NiCr 70/30 Nichrome Round Bar is a high-resistance alloy composed of approximately 70% nickel and 30% chromium. This well-balanced composition offers a unique combination of oxidation resistance, mechanical strength, and thermal stability. It’s one of the most durable heating materials in the industry, capable of performing reliably at elevated temperatures up to 1250°C. The alloy forms a protective oxide layer during heating, preventing scaling and ensuring a long operational lifespan in both industrial and laboratory applications.
Applications
Industrial and laboratory furnaces
Electric heating elements and resistance rods
Ceramic and glass manufacturing equipment
Aerospace engine components
Heat treatment furnaces and dryers
Chemical process heating systems
Electronic load resistors
Metallurgical heat exchangers
Industry Trends
In recent years, demand for high-temperature resistant alloys like NiCr 70/30 has surged due to the shift toward electric heating systems and cleaner industrial processes. Many sectors—especially metallurgy, aerospace, and electronics—are adopting NiCr-based materials to replace traditional carbon-based heating solutions.
At DZX, we’ve seen an increasing number of manufacturers looking for heating alloys that provide consistent performance and long-term reliability. Our NiCr 70/30 bars are produced with advanced melting, hot rolling, and precision machining technologies, ensuring uniform structure, high surface quality, and stable resistivity for demanding environments.
Alloy Nomenclature Performance | 1Cr13Al4 | 0Cr25Al5 | 0Cr21Al6 | 0Cr23Al5 | 0Cr21Al4 | 0Cr21Al6Nb | 0Cr27Al7Mo2 |
Chemical Compostion (%) | Cr | 12.0-15.0 | 23.0-26.0 | 19.0-22.0 | 20.5-23.5 | 18.0-21.0 | 21.0-23.0 | 26.5-27.8 |
Al | 4.0-6.0 | 4.5-6.5 | 5.0-7.0 | 4.2-5.3 | 3.0-4.2 | 5.0-7.0 | 6.0-7.0 |
Re | Opportune | Opportune | Opportune | Opportune | Opportune | Opportune | Opportune |
Fe | Rest | Rest | Rest | Rest | Rest | Rest | Rest |
| -- | -- | -- | -- | -- | -- | -- |
Max.Continuous service temp. of element |
950 |
1250 |
1250 |
1250 |
1100 |
1350 |
1400 |
Resistivity at 20C(μΩ.m) | 1.25 | 1.42 | 1.42 | 1.35 | 1.23 | 1.45 | 1.53 |
Density(g/cm) | 7.4 | 7.1 | 7.16 | 7.25 | 7.35 | 7.1 | 7.1 |
Thermal Conductivity(KJ/m.h) |
52.7 |
46.1 |
63.2 |
60.2 |
46.9 |
46.1 |
-- |
Coefficient of lines expansion(αx10-6/℃)
| 15.4 | 16 | 14.7 | 15 | 13.5 | 16 | 16 |
Melting Point Approx(degree) | 1450 | 1500 | 1500 | 1500 | 1500 | 1510 | 1520 |
Tensile Strength(N/mm) | 580-680 | 630-780 | 630-780 | 630-780 | 600-700 | 650-800 | 680-830 |
Elongation at rupture(%) | >16 | >12 | >12 | >12 | >12 | >12 | >10 |
Variation of area(%) | 65-75 | 60-75 | 65-75 | 65-75 | 65-75 | 65-75 | 65-75 |
Repeat Bending frequency(F/R) | >5 | >5 | >5 | >5 | >5 | >5 | >5 |
Hardness(H.B.) | 200-260 | 200-260 | 200-260 | 200-260 | 200-260 | 200-260 | 200-260 |
continuous service time(Hours/ ºC) | -- | ≥80/1300 | ≥80/1300 | ≥80/1300 | ≥80/1250 | ≥80/1350 | ≥80/1350 |
Micrographic structure | Ferrite | Ferrite | Ferrite | Ferrite | Ferrite | Ferrite | Ferrite |
Magnetic properties | Magnetic | Magnetic | Magnetic | Magnetic | Magnetic | Magnetic | Magnetic |
Shape | Size (mm) |
Wire | 0.05-7.5 |
Rod | 8-50 |
Ribbon | (0.05-0.35)*(0.5-6.0) |
Strip | (0.5-2.5)*(5-180)
|
For industries that operate at extreme temperatures, choosing the right heating alloy can determine both performance and efficiency. The NiCr 70/30 Nichrome Round Bar produced by DZX is one of the most trusted materials for electric heating and industrial furnace systems worldwide. Its unique balance of nickel and chromium offers exceptional oxidation resistance, strength, and stability.
At DZX, we manufacture NiCr 70/30 using a precision-controlled melting and rolling process that ensures consistency in every batch. This attention to detail means our customers receive bars with uniform resistivity and exceptional mechanical performance—qualities that are essential for high-end heating components.
