1J50 Permalloy (Fe-50Ni Soft Magnetic Alloy) – Supplier of Strip, Bar & Plate | Shanghai Hangbo Alloy Group
Date: 2026年7月22日 Categories: News Views: 246
By Shanghai Hangbo Alloy Group Co., Ltd. | ISO 9001:2015 Certified | Est. 2012 | Shanghai, China
Contact: sales@hangboalloy.com | hangbo@nickel-alloy.com | WhatsApp: +86 13611656360
Quick Answer: What Is 1J50 Permalloy?
1J50 (Permalloy 50 / Fe-50Ni) is an iron-nickel soft magnetic alloy with approximately 50% nickel that delivers high saturation magnetic flux density (~1.55 Tesla), excellent maximum permeability (typically 50,000–100,000 μₘ), and low coercivity (≤14.4 A/m) after optimized hydrogen annealing. It is the most widely used Permalloy grade for magnetic shielding, instrument transformer cores, relay components, and electromagnetic pole pieces where a balance of high saturation capability and high permeability is required. Shanghai Hangbo Alloy Group supplies 1J50 in cold-rolled strip, round bar, and plate forms with hydrogen-annealed magnetic property certification per GB/T 14985.
Industry Pain Point: Magnetic component designers frequently default to grain-oriented silicon steel for cost reasons, then encounter permeability limits at low flux densities that degrade sensor accuracy. 1J50 Permalloy — at roughly 3–5× the cost of silicon steel but with 2–3× the permeability and 3–4× lower coercivity — eliminates the hysteresis error that causes instrument transformers to drift out of accuracy class within their first year of field service.
Key Properties at a Glance
| Property | Value |
|---|---|
| Grade Designation | 1J50 (GB) / Permalloy 50 / Fe-50Ni |
| International Equivalents | Carpenter 49 / Hy-Ra 49 / Permenorm 5000 H2 |
| Density | 8.20 g/cm³ (0.296 lb/in³) |
| Curie Temperature | ~480°C (~896°F) |
| Max Operating Temperature | ~450°C (limited by Curie point approach) |
| Saturation Flux Density Bs | ≥ 1.50 T (15,000 G) |
| Max Permeability μₘ (H₂ Annealed) | ≥ 31.3 mH/m (25,000) — standard; 50,000–100,000 typical optimal |
| Coercivity Hc | ≤ 14.4 A/m (0.18 Oe) |
| Electrical Resistivity | ~0.45 μΩ·m (45 μΩ·cm) |
| Key Standards | GB/T 14985, GB/T 15018, GB/T 32286.1 |
Product Overview
1J50 belongs to the 50% nickel class of Permalloys — the workhorse soft magnetic alloy family that bridges the gap between low-cost silicon steels (high saturation but modest permeability) and premium 79–80% nickel Supermalloy grades (extreme permeability but low saturation and high cost).
The 1J50 designation follows the Chinese precision alloy naming system where "1J" denotes a soft magnetic alloy and "50" indicates the nominal nickel content (49.0–51.0%). The international equivalents — Carpenter High Permeability 49, Vacuumschmelze Permenorm 5000 H2, Hy-Ra 49 — share the same fundamental Fe-50Ni metallurgy with minor compositional variations.
Three physical properties define the 1J50 value proposition:
- High Saturation Bs (~1.55 T): This is the key differentiator from the 79% Ni Permalloys (1J79: Bs ~0.75 T). 1J50 can carry approximately twice the magnetic flux before saturation, making it the correct choice for power-handling components (instrument transformer cores, relay armatures) where flux density — not ultimate permeability — is the design constraint.
- Moderate-High Permeability (μₘ 50,000–100,000): Decisively superior to silicon steels (μₘ ~20,000–40,000) and 2–3× that of low-carbon magnetic iron, enabling accurate low-level signal transformation with minimal excitation current.
- Low Coercivity (8–14 A/m): The narrow magnetic hysteresis loop means low core loss per magnetization cycle and rapid magnetic switching — critical for AC relay cores, pulse transformers, and magnetic modulators.
Critical process insight: 1J50 delivered from the mill in the cold-rolled condition has mediocre magnetic properties. The permeability values quoted here — and the performance the component designer relies on — are achieved only after a final hydrogen annealing process, typically performed by the end-user after stamping, machining, or winding. Shanghai Hangbo Alloy Group can supply 1J50 either as-rolled (for customer annealing after fabrication) or hydrogen-annealed with certified magnetic properties.
