Steel 1J34 CR+MA
Heat-treated state
GB 1J34
CR+MA = cold rolled then low-temperature stabilizing / field anneal
Use cold rolled strip given a long low-temperature (about 400–500 °C) stabilizing or magnetic-field anneal for linear inductors and magnetic modulators needing ageing-stable, constant permeability.
Values for the CR+MA condition
Other 1J34 tempers and conditions
1J34 is listed in 5 conditions; see the grade overview at 1J34.
Compare all 5 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Hot rolled / forged bar and rod, annealed | Order annealed hot rolled or forged bar for turned cores and magnetic shielding parts; 240 MPa yield and 32% elongation machine well, but finished parts still require a final magnetic anneal. | 240 | 540 | 32 | 125 HB | 3.8 % IACS |
MDefault Thermomechanically controlled processed | Standard delivery state: cold rolled strip given a hydrogen or vacuum magnetic anneal; form the part first, then run the final magnetic anneal to reach the specified constant-permeability band. | 260 | 560 | 30 | 130 HB | 3.8 % IACS |
Half-hard cold rolled strip | Choose half-hard cold rolled strip when parts need stiffness but must still be stamped; 620 MPa yield with 10% elongation, and magnetic properties come only from post-form annealing. | 620 | 750 | 10 | 200 HB | 3.8 % IACS |
CR+MAThis page Cold rolled then low-temperature stabilizing / field anneal | Use cold rolled strip given a long low-temperature (about 400–500 °C) stabilizing or magnetic-field anneal for linear inductors and magnetic modulators needing ageing-stable, constant permeability. | 760 | 880 | 6 | 22 HRC | 3.8 % IACS |
Hard cold rolled strip | Pick hard as-rolled strip when the high-reduction texture itself provides the constant-permeability effect: wound thin-strip cores, stiff parts, or work that cannot be annealed; 3% elongation. | 850 | 950 | 3 | 25 HRC | 3.7 % IACS |
What is 1J34 CR+MA?
1J34 CR+MA is 1J34 heat treated to CR+MA — use cold rolled strip given a long low-temperature (about 400–500 °C) stabilizing or magnetic-field anneal for linear inductors and magnetic modulators needing ageing-stable, constant permeability. 1J34 CR+MA has a yield strength of 760 MPa (110 ksi) and a tensile strength of 880 MPa (128 ksi) — stronger than 85% of steel grades. Elongation at break is 6% and the elastic modulus is 190 GPa (27.6 Msi). 1J34 CR+MA has a density of 8.2 g/cm³ (0.296 lb/in³), heavier than 98% of steel grades. It melts at 1,440°C (2,624 °F). M is the default condition FabDigit quotes; CR+MA is available on request or by drawing note.
Advantages
- Good corrosion resistance — 25/100, better than 92% of steel grades
- Polishes to a fine finish — 70/100, better than 87% of steel grades
- High strength — 760 MPa (110 ksi), better than 85% of steel grades
Limitations
- High embodied carbon — 11 kg CO₂/kg, worse than 100% of steel grades
- Poor heat conductor — 14 W/m·K (8.09 BTU/hr·ft·°F), worse than 99% of steel grades
- Limited ductility — 6%, worse than 97% of steel grades
- Difficult to machine — 33/100, worse than 86% of steel grades
- Low electrical conductivity — 3.8 % IACS, worse than 84% of steel grades
1J34 CR+MA properties
Typical room-temperature values for 1J34 CR+MA; 21 are specific to this condition. Other listed values are 1J34 reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
1J34 CR+MA has a density of 8.2 g/cm³ (0.296 lb/in³), heavier than 98% of steel grades. It melts at 1,440°C (2,624 °F).
Mechanical15
1J34 CR+MA has a yield strength of 760 MPa (110 ksi) and a tensile strength of 880 MPa (128 ksi) — stronger than 85% of steel grades. Elongation at break is 6% and the elastic modulus is 190 GPa (27.6 Msi).
Thermal6
1J34 CR+MA is rated for continuous service to 300°C (572 °F). It conducts heat at 14 W/m·K (8.09 BTU/hr·ft·°F), worse than 99% of steel grades. Thermal expansion is 10 µm/m·K (5.56 µin/in·°F).
Electrical3
1J34 CR+MA conducts electricity at 3.8 % IACS, worse than 84% of steel grades.
