Precision Alloy Wire — For Soft Magnetic, Expansion & Elastic
Components
ISO9001 & SGS Certified | Est. 2002 | 12,000 m² Factory | 0.5–7.5mm | 3–7 Day Dispatch
Precision alloy wire from Changzhou DLX Alloy Co., Ltd. covers
three essential functional material families — soft magnetic
alloys, expansion alloys, and elastic alloys — each engineered for
applications where conventional metals cannot deliver the required
physical properties. Whether you need ultra-high magnetic
permeability for sensitive transformer cores, precisely matched
thermal expansion for hermetic glass-to-metal seals, or exceptional
elastic stability for precision instrument springs, our 10-grade
precision alloy wire is manufactured through controlled melting,
multi-pass cold drawing, and optimized heat treatment to deliver
the magnetic, thermal, and mechanical properties your design
demands. Full EN 10204 3.1 MTC traceability on every spool.

| Family | Grade | Key Property | Best For |
|---|
| Soft Magnetic Alloys | 1J79 | Ultra-high initial permeability; very low coercivity | Precision transformer cores, magnetic shielding, sensitive relay
components, recording heads |
| 1J33 | High permeability; high saturation induction; good temperature
stability | Pulse transformers, magnetic amplifiers, current sensor cores,
solenoid components |
| 3J01 | High saturation induction; precipitation hardenable for structural
strength | Rotors in precision motors, magnetic pole pieces requiring
mechanical strength |
| Expansion Alloys | 4J29 (Kovar) | Thermal expansion matched to borosilicate glass | Glass-to-metal seals, transistor headers, hermetic microwave
packages, reed switch leads |
| 4J33 | Thermal expansion matched to alumina ceramics | Ceramic-to-metal seals, high-power vacuum tube feedthroughs,
semiconductor packaging |
| 4J45 | Thermal expansion matched to soft glass | Soft glass seals, incandescent lamp lead wires, CRT electron gun
components |
| Invar36 | Near-zero thermal expansion below Curie point (~230°C) | Precision measuring instruments, laser resonator frames, thermostat
bimetals, LNG tank membranes |
| 4J32 | Ultra-low expansion; good thermal conductivity | Precision length standards, microwave cavity resonators, optical
mounts requiring dimensional stability |
| FeNi50 | Moderate expansion; good glass wetting | Soft glass sealing applications requiring a lower-cost alternative
to higher-nickel grades |
| Elastic Alloy | 3J9 | High elastic limit; excellent fatigue resistance; low internal
friction | Precision elastic elements — diaphragms, bellows, tuning fork
resonators, pressure sensor capsules |
Not sure which grade? Tell us your required magnetic permeability, thermal expansion
coefficient, or elastic modulus target — our technical team
recommends the optimal grade and heat treatment within 24 hours.
Soft Magnetic Alloys — Magnetic Performance Guide
| Property | 1J79 (Permalloy-type) | 1J33 | 3J01 |
|---|
| Initial Permeability (μ₀) | ≥20,000 | High | Moderate |
| Maximum Permeability (μₘₐₓ) | ≥100,000 | ≥30,000 | Moderate |
| Coercivity (Hc) | ≤2.4 A/m | Low | Moderate |
| Saturation Induction (Bs) | ~0.75 T | ~1.3 T | ~1.2 T |
| Curie Temperature | ~450°C | ~500°C | ~500°C |
| Best Use Case | Maximum sensitivity — weak signal detection, precision transformers | High-power magnetic circuits — pulse transformers, inductors | Rotating magnetic components — motor rotors, resolver cores |
For maximum magnetic performance, soft magnetic alloy wire must be
annealed after forming in a controlled-atmosphere or vacuum
environment. Our technical team can provide recommended annealing
parameters for your specific component geometry.
Expansion Alloys — Thermal Expansion Guide
| Grade | Expansion Coefficient (*10⁻⁶/°C) | Temperature Range | Matched To |
|---|
| 4J29 (Kovar) | 4.6–5.2 (20–400°C) | −80 to 450°C | Borosilicate glass (Pyrex-type); alumina ceramics |
| 4J33 | 6.0–6.8 (20–400°C) | −60 to 500°C | High-alumina ceramics (95%+ Al₂O₃) |
| 4J45 | 7.8–8.8 (20–400°C) | −60 to 450°C | Soft soda-lime glass |
| Invar36 | ≤1.5 (20–100°C) | −200 to 230°C | Near-zero expansion applications; structural Invar for
dimensions-critical assemblies |
| 4J32 | ≤1.0 (20–100°C) | −60 to 200°C | Ultra-low expansion demands; optical and microwave components |
| FeNi50 | 9.2–10.0 (20–400°C) | −60 to 450°C | Soft glass; lower-cost alternative to 4J45 |

- 10 grades covering three functional families — Soft magnetic (1J79, 1J33, 3J01), expansion (4J29, 4J33, 4J45,
Invar36, 4J32, FeNi50), and elastic (3J9) alloys from a single
qualified supplier. No need to manage multiple vendors for
different functional materials in your bill of materials.
