Steel TRIP690
ASTM A1088 TRIP690
TRIP690 (HCT690T, A1088 TRIP690) is a mid-strength transformation-induced-plasticity sheet steel with 450 MPa yield, 720 MPa tensile, 26 % elongation and about 210 HB (96 HRB).
Reference datasheet — TRIP690 is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
Values for the CR condition
TRIP690 tempers and conditions
TRIP690 is supplied in 6 conditions, soft to hard. CR is the default FabDigit quotes; the values on this page are for it.
Compare all 6 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Hot rolled | Thicker gauges (≈2–6 mm) for chassis arms, wheel discs and suspension parts where cold-rolled thickness is insufficient. | 440 | 710 | 24 | 15 HRC | 8 % IACS |
Hot-dip galvanized | Most common automotive supply form: zinc-coated for cathodic corrosion protection of exposed structural stampings. | 445 | 715 | 25 | 17 HRC | 8 % IACS |
CRDefault Cold rolled | Standard uncoated cold-rolled TRIP690 coil/blank for painted or later-coated stampings and for laboratory formability work. | 450 | 720 | 26 | 210 HB | — |
Electrogalvanized | Thin, very uniform zinc layer applied without a thermal cycle — keeps the as-annealed TRIP mechanical properties and gives the best surface for visible panels. | 450 | 720 | 26 | 17 HRC | 8 % IACS |
Galvannealed | Choose when paint adhesion and spot-weldability of the coating matter more than maximum coating ductility (Zn-Fe layer powders on severe draws). | 455 | 720 | 24 | 17 HRC | 8 % IACS |
2 % pre-strained + paint-bake | In-service condition of a formed and painted part — work hardening plus bake hardening raise the yield strength markedly above the as-delivered value. | 580 | 760 | 20 | 20 HRC | 8 % IACS |
What is TRIP690?
TRIP690 (HCT690T, A1088 TRIP690) is a mid-strength transformation-induced-plasticity sheet steel with 450 MPa yield, 720 MPa tensile, 26 % elongation and about 210 HB (96 HRB). Its combination of high n-value and elongation suits deep-drawn or geometrically complex structural stampings; it is available cold-rolled, hot-rolled, bake-hardening and coated as +Z, +ZF or +ZE. Forming loads and springback are higher than mild steel, hole expansion is modest, the spot-weld current window is narrowed, and bare product corrodes quickly. DP600/DP780 are the usual alternatives when edge stretch matters more than draw depth. TRIP690 has a density of 7.8 g/cm³ (0.282 lb/in³), lighter than 87% of steel grades. It melts at 1,425°C (2,597 °F). TRIP690 has a yield strength of 450 MPa (65.3 ksi) and a tensile strength of 720 MPa (104 ksi) — stronger than 52% of steel grades. Elongation at break is 26% and the elastic modulus is 205 GPa (29.7 Msi).
What is TRIP690 used for?
- cross members
- longitudinal rails
- wheel discs
Advantages
- Forms and bends easily — 80/100, better than 93% of steel grades
- Ductile — tolerates forming and impact — 26%, better than 82% of steel grades
Limitations
- Limited service temperature — 200°C (392 °F), worse than 93% of steel grades
- Difficult to machine — 35/100, worse than 84% of steel grades
- Hard to polish — 45/100, worse than 84% of steel grades
TRIP690 properties
Typical room-temperature values for TRIP690-CR; bars are the position among steel grades.
Physical3
TRIP690 has a density of 7.8 g/cm³ (0.282 lb/in³), lighter than 87% of steel grades. It melts at 1,425°C (2,597 °F).
Mechanical14
TRIP690 has a yield strength of 450 MPa (65.3 ksi) and a tensile strength of 720 MPa (104 ksi) — stronger than 52% of steel grades. Elongation at break is 26% and the elastic modulus is 205 GPa (29.7 Msi).
Thermal6
TRIP690 is rated for continuous service to 200°C (392 °F). It conducts heat at 45 W/m·K (26 BTU/hr·ft·°F), better than 66% of steel grades. Thermal expansion is 12.5 µm/m·K (6.94 µin/in·°F).
Electrical3
TRIP690 conducts electricity at 8 % IACS, better than 55% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (12/100), worse than 53% of steel grades.
Sustainability4
Producing a kilogram of TRIP690 takes about 31 MJ of energy and emits 2.4 kg of CO₂ — more than 64% of steel grades. Typical recycled content is 25%.
Manufacturability7
TRIP690's machinability is fair (35/100, worse than 84% of steel grades); weldability good (62/100); formability very good (80/100).
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. TRIP690 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with TRIP690
Is TRIP690 easy to machine?
Rarely machined as sheet — trim, pierce and laser cut instead; use carbide tooling with generous clearance and expect high blanking loads (~2× mild steel) and rapid punch wear.