Executive Standards
| Product Form | Primary Standard | Supplementary Standards | Notes |
|---|---|---|---|
| Cold-Rolled Strip | GB/T 14985 | GB/T 15018 | Primary product form; thickness 0.05–2.5 mm, width up to 400 mm |
| Cold-Rolled Sheet | GB/T 14985 | GB/T 32286.1 | Thickness 0.5–4.0 mm |
| Hot-Rolled Bar | GB/T 14985 | GB/T 15018 | Diameter 6–100 mm typically |
| Hot-Rolled Plate | Custom specification | — | Thickness 5–50 mm; for large shielding structures |
| Cold-Drawn Wire | GB/T 14985 | — | Diameter 0.1–10 mm; for relay and solenoid cores |
| Forgings | Custom specification | — | Rings, discs, shaped pole pieces |
| International Ref. | ASTM A753 Alloy 4 equivalent | — | 50Ni-Fe magnetic alloy |
Chemical Composition (wt.% per GB/T 14985 – 100% OES Verified)
| Element | Min | Max | Role in 1J50 |
|---|---|---|---|
| Nickel (Ni) | 49.0 | 51.0 | Defines the alloy class — controls Curie temperature, saturation, and magnetocrystalline anisotropy. Peak permeability occurs at 48–50% Ni where magnetostriction (λ₁₀₀, λ₁₁₁) approaches zero. |
| Manganese (Mn) | 0.30 | 0.60 | Deoxidizer; stabilizes FCC γ-phase during annealing; improves hot workability |
| Silicon (Si) | 0.15 | 0.30 | Deoxidizer; increases electrical resistivity (reducing eddy current losses in AC applications) |
| Carbon (C) | — | 0.030 | Must be minimized — interstitial carbon pins magnetic domain walls, degrading permeability and increasing coercivity |
| Phosphorus (P) | — | 0.020 | Impurity; P at grain boundaries retards domain wall motion |
| Sulfur (S) | — | 0.020 | Impurity; forms MnS inclusions that pin domain walls; lower S = higher permeability |
| Iron (Fe) | Balance | — | Matrix element; provides the ferromagnetic BCC structure after annealing |
Metallurgical requirement: Unlike structural alloys where mechanical properties are the acceptance criterion, 1J50 purity is driven by magnetic performance. Every 0.01% of carbon above 0.02% typically reduces maximum permeability by 5,000–15,000 and increases coercivity by 2–4 A/m. The impurity tolerance is a magnetic specification, not a mechanical one.
Magnetic Properties (per GB/T 14985, after H₂ Annealing)
| Magnetic Parameter | Standard Requirement | Typical Optimal Value | Unit |
|---|---|---|---|
| Initial Permeability μᵢ | ≥ 2.5 mH/m | 3.0–5.0 mH/m | mH/m (≈ 2,000–4,000 in cgs) |
| Maximum Permeability μₘ | ≥ 31.3 mH/m | 50–120 mH/m | mH/m (≈ 40,000–100,000 in cgs) |
| Saturation Flux Density Bs (25°C) | ≥ 1.50 | 1.52–1.58 | T (15,000–15,800 G) |
| Remanence Br | — | 0.6–0.9 | T (dependent on annealing) |
| Coercivity Hc | ≤ 14.4 | 8.0–12.0 | A/m (0.10–0.15 Oe) |
| Hysteresis Loss Pₕ (B=1.0T, f=50Hz) | — | ~0.3–0.5 | W/kg |
Physical & Mechanical Properties
| Property | Value | Unit |
|---|---|---|
| Density | 8.20 | g/cm³ |
| Curie Temperature Tc | 480 ± 10 | °C |
| Electrical Resistivity (20°C) | 0.45 | μΩ·m (45 μΩ·cm) |
| Thermal Conductivity (20°C) | ~13 | W/m·K |
| Coefficient of Thermal Expansion (20–200°C) | 10.0 | μm/m·°C |
| Young's Modulus | ~165 | GPa |
| Tensile Strength (Annealed) | 450–550 | MPa |
| Yield Strength (Annealed) | 200–300 | MPa |
| Elongation (Annealed) | 30–40 | % |
| Hardness (Annealed) | 130–170 | HV |
Heat Treatment: Magnetic (Hydrogen) Annealing
This is the single most critical process for 1J50. The alloy's magnetic properties in the as-rolled or as-machined condition are poor — permeability below 5,000 μₘ, coercivity above 100 A/m. The hydrogen annealing step transforms these into the design values the component engineer relies on.