- Precision diameter: 0.5–7.5 mm — Multi-pass cold drawing with in-line diameter control.
Consistent cross-section for uniform magnetic, thermal, and
mechanical properties across every spool.
- Controlled melting for consistent functional properties — Tight chemistry control within each grade specification ensures
predictable magnetic permeability, thermal expansion coefficient,
or elastic modulus — batch to batch, heat to heat.
- Optimized heat treatment state for your process — Wire supplied in the condition best suited to your manufacturing
route. Soft magnetic grades annealed for immediate winding.
Expansion grades drawn to temper for seal fabrication. We match
delivery condition to your downstream process.
- Full traceability — heat to spool — Every spool linked to original heat number with EN 10204 3.1 MTC
showing full chemical composition. When your customer's hermetic
seal or magnetic circuit depends on alloy chemistry, the
documentation chain is complete.
- In-house production — melt to spool — Melting, forging, rolling, drawing, heat treatment, and testing
all under one roof. Consistent quality without variation from
outsourced processing steps.
Why Choose DLX Alloy?
Changzhou DLX Alloy Co., Ltd. was founded in 2002 with a single
focus: nickel-based specialty alloys. Our precision alloy wire
capability spans soft magnetic, expansion, and elastic alloy
families — materials where chemistry control and consistent
processing directly determine functional performance.
- 12,000 m² dedicated facility — integrated melting, forging, rolling, multi-pass drawing,
controlled-atmosphere heat treatment, and testing. Wire produced
under one roof from ingot to finished spool.
- 0.5–7.5 mm diameter range — from fine wire for sensitive magnetic components to heavy-gauge
wire for structural expansion alloy leads and seals.
- 1,200-ton annual capacity — automated drawing lines with in-line monitoring ensuring
consistent diameter and consistent functional properties across
every production run.
- Five product forms — bar, strip, tube, plate, and wire — integrated supply for
customers sourcing multiple material forms from a single qualified
vendor.
- ISO9001 quality management with multi-point traceability; SGS-accredited with BV and TV
third-party inspection available.
Source: DLX Alloy product catalog. EN 10204 3.1 MTC with full
composition included on every shipment.
| Item | 1J33 | 3J01 | 3J9 | 4J29 | 4J32 | 4J33 | 4J45 | FeNi50 | Invar36 | 1J79 |
|---|
| C | ≤0.05 | ≤0.05 | 0.22–0.26 | ≤0.03 | ≤0.05 | ≤0.05 | ≤0.05 | ≤0.05 | ≤0.1 | ≤0.03 |
| Mn | 0.30–0.6 | ≤1.0 | 1.80–2.20 | ≤0.5 | 0.2–0.6 | ≤0.5 | ≤0.8 | ≤0.8 | ≤0.5 | 0.6–1.1 |
| Fe | Bal. | Bal. | Bal. | Bal. | Bal. | Bal. | Bal. | Bal. | Bal. | Bal. |
| P | ≤0.020 | ≤0.020 | ≤0.03 | ≤0.02 | ≤0.02 | ≤0.02 | ≤0.02 | ≤0.02 | ≤0.006 | ≤0.02 |
| S | ≤0.020 | ≤0.020 | ≤0.020 | ≤0.02 | ≤0.02 | ≤0.02 | ≤0.02 | ≤0.02 | ≤0.04 | ≤0.02 |
| Si | 0.30–0.6 | ≤0.80 | 1.30–1.70 | ≤0.3 | ≤0.2 | ≤0.3 | ≤0.3 | ≤0.3 | ≤0.35 | 0.3–0.5 |
| Ni | 32.8–33.8 | 34.5–36.5 | 9.0–10.5 | 28.5–29.5 | 31.5–33.0 | 32.1–33.6 | 44.5–45.5 | 49.5–50.5 | 35–38 | 78.5–80.0 |
| Al | 1.0–2.0 | 1.0–1.8 | — | — | — | — | ≤0.1 | ≤0.1 | — | — |
| Co | — | — | — | 16.8–17.8 | 3.2–4.2 | 14.0–15.2 | — | — | — | — |
| Ti | — | 2.7–3.2 | — | — | — | — | — | — | — | — |
| Cu | — | — | — | ≤0.2 | 0.4–0.8 | — | — | — | — | ≤0.2 |
| Cr | — | 11.5–13.0 | 19.0–20.5 | ≤0.2 | — | — | — | — | — | — |
| Mo | — | — | 1.60–1.85 | ≤0.2 | — | — | — | — | — | 3.8–4.1 |

| Wire Diameter | 0.5–7.5 mm (per DLX Precision Alloy catalog Wire range) |
| Available Grades | 1J33, 3J01, 3J9, 4J29, 4J32, 4J33, 4J45, FeNi50, Invar36, 1J79 |
| Product Forms | Wire (0.5–7.5mm), Rod/Bar (8.0–200mm), Strip (0.5–2.5)*(5–180mm),
