Stainless Steel 1.4525
EN 1.4525
1.4525 (GX5CrNiCu16-4) is a copper-bearing 16Cr-4Ni martensitic cast stainless steel with precipitation-hardening capability, available solution treated (+AT) and in the +QT1 and +QT2 aged conditions.
Reference datasheet — 1.4525 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 +QT1 condition
1.4525 tempers and conditions
1.4525 is supplied in 3 conditions, soft to hard. +QT1 is the default FabDigit quotes; the values on this page are for it.
Compare all 3 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
+QT1Default Solution treated ~1020–1070 °C, quenched and precipitation aged… | Default condition for pump casings, impellers and valve bodies where toughness, weld repairability and SCC resistance matter more than peak strength. | 620 | 870 | 20 | 26 HRC | — |
Solution annealed | Interim condition supplied when the fabricator will machine, weld-repair and then age the casting to the final QT class. | 750 | 1,000 | 12 | 34 HRC | 2.1 % IACS |
Solution treated ~1020–1070 °C, quenched and precipitation aged… | Choose when higher yield strength, wear resistance and cavitation resistance are required (impellers, wear rings, high-pressure valve trim) and service is not aggressively chloride-bearing. | 900 | 1,050 | 14 | 35 HRC | — |
What is 1.4525?
1.4525 (GX5CrNiCu16-4) is a copper-bearing 16Cr-4Ni martensitic cast stainless steel with precipitation-hardening capability, available solution treated (+AT) and in the +QT1 and +QT2 aged conditions. It is chosen when a casting needs higher strength than standard CA-type grades: 620 MPa yield, 870 MPa tensile, 20 % elongation and 265 HB (26 HRC), with a corrosion resistance score of 62. Typical forms are sand and investment castings for pumps and valves. Maximum service temperature is 300 °C, lower than 1.4421 or CA6NM, and machinability is moderate (score 45); where weldability matters more than strength, 1.6982/CA6NM is the nearer choice. 1.4525 has a density of 7.8 g/cm³ (0.282 lb/in³), heavier than 50% of stainless steel grades. It melts at 1,400°C (2,552 °F). 1.4525 has a yield strength of 620 MPa (89.9 ksi) and a tensile strength of 870 MPa (126 ksi) — stronger than 88% of stainless steel grades. Elongation at break is 20% and the elastic modulus is 197 GPa (28.6 Msi).
What is 1.4525 used for?
- High-strength pump components
- Valve stems and trim
- Shafts requiring aging treatment
Advantages
- High strength — 620 MPa (89.9 ksi), better than 88% of stainless steel grades
- Easy to machine — 45/100, better than 84% of stainless steel grades
Limitations
- Limited service temperature — 300°C (572 °F), worse than 90% of stainless steel grades
- Limited formability — 20/100, worse than 86% of stainless steel grades
- Limited ductility — 20%, worse than 79% of stainless steel grades
1.4525 properties
Typical room-temperature values for 1.4525-+QT1; bars are the position among stainless steel grades.
Physical3
1.4525 has a density of 7.8 g/cm³ (0.282 lb/in³), heavier than 50% of stainless steel grades. It melts at 1,400°C (2,552 °F).
Mechanical16
1.4525 has a yield strength of 620 MPa (89.9 ksi) and a tensile strength of 870 MPa (126 ksi) — stronger than 88% of stainless steel grades. Elongation at break is 20% and the elastic modulus is 197 GPa (28.6 Msi).
Thermal6
1.4525 is rated for continuous service to 300°C (572 °F). It conducts heat at 17.5 W/m·K (10.1 BTU/hr·ft·°F), better than 72% of stainless steel grades. Thermal expansion is 10.8 µm/m·K (6 µin/in·°F).
Electrical3
1.4525 conducts electricity at 2.2 % IACS, worse than 61% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is good (62/100), worse than 52% of stainless steel grades.
Sustainability4
Producing a kilogram of 1.4525 takes about 53 MJ of energy and emits 4.6 kg of CO₂ — less than 67% of stainless steel grades. Typical recycled content is 65%.
Manufacturability8
1.4525's machinability is fair (45/100, better than 84% of stainless steel grades); weldability good (65/100); formability poor (20/100).
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 stainless steel family
Yield strength against density for every stainless steel grade FabDigit runs. 1.4525 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with 1.4525
Is 1.4525 easy to machine?