Standard H₂ Annealing Schedule
| Parameter | Specification |
|---|---|
| Temperature | 1050–1150°C (1920–2100°F) |
| Soak Time | 2–4 hours (longer times improve permeability by allowing grain growth; diminishing returns beyond 6 hours) |
| Heating Rate | ≤ 300°C/h to 600°C, then uncontrolled to anneal temperature (slow initial heating prevents thermal-distortion of thin strip laminations) |
| Atmosphere | Pure dry hydrogen, dew point ≤ −40°C (−40°F), flow rate sufficient for 2–3 furnace volume changes per hour. Vacuum annealing (≤10⁻³ Pa) is an acceptable alternative but produces marginally lower permeability than H₂. |
| Cooling Rate | Controlled slow cool: 100–200°C/h from anneal temperature down to 600°C, then faster furnace cool or inert-gas backfill to below 200°C before air exposure |
Why controlled slow cooling matters: The 100–200°C/h cooling rate through the 600–480°C window (around the Curie temperature) is the "magnetic ordering zone" where the ferromagnetic BCC domains form. Cooling too fast "freezes in" quenched-in stresses and a fine grain structure that pins domain walls, reducing permeability by 30–50%. Cooling too slowly offers no additional permeability benefit and wastes furnace time. The 100–200°C/h range is the empirically optimized compromise.
Atmosphere purity — the hidden failure mode: A dew point of −30°C (instead of ≤−40°C) introduces approximately 300 ppm H₂O partial pressure in the furnace. At 1100°C, this traces of water vapor selectively oxidizes silicon and manganese at the alloy surface, forming a sub-micron oxide layer that mechanically constrains near-surface magnetic domains — reducing permeability by 20–40% compared to a properly dry atmosphere. The furnace atmosphere is not a processing detail; it is a magnetic property specification.
Post-Fabrication Annealing (by the end-user)
Components stamped, machined, wound, or welded from 1J50 strip/wire must undergo a final magnetic anneal to remove cold-work-induced stresses that pin domain walls:
- Temperature: 1050–1150°C, hold 1–2 hours (smaller furnace loads need less time)
- Atmosphere: Pure dry H₂ or high vacuum
- Cooling: 100–200°C/h to 600°C, then furnace cool
- Do NOT exceed 1200°C — grain boundary melting of low-melting-point tramp elements can begin
Production Process
1. Cold-Rolled Strip (Primary Product Form)
- Melting: VIM (Vacuum Induction Melting) or VIM + ESR (Electroslag Remelting) for premium grades. The VIM process minimizes carbon pickup from electrode graphite and prevents silicon loss to slag — both critical for magnetic properties. Carbon target in the melt: ≤0.015% to provide margin below the 0.030% specification maximum.
- Hot Rolling: Ingot or ESR ingot heated to 1150–1200°C, hot-rolled to hot-band coil of 2.5–4.0 mm thickness. Finishing temperature ≥ 900°C to maintain FCC γ-phase formability.
- Cold Rolling: Multi-pass cold rolling with intermediate hydrogen anneals (1050–1150°C) between passes. Total cold reduction typically 50–90% depending on final gauge. Final cold reduction of 60–70% is standard — this level of cold work provides the stored energy that drives recrystallization and grain growth during the final magnetic anneal.
- Slitting & Finishing: Precision slitting to customer width (±0.05 mm tolerance for strip ≤ 0.5 mm thickness). Edge burr ≤ 0.01 mm — burrs create interlaminar shorts in stacked transformer cores. Vacuum-packed in moisture-barrier packaging with desiccant. Material shipped in "as-rolled" condition for customer final H₂ annealing after stamping/laminating.
2. Hot-Rolled Bar & Plate
- Melting & Forging: Same VIM/VIM+ESR melt route. Hot-forged or hot-rolled to bar from billet at 1100–1180°C, minimum 4:1 reduction ratio.