Tube & Plate (Custom) |
| Delivery Condition | Annealed, cold drawn (per grade and application requirement) |
| Surface Finish | Bright, oxide, coated (per customer requirement) |
| Packaging | Spooled on plastic or wooden reels; vacuum-sealed with desiccant |
| Testing | OES chemical analysis, diameter inspection, surface quality;
magnetic / expansion / mechanical testing per order |
Quality Assurance
| Stage | Test / Inspection | Standard |
|---|
| Melting | OES chemical analysis — tight targeting within grade specification | In-house / GB/T |
| Hot rolling / rod | Surface inspection, diameter check | In-house process spec |
| Cold drawing | In-line diameter monitoring at each pass, intermediate annealing
verification | ± tolerance per diameter |
| Post heat treatment | Functional property verification per grade: magnetic permeability
(soft magnetic), expansion coefficient (expansion), elastic modulus
(elastic) | Per grade specification |
| Final spool | Eddy current (if specified), visual inspection, dimensional audit,
spool tension check | Per order specification |
| Documentation | EN 10204 3.1 MTC, functional property test reports (if specified),
certificate of conformance | ISO9001 |
Third-party inspection by SGS, BV, or TV available upon request. All shipments fully documented and
traceable to heat number.
| Spool Types | Plastic reels (D55–D400) or wooden reels per customer specification |
| Packaging | Vacuum-sealed with desiccant, individually boxed; bulk orders on
wooden pallets |
| Spool Label | Grade, heat number, diameter, net weight, DLX traceability code |
| MOQ | Negotiable per grade and diameter; trial quantities supported for
first-time buyers |
| Lead Time | 3–7 days for stock items; 15–30 days for custom production orders |
| Shipping | Air freight (DHL, FedEx), sea freight (FCL/LCL), or
customer-designated forwarder |
| Payment | T/T, L/C at sight |
Frequently Asked Questions
What heat treatment do I need after forming soft magnetic alloy
wire?
Soft magnetic grades (1J79, 1J33, 3J01) require final hydrogen or
vacuum annealing after winding or forming to develop full magnetic
properties. Typical annealing: 1100–1200°C in dry hydrogen or
vacuum, slow cool. Our technical team can provide specific
parameters for your component geometry and target permeability.
Which expansion alloy do I need for a glass-to-metal seal?
4J29 (Kovar) for borosilicate hard glass (Pyrex-type). 4J45 or
FeNi50 for soft soda-lime glass. 4J33 for alumina ceramic seals.
The critical factor is matching thermal expansion curves through
the glass setting temperature range. Provide your glass or ceramic
type and we confirm the optimal grade.
Can you supply Invar36 with certified thermal expansion data?
Yes. Invar36 wire can be supplied with thermal expansion
coefficient measurement data over your specified temperature range.
Our standard certification includes EN 10204 3.1 MTC chemical
analysis; expansion coefficient certification is available on
request.
What is the minimum order quantity for trial evaluation?
Trial quantities are supported for all precision alloy grades and
diameters. We encourage first-time buyers to validate magnetic,
expansion, or elastic performance in their specific component
before committing to production volumes.
Can you supply wire for elastic elements — diaphragms and bellows?
Yes. 3J9 elastic alloy wire is available for precision elastic
components requiring high elastic limit, excellent fatigue
resistance, and low internal friction. Typical applications:
pressure sensor capsules, bellows, tuning fork resonators, and
precision instrument springs. Specify your required diameter and
delivery condition.
