The 4J33 Nickel-Iron Alloy Plate, also known internationally as Ni33Fe67, is a precision-engineered soft magnetic material with a low coefficient of thermal expansion (CTE) and excellent mechanical stability. Its properties make it a preferred choice for glass-to-metal sealing, vacuum tubes, sensor housings, and electronic packaging.
At DLX Alloy, we focus on producing high-quality 4J33 plates with consistent chemical composition, superior surface finish, and precise dimensional tolerances, ensuring reliability in applications where thermal expansion mismatch could lead to component failure.
4J33 is a nickel-iron alloy composed of approximately 33% nickel and 67% iron. Its combination of thermal stability, machinability, and strength makes it suitable for hermetic sealing applications where metal and glass must expand at nearly identical rates to avoid cracks or leaks.
Key material properties include:
Low coefficient of thermal expansion to match glass or ceramics
Excellent mechanical strength and ductility
Good corrosion resistance for long-term reliability
Stable electrical and magnetic properties under operational conditions
High processability, allowing precision cutting, forming, and welding
DLX Alloy utilizes vacuum induction melting, precise rolling, and controlled annealing to ensure uniform microstructure and minimize internal stress, producing 4J33 plates that maintain stability in demanding electronic and industrial applications.
Alloy Composition Table
Alloy Grades | C | S | P | Mn | Si | Ni | Cr | Co | Mo | Cu | Al | Nb | Fe | Other Elements |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
1J06 | 0.04 | 0.015 | 0.015 | ≤0.10 | ≤0.15 | - | - | - | - | - | 5.5-6.5 | - | Rest | - |
1J12 | 0.03 | 0.015 | 0.015 | ≤0.10 | ≤0.15 | - | - | - | - | - | 11.6-12.4 | - | Rest | - |
1J17 | 0.03 | 0.02 | 0.02 | ≤0.60 | ≤0.20 | - | 15.5-16.5 | - | - | - | - | - | Rest | - |
1J18 | 0.03 | 0.02 | 0.02 | 0.3-0.7 | ≤0.15 | 0.5-0.7 | 17-18.5 | - | - | - | - | - | Rest | Ti: 0.3-0.7 |
1J22 | 0.04 | 0.02 | 0.02 | ≤0.3 | ≤0.3 | ≤0.5 | - | 49-51 | - | ≤0.2 | - | - | Rest | V: 0.8-1.8 |
1J30 | 0.04 | 0.02 | 0.02 | ≤0.40 | ≤0.30 | 29.5-30.5 | - | - | - | - | - | - | Rest | - |
1J36 | 0.03 | 0.02 | 0.02 | ≤0.60 | ≤0.20 | 35.0-37.0 | - | - | - | - | - | - | Rest | - |
1J38 | 0.03 | 0.05 | 0.02 | 0.3-0.6 | 0.15-0.3 | 37.5-38.5 | 12.5-13.5 | - | - | - | - | - | Rest | - |
1J46 | 0.03 | 0.02 | 0.02 | 0.6-1.1 | 0.15-0.3 | 45.0-46.5 | - | - | - | ≤0.2 | - | - | Rest | - |
1J50 | 0.03 | 0.02 | 0.02 | 0.3-0.6 | 0.15-0.3 | 49-50.5 | - | - | - | ≤0.2 | - | - | Rest | - |
1J51 | 0.03 | 0.02 | 0.02 | 0.3-0.6 | 0.15-0.3 | 49-50.5 | - | - | - | ≤0.2 | - | - | Rest | - |
1J54 | 0.03 | 0.02 | 0.02 | 0.3-0.6 | 1.1-1.4 | 49.5-51 | 3.8-4.2 | - | - | ≤0.2 | - | - | Rest | - |
1J76 | 0.03 | 0.02 | 0.02 | 0.3-0.6 | 0.15-0.3 | 75.0-76.5 | 1.8-2.2 | - | - | 4.8-5.2 | - | - | Rest | - |
1J77 | 0.03 | 0.02 | 0.02 | 0.3-0.6 | 0.15-0.3 | 75.5-78 | - | - | 3.9-4.5 | 4.8-6.0 | - | - | Rest | - |
1J79 | 0.03 | 0.02 | 0.02 | 0.6-1.10 | 0.3-0.5 | 78.5-80.0 | - | - | 3.8-4.1 | ≤0.2 | - | - | Rest | - |
1J80 | 0.03 | 0.02 | 0.02 | 0.6-1.10 | 1.1-1.5 | 79.0-81.5 | 2.6-3.0 | - | - | ≤0.2 | - | - | Rest | - |
0.03 | 0.02 | 0.02 | 0.3-0.60 | 0.15-0.3 | 79.0-81.0 | - | - | 4.8-5.2 | ≤0.2 | - | - | Rest | - | |
1J87 | 0.03 | 0.02 | 0.02 | 0.3-0.6 | ≤0.3 | 78.5-80.5 | - | - | 1.6-2.2 | - | - | 6.5-7.5 | Rest | - |
For more details, pls directly contact us.
The 4J33 alloy plate is engineered for applications where thermal expansion matching is critical:
Glass-to-metal seals in vacuum tubes, light sources, and sensors
Electronic packaging requiring hermetic or semi-hermetic sealing
Sensor housings where dimensional precision under temperature variation is essential
Vacuum devices for aerospace or scientific instruments
Relays and switches in precision electronics
High-reliability assemblies in instrumentation and measurement devices
DLX Alloy customizes 4J33 plates in terms of thickness, dimensions, and surface finish, allowing engineers to integrate them seamlessly into temperature-sensitive assemblies.