- Surface Conditioning: Peeled or ground to remove decarburized surface layer (the surface carbon depletion zone from hot working has different magnetic properties than the bulk and must be removed).
- H₂ Annealing (Optional): Mill can perform initial H₂ anneal (1050–1150°C, 2–4 h) to certify magnetic properties. Customer performs final anneal after machining.
- Inspection: Dimensional, visual, magnetic property test coupons from each heat-treatment lot. PMI on nickel content for grade verification.
3. Cold-Drawn Wire
- Wire Drawing: Hot-rolled rod annealed and cold-drawn through progressive dies to final diameter (0.1–10 mm). Intermediate H₂ anneals between drawing steps.
- Surface Finish: Bright drawn or pickled. For relay and solenoid core applications, surface must be free of drawing lubricant residue — residual carbon contamination degrades magnetic performance during customer H₂ anneal.
- Packaging: Spooled or coiled. Protective packaging against humidity (1J50 will rust in high-humidity storage — the 50% Fe content is susceptible to atmospheric corrosion unlike stainless grades).
Industry Applications
| Industry | Typical Component | Why 1J50? |
|---|---|---|
| Power & Instrumentation | Instrument transformer cores (CT/PT), current sensor cores | High permeability at low flux densities maintains accuracy class 0.2/0.5; low coercivity minimizes phase-angle error |
| Magnetic Shielding | MRI room shields, electron microscope enclosures, cryostat magnetic shields, EMI/RFI shielded rooms | High saturation (1.55T) handles Earth's field and stray fields without saturation; permeability 50,000+ attenuates 50/60 Hz fields by 40–60 dB in multi-layer shields |
| Relays & Solenoids | Relay armatures and cores, solenoid plungers, electromagnetic clutch disks | Low coercivity for fast magnetic switching; high saturation maximizes actuation force per unit core cross-section |
| Aerospace & Defense | Fluxgate magnetometer cores, magnetic modulators, gyroscope magnetic shields | Low magnetic noise floor (Barkhausen noise minimized by large grain size from optimized H₂ anneal) |
| Audio & Precision Electronics | Audio transformer cores, microphone transformers, moving-coil phono step-up transformers | Uniform permeability across the audio frequency band; low harmonic distortion from narrow hysteresis loop |
| Scientific Instruments | NMR pole pieces, mass spectrometer magnets, particle accelerator beam-line shielding | High saturation + moderate permeability + mechanical softness (machinable in annealed state for pole-tip contouring) |
Quality Assurance: 7-Stage Zero-Defect Inspection
- Raw Material Purity Verification: Incoming electrolytic nickel (≥ 99.95% Ni), pure iron, and silicon metal analyzed by ICP-MS. Carbon content of all charge materials verified ≤ 0.010% — the pre-melt carbon inventory is the primary predictor of final magnetic performance. Any charge material exceeding 0.015% C is rejected.
- VIM Melt Chemistry & Carbon Control: In-process sampling during VIM. Carbon verified by combustion analysis (ASTM E1019) to ≤ 0.015% (internal target, tighter than 0.030% spec). Nickel content verified ±0.3% of nominal 50.0%. Oxygen level monitored — O₂ > 30 ppm indicates vacuum leak and triggers abort.
- Hot-Band Decarburization Inspection: Hot-rolled coil edge samples examined metallographically for decarburization depth. A decarburized surface layer ≥ 50 μm requires surface grinding before cold rolling because the carbon-depleted zone has different magnetic saturation than the bulk, causing non-uniform flux distribution in finished cores.
- Cold-Rolled Strip Dimensional Verification: 100% in-line thickness gauging (X-ray or laser micrometer) during final cold rolling pass. Width and edge camber verified per GB/T 14985. Surface roughness Ra typically 0.2–0.6 μm.
- Hydrogen Anneal Process Control: Every furnace run logged: temperature (±5°C uniformity across work zone), dew point (≤−40°C continuously), H₂ flow rate, cooling rate through 600–400°C window. Furnace log archived with each lot's test certificate.
- Magnetic Property Testing (Per Heat-Treatment Lot): Ring samples or Epstein-frame samples per GB/T 3658 (soft magnetic materials measurement). DC initial magnetization curve, maximum permeability, coercivity, and remanence measured. AC core loss at 50 Hz / 1.0 T measured for instrument-transformer grade material. Any lot failing μₘ ≥ 31.3 mH/m minimum is re-annealed once; second failure triggers metallurgical root-cause analysis.