Technical Comparison Table
| Parameter | NiCr 70/30 Nichrome Bar | FeCrAl Bar | CuNi Alloy Bar |
|---|
| Composition | Ni 70%, Cr 30% | Fe 72%, Cr 22%, Al 5% | Cu 80%, Ni 20% |
| Max Operating Temperature (°C) | 1250 | 1350 | 600 |
| Electrical Resistivity (μΩ·m) | 1.18 | 1.39 | 0.48 |
| Density (g/cm³) | 8.3 | 7.1 | 8.9 |
| Melting Point (°C) | 1395 | 1500 | 1280 |
| Oxidation Resistance | Excellent | Very Good | Moderate |
| Ductility | High | Medium | High |
| Magnetic Properties | Non-magnetic | Slightly magnetic | Non-magnetic |
| Mechanical Strength at 1000°C | Strong | Moderate | Weak |
The alloy’s 70/30 composition provides several performance benefits. Nickel contributes to toughness and resistance stability, while chromium strengthens the oxide layer that forms on the surface during operation. This protective layer acts as a natural shield, preventing scaling and degradation over long-term use. As a result, the material maintains a steady resistance value, ensuring accurate and consistent heating output across applications.
NiCr 70/30 is widely used in electric furnaces, laboratory heating systems, and industrial dryers. Many engineers also prefer it for use in glass and ceramics manufacturing, where temperature accuracy and uniform heat distribution are vital. Its excellent mechanical strength allows it to endure repeated thermal expansion and contraction cycles without cracking—a key factor in extending the lifespan of heating assemblies.
In comparison with FeCrAl, NiCr 70/30 offers slightly lower maximum temperature resistance but significantly higher ductility and strength at elevated temperatures. This makes it easier to form, weld, and integrate into complex heating designs. For applications that require high precision and minimal resistance drift, NiCr 70/30 remains the preferred choice.
At DZX, we’ve positioned ourselves at the forefront of heating alloy manufacturing by combining innovation with experience. Our production facility utilizes modern furnaces, vacuum melting systems, and precision testing equipment to guarantee material purity and consistency. Each batch undergoes chemical analysis, mechanical testing, and resistivity measurement before leaving our plant.
We also understand that every industrial application is unique. That’s why DZX offers complete customization—whether it’s diameter adjustments, surface polishing, or tailored resistance specifications. Our technical team works directly with customers to ensure the NiCr 70/30 bars fit perfectly into their systems, helping them achieve energy efficiency and performance goals.
As the global heating materials market continues to expand—driven by automation, renewable energy, and electric furnace innovation—NiCr 70/30 is becoming increasingly important. Its ability to deliver consistent performance under stress makes it indispensable for industries seeking longevity and stability in their heating elements.
What truly differentiates DZX is our dedication to reliability. Every NiCr 70/30 bar we produce reflects our commitment to quality control, metallurgical precision, and long-term partnerships with our clients. Our focus on continuous improvement ensures that our materials not only meet international standards like ASTM B267 and GOST but also exceed customer expectations in real-world applications.
In short, DZX NiCr 70/30 Nichrome Round Bar isn’t just a product—it’s a solution engineered for consistency, endurance, and efficiency. Whether it’s powering industrial furnaces, laboratory systems, or aerospace heating components, it delivers dependable performance where it matters most.
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
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We support all kinds of testing:
1. What makes NiCr 70/30 different from other Nichrome alloys?
NiCr 70/30 contains higher chromium content than NiCr 60/15 or 80/20, offering better oxidation resistance and stable performance under thermal cycling.
2. What’s the typical temperature range for NiCr 70/30 applications?
It operates efficiently up to 1250°C, making it suitable for high-temperature furnaces, air heaters, and resistance components.
3. How does DZX ensure consistent quality of NiCr 70/30 bars?
We use vacuum melting, precision hot rolling, and controlled heat treatment to maintain uniform chemical composition and mechanical stability.
4. Is NiCr 70/30 suitable for corrosive environments?
Yes. It forms a stable, self-healing oxide layer that protects the surface from oxidation and corrosion in air or controlled atmospheres.
5. Can it be machined or welded easily?
Absolutely. DZX NiCr 70/30 bars can be welded using TIG or resistance methods and machined to exact tolerances without cracking.
6. What industries commonly use this alloy?
NiCr 70/30 is used in metallurgy, energy, ceramics, aerospace, and chemical processing industries for heating elements and structural components.
7. What’s the lifespan of NiCr 70/30 under continuous operation?
With proper design and atmosphere control, it can last over 20,000 hours in continuous use without significant degradation.
8. How does DZX customize NiCr 70/30 bars?
We offer custom diameters, resistance ratings, and surface finishes to meet each customer’s technical and design requirements.
