Steel SECC
JIS SECC
SECC is JIS G3313 electro-galvanized (electroplated zinc) cold-rolled low-carbon steel sheet — an SPCC-type mild steel base with a thin, very uniform zinc layer (typically 2.5–5 µm per side) plus a chromate, phosphate or anti-fingerprint post-treatment.
Values for the HR condition
SECC tempers and conditions
SECC is supplied in 10 conditions, soft to hard. HR is the default FabDigit quotes; the values on this page are for it.
Compare all 10 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Annealed (soft) temper, electro-galvanized | Softest temper — pick for deep bends, hemming and severe forming where springback must be minimal. | 195 | 290 | 42 | 88 HB | 11 % IACS |
Cold rolled | Uncoated cold-rolled substrate condition — use when the part is painted/plated in-house and the mill zinc layer is not required. | 215 | 300 | 39 | 92 HB | 11 % IACS |
Standard temper, electro-galvanized | Mill standard skin-passed temper — the normal choice for bent chassis parts and painted panels. | 220 | 305 | 38 | 98 HB | 11 % IACS |
Electro-galvanized, no chromate passivation | Bare zinc surface with no passivation — used where the part is immediately painted, adhesive-bonded or must be Cr(VI)-free. | 220 | 305 | 38 | 98 HB | 11 % IACS |
Electro-galvanized with anti-fingerprint (organic/inorganic) top coat | Thin clear anti-fingerprint film over the zinc — used for unpainted visible IT/appliance chassis where handling marks and light humidity must be resisted. | 220 | 305 | 38 | 98 HB | 11 % IACS |
HRDefault Hot rolled | Choose hot-rolled stock when thickness and cost matter more than surface quality; tolerances and finish are coarser, with cold rolling or coating applied in later processing steps. | 240 | 340 | 36 | 105 HB | 11 % IACS |
1/8 hard (temper-rolled), electro-galvanized | Light temper rolling for flatter panels and slightly higher stiffness with moderate bending still possible. | 285 | 350 | 24 | 118 HB | 11 % IACS |
1/4 hard, electro-galvanized | Quarter-hard sheet for flat covers and shear/roll-formed profiles needing more stiffness than standard temper. | 340 | 395 | 17 | 133 HB | 11 % IACS |
1/2 hard, electro-galvanized | Half-hard sheet where flatness, dent resistance and higher yield matter and only gentle bends are needed. | 410 | 460 | 10 | 157 HB | 11 % IACS |
Full hard, electro-galvanized | Full-hard as-rolled temper — highest strength and flatness, essentially only for flat blanks, shearing and very light forming. | 540 | 570 | 3 | 185 HB | 11 % IACS |
Supply forms, finishes and certifications
Ways SECC is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.
| Option | What it is | Type |
|---|---|---|
SECC-P | Electro-galvanized, phosphate treated | Surface finish |
Galvanized | SECC as supplied, electro-galvanized + chromate, standard temper | Coating |
What is SECC?
SECC is JIS G3313 electro-galvanized (electroplated zinc) cold-rolled low-carbon steel sheet — an SPCC-type mild steel base with a thin, very uniform zinc layer (typically 2.5–5 µm per side) plus a chromate, phosphate or anti-fingerprint post-treatment. It is chosen for sheet-metal enclosures, chassis, brackets and appliance panels because it keeps the excellent formability, spot-weldability and flat, paint-ready surface of cold-rolled steel while adding modest sacrificial corrosion protection at low cost. Limits are the thin coating (far less outdoor durability than hot-dip galvanized/SGCC), zinc fume and coating loss at cut/welded edges, and a service ceiling set by the zinc and passivation layers rather than by the steel. SECC has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,500°C (2,732 °F). SECC has a yield strength of 240 MPa (34.8 ksi) and a tensile strength of 340 MPa (49.3 ksi) — weaker than 96% of steel grades. Elongation at break is 36% and the elastic modulus is 205 GPa (29.7 Msi).
What is SECC used for?
- Industrial enclosures
- Computer and server chassis
- Electrical cabinets and panels
- Appliance side and back panels
- Mounting brackets and trays
- Rack-mount hardware
- HVAC and duct panels
Advantages
- Ductile — tolerates forming and impact — 36%, better than 98% of steel grades
- Conducts heat well — 52 W/m·K (30 BTU/hr·ft·°F), better than 98% of steel grades
- High electrical conductivity — 11 % IACS, better than 98% of steel grades
- Tough — resists crack growth — 140 MPa·√m (127.4 ksi·√in), better than 94% of steel grades
- Forms and bends easily — 75/100, better than 90% of steel grades
Limitations
- Hard to polish — 35/100, worse than 99% of steel grades
- Low strength — 240 MPa (34.8 ksi), worse than 96% of steel grades
- High embodied carbon — 2.5 kg CO₂/kg, worse than 82% of steel grades
SECC properties
Typical room-temperature values for SECC-HR; bars are the position among steel grades.
Physical3
SECC has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,500°C (2,732 °F).
Mechanical16
SECC has a yield strength of 240 MPa (34.8 ksi) and a tensile strength of 340 MPa (49.3 ksi) — weaker than 96% of steel grades. Elongation at break is 36% and the elastic modulus is 205 GPa (29.7 Msi).
Thermal6
SECC is rated for continuous service to 400°C (752 °F). It conducts heat at 52 W/m·K (30 BTU/hr·ft·°F), better than 98% of steel grades. Thermal expansion is 12 µm/m·K (6.67 µin/in·°F).