- Final Documentation & Shipment: GB/T 14985 test certificate with full chemistry, magnetic properties (μᵢ, μₘ, Hc, Bs), mechanical properties on request, dimensional conformance report, and H₂ anneal furnace chart. Third-party inspection available. Vacuum-packed in corrosion-protective packaging with desiccant.
Frequently Asked Questions
Q1: What is 1J50 Permalloy used for?
1J50 is used for magnetic cores and shields requiring high saturation flux density (~1.55 T) combined with high permeability (50,000–100,000). Primary applications: instrument transformer cores (current and voltage transformers for metering and protection), MRI and electron microscope magnetic shielding, relay and solenoid cores, fluxgate magnetometer sensors, audio transformer laminations, and electromagnetic pole pieces for scientific instruments. The 50% Ni composition places it in the "high field" Permalloy class — it is selected where a 79% Ni Permalloy (1J79) would saturate at the required operating flux density.
Q2: What is the density of 1J50?
8.20 g/cm³ (0.296 lb/in³) at 20°C — intermediate between pure iron (7.87 g/cm³) and pure nickel (8.90 g/cm³). Weight estimation for shielding design: Mass (kg) = 8.20 × Volume (cm³) ÷ 1000. A 1 m² × 1 mm thick 1J50 shield panel weighs 8.2 kg.
Q3: What is the maximum operating temperature of 1J50?
The Curie temperature is approximately 480°C, above which 1J50 becomes paramagnetic (non-magnetic). Practical maximum operating temperature is approximately 450°C — the magnetic permeability drops progressively as the Curie point is approached: μ drops ~20% at 300°C, ~50% at 400°C, and becomes effectively paramagnetic by 470°C. For applications requiring stable magnetic properties above 300°C, consider a cobalt-iron alloy (1J22 / Hiperco 50, Curie ~940°C) or a lower-nickel Permalloy (1J46, Curie ~430°C, but with different permeability characteristics).
Q4: What is the melting point of 1J50 Permalloy?
The melting range is approximately 1430–1450°C (2600–2640°F). The narrow ~20°C melting range reflects the binary Fe-50Ni composition with minimal impurities. Hydrogen annealing is performed well below this temperature — at 1050–1150°C — to avoid any risk of incipient melting.
Q5: What is the tensile strength of 1J50?
In the fully annealed condition (after H₂ magnetic anneal), tensile strength is typically 450–550 MPa (65–80 ksi). In the cold-rolled (as-supplied) condition, tensile strength is higher — approximately 650–800 MPa — but the material is work-hardened and has poor magnetic properties until the final customer H₂ anneal is performed. This is NOT a structural alloy; the mechanical properties are secondary to the magnetic performance.
Q6: What is the yield strength of 1J50?
In the annealed condition, 0.2% offset yield strength is typically 200–300 MPa (29–44 ksi). The alloy is intentionally soft after annealing — low yield strength correlates with low magnetostriction and minimal stress-induced magnetic anisotropy, both desirable for magnetic applications. Components stamped from annealed 1J50 strip must be handled carefully to avoid plastic deformation that would degrade permeability.
Q7: What is the saturation flux density (Bs) of 1J50?
Saturation magnetic flux density Bs is ≥ 1.50 T (15,000 G), with typical values of 1.52–1.58 T. This is the key reason to select 1J50 over 1J79 (79% Ni Permalloy, Bs ~0.75 T): 1J50 carries approximately twice the magnetic flux per unit core cross-section before saturation. Every millimeter of core cross-section operating near 1.5 T in 1J50 would require 2.0–2.1× the cross-section in 1J79 — directly translating to larger, heavier, more expensive cores.
Q8: What are the full magnetic properties of 1J50?
After optimized H₂ annealing (1050–1150°C, slow cool): initial permeability μᵢ ≥ 2.5 mH/m (typically 3–5 mH/m); maximum permeability μₘ ≥ 31.3 mH/m, typically 50–120 mH/m (40,000–100,000 in cgs units); coercivity Hc ≤ 14.4 A/m (0.18 Oe), typically 8–12 A/m; saturation Bs ≥ 1.50 T, typically 1.52–1.58 T. These values are achieved only after the final hydrogen anneal — material in the as-rolled condition has μₘ < 5,000 and Hc > 100 A/m. The magnetic properties are entirely process-dependent and are certified on annealed test coupons, not on the as-supplied condition.
