Steel 45 Permalloy MagAnn
Heat-treated state
MagAnn = magnetic (final) anneal
Choose for finished cores/shields: gives maximum permeability and lowest coercivity, but parts become soft and stress-sensitive and cannot be reworked.
Values for the MagAnn condition
Other 45 Permalloy tempers and conditions
45 Permalloy is listed in 7 conditions; see the grade overview at 45 Permalloy.
Compare all 7 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
MagAnnThis page Magnetic (final) anneal | Choose for finished cores/shields: gives maximum permeability and lowest coercivity, but parts become soft and stress-sensitive and cannot be reworked. | 170 | 470 | 45 | 105 HB | 3.8 % IACS |
annealed and cooled in a longitudinal/transverse field (loop shaping) | Pick when a squared (Z-type) or flattened (F-type) B-H loop is needed, e.g. magnetic amplifiers, saturable reactors and pulse cores. | 170 | 470 | 45 | 105 HB | 3.8 % IACS |
ANNDefault Annealed | Standard stocked soft condition: formable and machinable, magnetic properties still to be developed by the customer's final anneal. | 210 | 520 | 40 | 125 HB | 3.8 % IACS |
Hot rolled | Semi-finished heavy sections for further machining; scale must be removed and a full magnetic anneal applied afterwards. | 250 | 540 | 35 | 135 HB | 3.8 % IACS |
Half hard | Compromise temper for parts that need some stiffness/handling strength yet still bend without cracking. | 560 | 720 | 10 | 17 HRC | 3.8 % IACS |
Cold drawn | Use for machined cores, pole pieces and relay armatures where straightness, tolerance and strength are wanted before the final anneal. | 600 | 760 | 15 | 20 HRC | 3.8 % IACS |
Cold rolled | Supplied hard for springy stampings, shims and for customers who stamp then anneal the finished part. | 800 | 950 | 3 | 28 HRC | 3.7 % IACS |
What is 45 Permalloy MagAnn?
45 Permalloy MagAnn is 45 Permalloy heat treated to MagAnn — choose for finished cores/shields: gives maximum permeability and lowest coercivity, but parts become soft and stress-sensitive and cannot be reworked. 45 Permalloy MagAnn has a yield strength of 170 MPa (24.7 ksi) and a tensile strength of 470 MPa (68.2 ksi) — weaker than 99% of steel grades. Elongation at break is 45% and the elastic modulus is 148 GPa (21.5 Msi). 45 Permalloy MagAnn has a density of 8.17 g/cm³ (0.295 lb/in³), heavier than 98% of steel grades. It melts at 1,425°C (2,597 °F). ANN is the default condition FabDigit quotes; MagAnn is available on request or by drawing note.
Advantages
- Ductile — tolerates forming and impact — 45%, better than 100% of steel grades
- Good corrosion resistance — 32/100, better than 96% of steel grades
- Polishes to a fine finish — 70/100, better than 87% of steel grades
- Forms and bends easily — 70/100, better than 86% of steel grades
Limitations
- Low strength — 170 MPa (24.7 ksi), worse than 99% of steel grades
- Poor heat conductor — 13.5 W/m·K (7.8 BTU/hr·ft·°F), worse than 99% of steel grades
- High embodied carbon — 7.5 kg CO₂/kg, worse than 99% of steel grades
- Low stiffness — 148 GPa (21.5 Msi), worse than 98% of steel grades
- Difficult to machine — 30/100, worse than 89% of steel grades
45 Permalloy MagAnn properties
Typical room-temperature values for 45 Permalloy MagAnn; 21 are specific to this condition. Other listed values are 45 Permalloy reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
45 Permalloy MagAnn has a density of 8.17 g/cm³ (0.295 lb/in³), heavier than 98% of steel grades. It melts at 1,425°C (2,597 °F).
Mechanical14
45 Permalloy MagAnn has a yield strength of 170 MPa (24.7 ksi) and a tensile strength of 470 MPa (68.2 ksi) — weaker than 99% of steel grades. Elongation at break is 45% and the elastic modulus is 148 GPa (21.5 Msi).
Thermal6
45 Permalloy MagAnn is rated for continuous service to 400°C (752 °F). It conducts heat at 13.5 W/m·K (7.8 BTU/hr·ft·°F), worse than 99% of steel grades. Thermal expansion is 8.5 µm/m·K (4.72 µin/in·°F).
Electrical3
45 Permalloy MagAnn conducts electricity at 3.8 % IACS, worse than 84% of steel grades.
Chemical & Environmental3
Corrosion resistance is poor (32/100), better than 96% of steel grades.