Electrical3
SECC conducts electricity at 11 % IACS, better than 98% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (8/100), worse than 99% of steel grades.
Sustainability4
Producing a kilogram of SECC takes about 35 MJ of energy and emits 2.5 kg of CO₂ — more than 87% of steel grades. Typical recycled content is 25%.
Manufacturability7
SECC's machinability is good (62/100, better than 89% of steel grades); weldability excellent (88/100); formability very good (75/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the steel family
Yield strength against density for every steel grade FabDigit runs. SECC is highlighted; hover a dot for its name, or open the interactive family chart.
Working with SECC
Is SECC easy to machine?
Soft and gummy — punch, laser or shear rather than mill; use sharp tools, high rake and light feeds to avoid burrs and zinc smearing, and expect coating loss on all cut edges.
Can SECC be welded?
Excellent resistance spot/projection welding (use ~10–20 % higher current and more frequent tip dressing than bare CR); MIG/TIG needs fume extraction and post-weld zinc-rich touch-up because zinc burns off in the heat-affected zone.
Can SECC be formed, bent or molded?
Very good cold formability in A/S tempers — bends to 1T–2T, deep drawing possible in the soft temper; the zinc layer acts as a mild lubricant but heavy draws can flake it, so galling and die pick-up should be checked.
Manufacturability
The process limits FabDigit's quote engine applies to SECC. Design inside these and the part quotes instantly; outside them it routes to an engineer.
Sheet metal
| Formability | Excellent75 / 100 |
|---|---|
| Weldability | Fair88 / 100 |
| Bendable | Yes |
SECC 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 |
|---|---|---|
| CSPCC base per JIS G3141 | ≤ 0.15 | 0.06 |
| Mn | ≤ 0.6 | 0.3 |
| P | ≤ 0.1 | 0.02 |
| S | ≤ 0.04 | 0.02 |
| Zn coatingElectroplated zinc, ≥99 % Zn; typical coating mass 20/20 g/m² per side (≈2.8 µm), range 8–40 g/m² per JIS G3313 designations E8–E40 | — | |
| Febase steel | balance |
What surface finishes work on SECC?
Take as-supplied chromate or anti-fingerprint finish for indoor use; phosphate grade or a light alkaline clean plus conversion coat for powder coating; touch up cut edges, welds and drilled holes with zinc-rich primer for humid service.
Surface treatments FabDigit runs on steel parts — pick them in the quote configurator or call them out on the drawing. Each links to its datasheet in the surface-finish library (thickness, specs, call-out, material verdicts).
Plating
Black / Phosphate
Thermal Spray
Equivalent designations
Standards and trade names that resolve to Steel SECC in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- Also called
- Electro-Galvanized Cold-Rolled Steel
How much does SECC cost?
SECC is a standard-cost steel ($$), cheaper than about 71% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
SECC — frequently asked
What is SECC used for?
SECC is typically used for industrial enclosures, computer and server chassis, electrical cabinets and panels, appliance side and back panels, mounting brackets and trays and rack-mount hardware. In short: electro-galvanized commercial coil.
What is the yield strength of SECC?
SECC has a typical yield strength of 240 MPa (34.8 ksi) and a tensile strength of 340 MPa (49.3 ksi) — weaker than 96% of steel grades. Strength varies by condition: see the 10 listed tempers.
Is SECC easy to machine?
Reasonably — machinability is rated good (62/100, better than 89% of steel grades). Soft and gummy — punch, laser or shear rather than mill; use sharp tools, high rake and light feeds to avoid burrs and zinc smearing, and expect coating loss on all cut edges.
Can SECC be welded?
Yes — weldability is rated excellent (88/100). Excellent resistance spot/projection welding (use ~10–20 % higher current and more frequent tip dressing than bare CR); MIG/TIG needs fume extraction and post-weld zinc-rich touch-up because zinc burns off in the heat-affected zone.
What surface finishes work on SECC?
Take as-supplied chromate or anti-fingerprint finish for indoor use; phosphate grade or a light alkaline clean plus conversion coat for powder coating; touch up cut edges, welds and drilled holes with zinc-rich primer for humid service.
Can SECC be formed, bent or molded?
Very good cold formability in A/S tempers — bends to 1T–2T, deep drawing possible in the soft temper; the zinc layer acts as a mild lubricant but heavy draws can flake it, so galling and die pick-up should be checked.
What is the maximum service temperature of SECC?
SECC 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 SECC-HR and SECC-1?
HR is the default condition — choose hot-rolled stock when thickness and cost matter more than surface quality; tolerances and finish are coarser, with cold rolling or coating applied in later processing steps. SECC-1: full-hard as-rolled temper — highest strength and flatness, essentially only for flat blanks, shearing and very light forming. Yield strength is 240 MPa in HR versus 540 MPa in SECC-1.
How much does SECC cost?
SECC is a standard-cost steel ($$), cheaper than about 71% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Can FabDigit make parts in SECC?
Yes — SECC is available for sheet metal with instant online pricing. Upload a STEP file to get a price and a DFM check.
Sources
- JIS G 3313 — Electrolytic zinc-coated steel sheet and strip — JSA (2021)
- JIS G 3141 — Cold-reduced carbon steel sheet and strip (SPCC base) — JSA (2021)
- GB/T 15675 / GB/T 5213 equivalents for — SAC (2020)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels — ASM International (1990)
- ASM Handbook Vol.13B — Corrosion: Materials (zinc coatings) — ASM International (2005)
- Electro-galvanized coil (SECC/SECC-N/SECC-AF) product data — Nippon Steel / POSCO / Baosteel (2023)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.