Industry Trends
As the electronics, aerospace, and sensor industries advance, high-reliability sealing materials with matched CTEs are increasingly critical. Precision components require metals that expand at the same rate as glass or ceramics to maintain hermeticity and mechanical integrity.
Emerging trends influencing 4J33 demand include:
Miniaturization of electronic devices that amplifies the impact of thermal expansion mismatches
Aerospace and space exploration requiring vacuum-tight components that endure temperature fluctuations
Advanced semiconductor packaging demanding reliable hermetic enclosures
Medical and scientific instrumentation needing precise, stable, and corrosion-resistant materials
DLX Alloy meets these demands by producing 4J33 plates with tight chemical control, uniform microstructure, and dimensional precision, ensuring consistent performance for modern high-tech applications.
| Property / Alloy | 4J33 | 4J36 (Invar) | 4J29 (Kovar) | 4J42 |
|---|---|---|---|---|
| Nickel Content (%) | 33 | 36 | 29 | 42 |
| CTE (20–100°C, ×10⁻⁶/°C) | 3.0 | 1.2 | 5.0 | 2.0 |
| Density (g/cm³) | 8.0 | 8.1 | 8.2 | 8.1 |
| Yield Strength (MPa) | 220–320 | 250–350 | 250–350 | 300–400 |
| Thermal Stability | Good | Excellent | Moderate | Very Good |
| Corrosion Resistance | Good | Good | Moderate | Good |
| Typical Applications | Glass-to-metal seals, vacuum devices | Precision instruments, aerospace | Semiconductor packaging | Glass-to-metal seals, low-expansion frames |
| Processability | Good | Excellent | Moderate | Good |
The table highlights 4J33 as an ideal material for applications that need precise expansion matching without extreme performance requirements of Invar or Kovar alloys.
Why Choose DLX Alloy
DLX Alloy combines material science expertise with advanced production technology to deliver high-performance 4J33 plates.
Our advantages include:
Vacuum induction melting for chemical homogeneity and minimal impurities
Precision rolling and annealing for uniform thickness and stress reduction
Tight dimensional control for easy integration into assemblies
Custom surface finishes optimized for sealing or coating requirements
Comprehensive testing including CTE, mechanical, and chemical properties
These capabilities ensure 4J33 plates meet demanding specifications for glass-to-metal sealing, sensors, and precision electronics.
DLX Production and Quality Assurance
DLX Alloy leverages advanced production facilities and quality control protocols:
Vacuum induction furnaces to maintain alloy purity
High-precision rolling and annealing to optimize microstructure
Dimensional and surface inspections to ensure flatness and finish
CTE and mechanical property verification for each batch
We also offer customized dimensions, thicknesses, and surface treatments, allowing engineers to select the exact configuration for their application requirements.
The demand for 4J33 low- Expansion Alloy s continues to grow as industries require high-reliability, precision, and thermally stable materials.
DLX Alloy integrates sustainable manufacturing practices by minimizing waste, recycling excess material, and optimizing energy consumption during production. As precision electronics, aerospace sensors, and semiconductor packaging expand globally, DLX is positioned to supply reliable 4J33 plates for long-term use.
4J33 Nickel-Iron Alloy Plate is a critical material for glass-to-metal sealing, vacuum devices, and electronic packaging, offering low thermal expansion, mechanical stability, and corrosion resistance. Its combination of properties ensures reliable performance in temperature-sensitive, precision applications.
DLX Alloy guarantees high-quality 4J33 plates with consistent chemical composition, dimensional accuracy, and reliable thermal performance, supporting customers in aerospace, electronics, and instrumentation industries worldwide.
About Us:
Our 12,000㎡ factory is equipped with complete capabilities for research, production, testing, and packaging. We strictly adhere to ISO 9001 standards in our production processes, with an annual output of 1,200 tons. This ensures that we meet both quantity and quality demands. Furthermore, all products undergo rigorous simulated environment testing including high temperature, high pressure, and corrosion tests before being dispatched, ensuring they meet customer specifications.
For all our clients, we offer timely and multilingual after-sales support and technical consulting, helping you resolve any issues swiftly and efficiently.
Client Visits
Building Stronger Partnerships
We support all kinds of testing:
FAQs:
1. What is the composition of 4J33?
Approximately 33% nickel and 67% iron, optimized for thermal expansion matching with glass.
2. What is the main advantage of 4J33?
Its low CTE ensures dimensional stability for glass-to-metal sealing applications.
3. Which industries use 4J33 plates?
Aerospace, electronics, sensors, vacuum devices, and semiconductor packaging.
4. How does 4J33 compare with 4J36?
4J36 has lower thermal expansion, but 4J33 is more cost-effective and sufficient for many sealing applications.
5. Can DLX Alloy customize plate sizes and thickness?
Yes, we provide tailored dimensions and surface finishes for specific applications.
6. Is 4J33 suitable for glass and ceramic seals?
Yes, its expansion closely matches glass and ceramics to prevent stress or cracking.
7. What heat treatment improves 4J33?
Controlled annealing reduces internal stress and ensures dimensional stability.
8. Does DLX Alloy provide testing reports?
Yes, all batches come with CTE, mechanical, and chemical analysis documentation.