Sustainability4
Producing a kilogram of 45 Permalloy MagAnn takes about 90 MJ of energy and emits 7.5 kg of CO₂ — more than 98% of steel grades. Typical recycled content is 20%.
Manufacturability7
45 Permalloy MagAnn's machinability is poor (30/100, worse than 89% of steel grades); weldability good (60/100); formability very good (70/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 45 Permalloy MagAnn
Is 45 Permalloy easy to machine?
Gummy and work-hardening — use sharp positive-rake carbide, heavy feed, low-to-moderate speed and flood coolant; leave a finish anneal after machining to restore magnetics.
Can 45 Permalloy be welded?
TIG, laser and resistance welding are fine with matching Ni-Fe filler and low heat input, but the weld and HAZ lose permeability until the assembly is re-annealed in hydrogen.
Can 45 Permalloy be formed, bent or molded?
Annealed strip stamps, deep-draws and bends readily; avoid residual stress and never straighten a finished core, then hydrogen anneal parts on flat ceramic supports.
What surface finishes work on 45 Permalloy?
No anodising; protect with nickel or tin plating, chromate-free lacquer or an epoxy-coated shielding can, and handle annealed shields gently to preserve magnetic performance.
45 Permalloy chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| Ni45-type; the 1J50 / Alloy 48–50 sub-grades run 47–51 % Ni for higher Bs | 45 – 46.5 | 45.5 |
| Mndeoxidiser/sulphur control | 0.3 – 0.6 | 0.45 |
| Si | 0.15 – 0.3 | 0.2 |
| Ckept low for magnetic softness | ≤ 0.03 | 0.02 |
| S | ≤ 0.02 | 0.01 |
| P | ≤ 0.02 | 0.01 |
| Cu | ≤ 0.2 | 0.05 |
| Febalance, vacuum induction melted | balance | — |
45 Permalloy MagAnn — frequently asked
What is 45 Permalloy MagAnn used for?
45 Permalloy MagAnn is typically used for small transformer laminations, relay cores, current transformer cores and magnetic amplifiers. In short: higher-induction permalloy grade; balances permeability and flux; needs final hydrogen anneal.
What is the yield strength of 45 Permalloy MagAnn?
45 Permalloy MagAnn has a typical yield strength of 170 MPa (24.7 ksi) and a tensile strength of 470 MPa (68.2 ksi) — weaker than 99% of steel grades. Strength varies by condition: see the 7 listed tempers.
Is 45 Permalloy MagAnn easy to machine?
Not especially — machinability is rated poor (30/100, worse than 89% of steel grades). Gummy and work-hardening — use sharp positive-rake carbide, heavy feed, low-to-moderate speed and flood coolant; leave a finish anneal after machining to restore magnetics.
Can 45 Permalloy MagAnn be welded?
Yes — weldability is rated good (60/100). TIG, laser and resistance welding are fine with matching Ni-Fe filler and low heat input, but the weld and HAZ lose permeability until the assembly is re-annealed in hydrogen.
What surface finishes work on 45 Permalloy MagAnn?
No anodising; protect with nickel or tin plating, chromate-free lacquer or an epoxy-coated shielding can, and handle annealed shields gently to preserve magnetic performance.
Can 45 Permalloy MagAnn be formed, bent or molded?
Annealed strip stamps, deep-draws and bends readily; avoid residual stress and never straighten a finished core, then hydrogen anneal parts on flat ceramic supports.
What is the maximum service temperature of 45 Permalloy MagAnn?
45 Permalloy MagAnn is rated for continuous use to about 400°C (752 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 45 Permalloy-ANN and 45 Permalloy-CR?
ANN is the default condition — standard stocked soft condition: formable and machinable, magnetic properties still to be developed by the customer's final anneal. CR: supplied hard for springy stampings, shims and for customers who stamp then anneal the finished part. Yield strength is 210 MPa in ANN versus 800 MPa in CR.
Sources
- ASM Handbook Vol.2 — Properties and Selection: Nonferrous Alloys and Special-Purpose Materials (Magnetically Soft Materials) — ASM International (1990)
- Soft magnetic Ni-Fe alloy (48–50 % Ni) strip datasheet — VACUUMSCHMELZE / Carpenter-type producer literature (2020)
- ASTM A753 — Standard Specification for Wrought Nickel-Iron Soft Magnetic Alloys (Type 2) — ASTM International (2019)
Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.