Chemical & Environmental3
Corrosion resistance is poor (25/100), better than 92% of steel grades.
Sustainability4
Producing a kilogram of 1J34 CR+MA takes about 130 MJ of energy and emits 11 kg of CO₂ — more than 100% of steel grades. Typical recycled content is 25%.
Manufacturability8
1J34 CR+MA's machinability is poor (33/100, worse than 86% of steel grades); weldability fair (48/100); formability poor (32/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 1J34 CR+MA
Is 1J34 easy to machine?
The austenitic matrix work-hardens quickly and tends to smear on the tool, so use sharp positive-rake tooling, lower speeds with a heavier feed, and flood coolant. Leave only small finishing allowances to avoid a deep stressed layer that degrades magnetic properties.
Can 1J34 be welded?
TIG, micro-plasma and laser welding are all usable in a clean, sulfur-free and oil-free condition. A full magnetic anneal after welding is mandatory to restore constant permeability.
Can 1J34 be formed, bent or molded?
Soft-condition strip stamps, deep-draws and winds well (formability score 70). The amount of deformation sets the final constant-permeability level, so the forming route must be fixed and matched to the final anneal.
What surface finishes work on 1J34?
Not anodizable; use nickel or tin plating, or a protective coating, for corrosion protection. Schedule the magnetic anneal (hydrogen or vacuum, 1050–1150 °C, controlled cooling rate) after all machining and deburring.
1J34 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 |
|---|---|---|
| Nigrade number denotes nominal nickel content | 33.5 – 35 | 34 |
| CoCo varies by producer/standard; confirm on mill certificate | 28 – 30 | 29 |
| Mn | 0.3 – 0.6 | 0.45 |
| Si | 0.15 – 0.3 | 0.2 |
| Clow carbon to ensure magnetic properties | ≤ 0.03 | 0.02 |
| S | ≤ 0.02 | — |
| P | ≤ 0.02 | — |
| Fe | balance | — |
1J34 CR+MA — frequently asked
What is 1J34 CR+MA used for?
1J34 CR+MA is typically used for wide-band linear chokes, loading coils and distortion-sensitive transformer cores. In short: constant-permeability Fe-Ni-Co alloy; flat mu versus field; linear inductor core grade.
What is the yield strength of 1J34 CR+MA?
1J34 CR+MA has a typical yield strength of 760 MPa (110 ksi) and a tensile strength of 880 MPa (128 ksi) — stronger than 85% of steel grades. Strength varies by condition: see the 5 listed tempers.
Is 1J34 CR+MA easy to machine?
Not especially — machinability is rated poor (33/100, worse than 86% of steel grades). The austenitic matrix work-hardens quickly and tends to smear on the tool, so use sharp positive-rake tooling, lower speeds with a heavier feed, and flood coolant. Leave only small finishing allowances to avoid a deep stressed layer that degrades magnetic properties.
Can 1J34 CR+MA be welded?
With care — weldability is rated fair (48/100). TIG, micro-plasma and laser welding are all usable in a clean, sulfur-free and oil-free condition. A full magnetic anneal after welding is mandatory to restore constant permeability.
What surface finishes work on 1J34 CR+MA?
Not anodizable; use nickel or tin plating, or a protective coating, for corrosion protection. Schedule the magnetic anneal (hydrogen or vacuum, 1050–1150 °C, controlled cooling rate) after all machining and deburring.
Can 1J34 CR+MA be formed, bent or molded?
Soft-condition strip stamps, deep-draws and winds well (formability score 70). The amount of deformation sets the final constant-permeability level, so the forming route must be fixed and matched to the final anneal.
What is the maximum service temperature of 1J34 CR+MA?
1J34 CR+MA is rated for continuous use to about 300°C (572 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 1J34-M and 1J34-Y?
M is the default condition — standard delivery state: cold rolled strip given a hydrogen or vacuum magnetic anneal; form the part first, then run the final magnetic anneal to reach the specified constant-permeability band. Y: pick hard as-rolled strip when the high-reduction texture itself provides the constant-permeability effect: wound thin-strip cores, stiff parts, or work that cannot be annealed; 3% elongation. Yield strength is 260 MPa in M versus 850 MPa in Y.
Sources
- ASM Handbook Vol.2 — Properties and Selection: Nonferrous Alloys and Special-Purpose Materials (Soft Magnetic Fe-Ni-Co Alloys) — ASM International (1990)
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.