Q9: What heat treatment does 1J50 require?
Hydrogen magnetic annealing at 1050–1150°C (1920–2100°F) for 2–4 hours, followed by controlled slow cooling at 100–200°C/h to 600°C, then faster cooling to ambient. The atmosphere must be pure dry hydrogen (dew point ≤ −40°C) or high vacuum (≤ 10⁻³ Pa). This is NOT a structural heat treatment — it is a magnetic property development process. The high temperature allows grain growth (larger grains = fewer domain-wall pinning sites = higher permeability), and the controlled slow cool through the Curie temperature (~480°C) allows stress-free magnetic domain ordering.
Q10: What is the hydrogen annealing temperature for 1J50?
1050–1150°C (1920–2100°F). The upper bound (1150°C) is limited by the risk of grain-boundary incipient melting from tramp elements. The lower bound (1050°C) is the minimum for adequate recrystallization and grain growth. Higher temperatures within this range (closer to 1150°C) produce larger grain sizes and higher maximum permeability; lower temperatures (closer to 1050°C) produce finer grains with higher mechanical strength at the cost of lower permeability. For maximum permeability applications (shielding, instrument transformers), anneal near the upper bound. For components subject to mechanical stress (relay armatures), anneal near the lower bound.
Q11: How does 1J50 compare to 1J79?
| Property | 1J50 (50% Ni) | 1J79 (79% Ni) | Selection Rule |
|---|---|---|---|
| Saturation Bs | ~1.55 T | ~0.75 T | 1J50 — 2× higher for power applications |
| Maximum Permeability μₘ | 50,000–100,000 | 150,000–300,000 | 1J79 — 2–3× higher for low-field sensitivity |
| Coercivity Hc | 8–12 A/m | 1–4 A/m | 1J79 — 2–4× lower hysteresis |
| Curie Temp. Tc | ~480°C | ~450°C | Similar |
| Electrical Resistivity | 0.45 μΩ·m | 0.55 μΩ·m | 1J79 — 20% higher, eddy currents lower |
| Density | 8.20 g/cm³ | 8.65 g/cm³ | 1J50 — ~5% lighter |
| Cost | Baseline | ~1.3–1.5× 1J50 | 1J50 — more economical for flux-handling applications |
Decision rule: If your core operates at flux densities above 0.7 T, or cost-per-unit-flux-capacity is a primary design constraint, select 1J50. If your application requires the highest possible sensitivity at low flux densities (magnetometers, sensitive current transformers, shielding where field levels are below 0.5 T), select 1J79.
Q12: What is the price of 1J50 Permalloy per kg?
Indicative EXW pricing for 1J50 cold-rolled strip (0.1–2.0 mm thickness) ranges approximately \$20–40/kg, with price strongly dependent on gauge, width, and order quantity. Narrow thin-gauge strip (<0.2 mm) commands the upper range due to higher cold-rolling reduction and process yield losses. Hot-rolled bar and plate are typically 15–25% lower in price. The dominant cost driver is electrolytic nickel (50% nickel content at ~\$18,000–25,000/tonne nickel means the raw nickel cost alone is ~\$9–13/kg of alloy). Shanghai Hangbo Alloy Group returns firm quotations within 2 business hours — email sales@hangboalloy.com with your strip dimensions, width, quantity, and magnetic property requirements (μₘ target, Hc target).
Q13: Is 1J50 Permalloy weldable?
Yes, but with an important caveat: welding destroys local magnetic properties. 1J50 can be welded by GTAW (TIG), resistance spot welding, or laser welding, but the weld zone and heat-affected zone (HAZ) undergo rapid solidification and cooling that leaves a fine-grained, stressed microstructure with permeability near zero and coercivity >500 A/m. A full re-hydrogen-anneal of the entire assembly is required to restore uniform magnetic properties.