Can TRIP690 be welded?
Resistance spot welding is standard but needs a narrowed current window, higher electrode force and a post-weld tempering/downslope pulse to avoid brittle martensitic nuggets; laser welding gives good results with controlled carbon equivalent (CE ≈ 0.40–0.50).
Can TRIP690 be formed, bent or molded?
Very high n-value gives excellent stretch and deep-draw behaviour, but the TRIP effect raises forming loads and springback — plan 10–25 % more press tonnage than mild steel, use compensated dies and avoid excessive edge stretching (hole expansion is modest).
TRIP690 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 |
|---|---|---|
| Ccarbon enriches and stabilises retained austenite | 0.15 – 0.25 | 0.2 |
| SiSi-alloyed variant; suppresses carbide precipitation in bainite | 0.2 – 2 | 1.4 |
| Mn | 1.2 – 2.2 | 1.6 |
| AlAl partly replaces Si in galvanizable Al-TRIP variants | 0.02 – 2 | 0.5 |
| P | ≤ 0.12 | 0.02 |
| S | ≤ 0.02 | 0.01 |
| Nboptional micro-alloying for grain refinement | ≤ 0.06 | 0.03 |
| Tioptional | ≤ 0.06 | 0.02 |
| Cr+Mooptional hardenability additions | ≤ 0.6 | 0.1 |
| N | ≤ 0.01 | 0.01 |
| Fe | balance |
What surface finishes work on TRIP690?
Supply as +Z/+ZF/+ZE for corrosion protection; bare product must be phosphated and e-coated quickly, and high-Si grades need careful pickling/annealing atmosphere control for coating adhesion.
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).
Organic Coating
Black / Phosphate
Thermal Spray
Equivalent designations
Standards and trade names that resolve to Steel TRIP690 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- ASTM
- A1088 TRIP690
- Similar grades
- HCT690T
How much does TRIP690 cost?
TRIP690 is a budget-cost steel ($), cheaper than about 90% 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.
TRIP690 — frequently asked
What is TRIP690 used for?
TRIP690 is typically used for cross members, longitudinal rails and wheel discs. In short: strong strength-elongation balance; deep-draw capable AHSS; mid-range TRIP workhorse.
What is the yield strength of TRIP690?
TRIP690 has a typical yield strength of 450 MPa (65.3 ksi) and a tensile strength of 720 MPa (104 ksi) — stronger than 52% of steel grades. Strength varies by condition: see the 6 listed tempers.
Is TRIP690 easy to machine?
Not especially — machinability is rated fair (35/100, worse than 84% of steel grades). Rarely machined as sheet — trim, pierce and laser cut instead; use carbide tooling with generous clearance and expect high blanking loads (~2× mild steel) and rapid punch wear.
Can TRIP690 be welded?
Yes — weldability is rated good (62/100). Resistance spot welding is standard but needs a narrowed current window, higher electrode force and a post-weld tempering/downslope pulse to avoid brittle martensitic nuggets; laser welding gives good results with controlled carbon equivalent (CE ≈ 0.40–0.50).
What surface finishes work on TRIP690?
Supply as +Z/+ZF/+ZE for corrosion protection; bare product must be phosphated and e-coated quickly, and high-Si grades need careful pickling/annealing atmosphere control for coating adhesion.
Can TRIP690 be formed, bent or molded?
Very high n-value gives excellent stretch and deep-draw behaviour, but the TRIP effect raises forming loads and springback — plan 10–25 % more press tonnage than mild steel, use compensated dies and avoid excessive edge stretching (hole expansion is modest).
What is the maximum service temperature of TRIP690?
TRIP690 is rated for continuous use to about 200°C (392 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between TRIP690-CR and TRIP690-BH?
CR is the default condition — standard uncoated cold-rolled TRIP690 coil/blank for painted or later-coated stampings and for laboratory formability work. BH: in-service condition of a formed and painted part — work hardening plus bake hardening raise the yield strength markedly above the as-delivered value. Yield strength is 450 MPa in CR versus 580 MPa in BH.
How much does TRIP690 cost?
TRIP690 is a budget-cost steel ($), cheaper than about 90% 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.
Sources
- EN 10346 — Continuously hot-dip coated steel flat products (HCT690T) — CEN (2015)
- VDA 239-100 — Sheet Steel for Cold Forming (CR440Y690T-TR) — VDA (2016)
- SAE J2745 / A1088 High Strength Steel Sheet designations — SAE / AISI (2019)
- Advanced High-Strength Steels Application Guidelines v7 — WorldAutoSteel (2021)
- ASM Handbook Vol. 1 — Properties and Selection: Irons, Steels — ASM International (1990)
- Automotive TRIP 690 cold rolled / galvanized product data — ArcelorMittal / 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.