Machine in the overaged +QT1 (or solution-treated) state with rigid setups, sharp carbide tooling, positive rake and generous coolant; work-hardening and gummy chips make low speed/high feed preferable, and finish-machining after final ageing should allow ~0.1 % dimensional change.
Can 1.4525 be welded?
Readily weld-repaired with matching 630/17-4 filler (AWS ER630) using low heat input; preheat 100–150 °C for heavy sections and always re-solution + re-age (or at minimum re-age) after welding to restore properties.
Can 1.4525 be formed, bent or molded?
Cast to shape only — sand or investment casting with adequate feeding; the alloy is not cold-formed, and hot straightening must be followed by full solution treatment and ageing.
1.4525 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 |
|---|---|---|
| CGX5 designation | ≤ 0.07 | 0.05 |
| Si | ≤ 0.8 | 0.5 |
| Mn | ≤ 1 | 0.6 |
| P | ≤ 0.04 | 0.02 |
| S | ≤ 0.03 | 0.01 |
| Cr | 15 – 17 | 16 |
| Ni | 3 – 5 | 4 |
| Cuprecipitation-hardening element (ε-Cu) | 3 – 4 | 3.5 |
| Nbstabiliser; some specs require Nb ≥ 5×C | 0.15 – 0.45 | 0.28 |
| Mooptional / residual | ≤ 0.8 | 0.3 |
| Fe | balance |
What surface finishes work on 1.4525?
Passivate per ASTM A967 (nitric or citric) after machining; polishes well to bright finishes, accepts hard chrome or nitriding for wear surfaces, and must not be anodized.
Surface treatments FabDigit runs on stainless 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).
Passivation
Organic Coating
Thermal Spray
Equivalent designations
Standards and trade names that resolve to Stainless Steel 1.4525 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- EN / DIN / Werkstoff-Nr.
- GX5CrNiCu16-4
How much does 1.4525 cost?
1.4525 is a premium-cost stainless steel ($$$), cheaper than about 51% 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.
1.4525 — frequently asked
What is 1.4525 used for?
1.4525 is typically used for high-strength pump components, valve stems and trim and shafts requiring aging treatment. In short: precipitation-hardening cast stainless; highest strength CA-family casting; copper-bearing 16Cr-4Ni.
What is the yield strength of 1.4525?
1.4525 has a typical yield strength of 620 MPa (89.9 ksi) and a tensile strength of 870 MPa (126 ksi) — stronger than 88% of stainless steel grades. Strength varies by condition: see the 3 listed tempers.
Is 1.4525 easy to machine?
Reasonably — machinability is rated fair (45/100, better than 84% of stainless steel grades). Machine in the overaged +QT1 (or solution-treated) state with rigid setups, sharp carbide tooling, positive rake and generous coolant; work-hardening and gummy chips make low speed/high feed preferable, and finish-machining after final ageing should allow ~0.1 % dimensional change.
Can 1.4525 be welded?
Yes — weldability is rated good (65/100). Readily weld-repaired with matching 630/17-4 filler (AWS ER630) using low heat input; preheat 100–150 °C for heavy sections and always re-solution + re-age (or at minimum re-age) after welding to restore properties.
What surface finishes work on 1.4525?
Passivate per ASTM A967 (nitric or citric) after machining; polishes well to bright finishes, accepts hard chrome or nitriding for wear surfaces, and must not be anodized.
Can 1.4525 be formed, bent or molded?
Cast to shape only — sand or investment casting with adequate feeding; the alloy is not cold-formed, and hot straightening must be followed by full solution treatment and ageing.
What is the maximum service temperature of 1.4525?
1.4525 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.
How much does 1.4525 cost?
1.4525 is a premium-cost stainless steel ($$$), cheaper than about 51% 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 10283 — Corrosion resistant steel castings (GX5CrNiCu16-4, 1.4525) — CEN (2010)
- EN 10213 — Steel castings for pressure purposes — CEN (2016)
- ASTM A747/A747M — Steel Castings, Stainless, Precipitation Hardening (CB7Cu-1) — ASTM (2021)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels, and High-Performance Alloys — ASM International (1990)
- ASM Handbook Vol.13B — Corrosion: Materials — ASM International (2005)
- Steel Founders' Society of America — Cast stainless steel property data — SFSA (2019)
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.