection, separators | Protects flatness, edges, and surface condition. |
| Strip / Wire | Coil packing, moisture protection, inner core support | Prevents coil deformation and edge damage. |
| Ground or polished parts | Soft separation, protective film, custom wooden case | Protects precision surfaces and prevents scratches. |
| Machined blanks | Individual wrapping, labeled packaging, foam or separator protection | Protects dimensions and traceability. |
Export Documents
Typical export documents include commercial invoice, packing list, material test certificate, certificate of origin if required, third-party inspection report if requested, and shipping documents. For precision projects, package labels should show grade, heat number, size, quantity, net weight, gross weight, and customer order number.
Super-Invar Supplier Related Questions
What is Super-Invar used for?
Super-Invar is used for optical mounts, laser systems, aerospace fixtures, satellite components, precision instruments, measuring rods, metrology equipment, scientific devices, low-expansion frames, and high-accuracy mechanical assemblies. It is selected when extremely low thermal expansion and dimensional stability around room temperature are required.
What is the difference between Super-Invar and Invar 36?
Super-Invar 32-5 is an iron-nickel-cobalt alloy with about 32% nickel and about 4% to 5% cobalt, while Invar 36 is mainly an iron-nickel alloy with about 36% nickel. Super-Invar usually provides lower thermal expansion than Invar 36 around room temperature, but Invar 36 is more common, more widely available, and often more practical for broader applications.
How do I choose a Super-Invar supplier?
Choose a Super-Invar supplier by checking whether they can confirm UNS K93500 material identity, provide rod, sheet, plate, strip, or wire supply, support stress relief and precision processing, control tolerance and straightness, provide MTC and CTE testing when required, offer custom cutting or machining, and pack the material properly for export delivery.
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