For magnetic shielding assemblies, mechanical fastening (non-magnetic brass or austenitic stainless steel screws) or overlapping seam construction with hydrogen-annealed interlocking joints is preferred over welding — this preserves the pre-annealed magnetic properties and avoids the cost and dimensional distortion of a post-fabrication re-anneal.
Filler metal for essential welds: ERNi-1 (Nickel 61) or austenitic stainless filler (ER308L) — neither is magnetic and both provide adequate joint strength.
Q14: What product forms does Shanghai Hangbo supply for 1J50?
We supply 1J50 in cold-rolled strip (thickness 0.05–2.5 mm, width up to 400 mm — the dominant product form), cold-rolled sheet (0.5–4.0 mm), hot-rolled plate (5–50 mm, for magnetic shielding panels), hot-rolled round bar (Ø6–100 mm), cold-drawn wire (Ø0.1–10 mm, for relay and solenoid cores), and forgings (rings, shaped pole pieces). All products are supplied in the as-rolled/as-drawn condition for customer final magnetic anneal after fabrication. Hydrogen-annealed strip with certified magnetic properties is available for applications where the customer requires guaranteed pre-annealed performance (e.g., transformer core tape-wound toroids that receive no post-winding thermal treatment).
Q15: Does Shanghai Hangbo ship 1J50 internationally?
Yes. We export 1J50 Permalloy to over 40 countries with terms FOB Shanghai, CIF, CFR, and DAP. Standard destinations include USA, Germany, UK, Italy, Japan, South Korea, and India. Cold-rolled strip is the most common export product form — vacuum-packed in moisture-barrier packaging with desiccant to prevent atmospheric corrosion during ocean freight (the 50% Fe content is susceptible to rust). Stock items ship within 2–4 weeks; VIM mill-order production is 8–12 weeks for standard sizes. All export documentation: commercial invoice, packing list, certificate of origin, and GB/T 14985 or EN 10204 3.1 equivalent test certificate.
Q16: Why is hydrogen annealing critical for 1J50 — can't it be used as-supplied?
No. In the as-rolled or as-machined condition, 1J50 has undergone substantial cold work that creates a high density of crystal defects (dislocations, deformation bands, fine grain structure). These defects act as magnetic domain-wall pinning sites — every dislocation, grain boundary, and internal stress field arrests the motion of magnetic domain walls as the applied field is cycled. The practical consequence: as-rolled 1J50 has μₘ below 5,000 and Hc above 100 A/m — so magnetically poor that it would fail to function in any application requiring its specified properties.
Hydrogen annealing at 1050–1150°C recrystallizes the deformed microstructure into large, strain-free grains (typical final grain size ASTM 3–5, ~60–120 μm). The slow, controlled cool through the Curie temperature allows the ferromagnetic BCC domains to arrange in a low-energy configuration with minimal internal stress. The result is 10–20× higher permeability and 10× lower coercivity — transforming the alloy from a mediocre magnetic material into a high-performance soft magnet. The annealing is not optional; it is the process that defines 1J50 as a Permalloy.
Contact Shanghai Hangbo Alloy Group
| Channel | Details |
|---|---|
| Company | Shanghai Hangbo Alloy Group Co., Ltd. (宝昭实业（上海）有限公司) |
| Website | www.nickel-alloy.com |
| Email (Sales) | sales@hangboalloy.com |
| Email (Technical) | hangbo@nickel-alloy.com |
| +86 13611656360 | |
| Skype | live:specialalloy001 |
| Address | Room 1508, No. 288 Shiyi Road, Baoshan District, Shanghai 200940, China |
| ISO Certification | ISO 9001:2015 — View certificate on request |
| Response Time | ≤ 10 minutes during business hours (Mon–Fri, 08:00–18:00 GMT+8) |
Your Next Step
Email sales@hangboalloy.com with your 1J50 Permalloy specification:
- Product form: Cold-rolled strip / sheet / bar / wire / plate
- Dimensions: Thickness × width × length, or diameter × length (mm or inches)
- Condition: As-rolled (for customer annealing) or H₂-annealed with certified magnetic properties
- Magnetic requirements: μₘ target, Hc maximum, Bs minimum (if tighter than GB standard)
- Delivery destination: Full address + preferred incoterm (FOB / CIF / DAP)
For magnetic shielding design projects, our technical team can provide shielding attenuation estimates for multi-layer 1J50 enclosure geometries at no charge.
