Stainless Steel 1.4123
EN 1.4123
1.4123 (X40CrMoVN16-2) is a vanadium- and nitrogen-alloyed 16% Cr martensitic stainless bearing steel that holds hardness and resists corrosion better than standard 440-series grades in aggressive bearing environments.
Reference datasheet — 1.4123 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 +A condition
1.4123 tempers and conditions
1.4123 is supplied in 5 conditions, soft to hard. +A is the default FabDigit quotes; the values on this page are for it.
Compare all 5 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Spheroidize annealed | Choose when the softest, most machinable structure is needed for deep drilling, thread rolling or cold forming of bearing-ring blanks. | 540 | 800 | 18 | 21 HRC | — |
+ADefault Annealed | Standard stock condition for machining of blanks before hardening; max hardness limited for turning and drilling. | 600 | 880 | 14 | 25 HRC | — |
+QT 50–54 HRC | Use for shafts, cages, pump and valve components where impact toughness matters more than peak wear resistance. | 1,500 | 1,750 | 7 | 52 HRC | — |
+QT high tempered ~500–525 °C (secondary hardening) 57–59 HRC | Pick for bearings and parts running hot (up to ~350–400 °C) or when dimensional stability after nitriding/coating cycles is required. | 1,800 | 2,100 | 4 | 58 HRC | — |
+QT 58–60 HRC | Standard bearing condition: maximum hardness and rolling-contact fatigue life for corrosion-exposed bearings and valve parts up to ~200 °C. | 1,850 | 2,200 | 3 | 59 HRC | — |
What is 1.4123?
1.4123 (X40CrMoVN16-2) is a vanadium- and nitrogen-alloyed 16% Cr martensitic stainless bearing steel that holds hardness and resists corrosion better than standard 440-series grades in aggressive bearing environments. It is supplied as annealed (+A, +AC) bar and in +QT52, +QT58 and +QT-HT hardened tempers, with 600 MPa yield, 880 MPa tensile, 14% elongation and 255 HB (25 HRC) in the default condition and service to 400 °C. It is effectively not weldable, machinability is low (score 35) and remelted bar is expensive with limited stock sizes; 1.4125 (440C) is the cheaper, less corrosion-resistant alternative. 1.4123 has a density of 7.68 g/cm³ (0.277 lb/in³), lighter than 94% of stainless steel grades. It melts at 1,400°C (2,552 °F). 1.4123 has a yield strength of 600 MPa (87 ksi) and a tensile strength of 880 MPa (128 ksi) — stronger than 86% of stainless steel grades. Elongation at break is 14% and the elastic modulus is 205 GPa (29.7 Msi).
What is 1.4123 used for?
- corrosion-resistant rolling bearings
- aerospace bearings
- precision instrument bearings
- valve seats
Advantages
- Polishes to a fine finish — 85/100, better than 97% of stainless steel grades
- High strength — 600 MPa (87 ksi), better than 86% of stainless steel grades
Limitations
- Difficult to weld — 20/100, worse than 95% of stainless steel grades
- Limited ductility — 14%, worse than 91% of stainless steel grades
- Needs corrosion protection — 42/100, worse than 90% of stainless steel grades
- Limited service temperature — 400°C (752 °F), worse than 78% of stainless steel grades
1.4123 properties
Typical room-temperature values for 1.4123-+A; bars are the position among stainless steel grades.
Physical3
1.4123 has a density of 7.68 g/cm³ (0.277 lb/in³), lighter than 94% of stainless steel grades. It melts at 1,400°C (2,552 °F).
Mechanical15
1.4123 has a yield strength of 600 MPa (87 ksi) and a tensile strength of 880 MPa (128 ksi) — stronger than 86% of stainless steel grades. Elongation at break is 14% and the elastic modulus is 205 GPa (29.7 Msi).
Thermal6
1.4123 is rated for continuous service to 400°C (752 °F). It conducts heat at 20 W/m·K (11.6 BTU/hr·ft·°F), better than 74% of stainless steel grades. Thermal expansion is 10.5 µm/m·K (5.83 µin/in·°F).
Electrical3
1.4123 conducts electricity at 2.5 % IACS, better than 75% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is fair (42/100), worse than 90% of stainless steel grades.
Sustainability4
Producing a kilogram of 1.4123 takes about 60 MJ of energy and emits 4.8 kg of CO₂ — more than 70% of stainless steel grades. Typical recycled content is 25%.
Manufacturability8
1.4123's machinability is fair (35/100, better than 51% of stainless steel grades); weldability poor (20/100); formability poor (30/100).
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. 1.4123 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with 1.4123
Is 1.4123 easy to machine?
Machine in the annealed/spheroidized condition with rigid setups, sharp coated carbide and generous coolant; after hardening only grinding, honing, EDM or hard turning with CBN is practical.
Can 1.4123 be welded?
Essentially not weldable for structural use — high carbon plus nitrogen gives hard, crack-prone martensite; if repair is unavoidable, preheat 250–300 °C and temper immediately after.
Can 1.4123 be formed, bent or molded?
Hot forge 1100–850 °C with slow cooling and immediate anneal; cold forming is limited to light straightening or thread rolling in the spheroidized state.
1.4123 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 |
|---|---|---|
| C | 0.35 – 0.45 | 0.4 |
| Si | ≤ 0.6 | 0.3 |
| Mn | ≤ 0.6 | 0.3 |
| P | ≤ 0.03 | |
| Slow S for rolling-contact fatigue cleanliness | ≤ 0.01 | |
| Cr | 15 – 16 | 15.5 |
| Mo | 1.5 – 2 | 1.8 |
| V | 0.2 – 0.4 | 0.3 |
| Npressurized/solution nitrogen, raises PREN and hardness retention | 0.15 – 0.25 | 0.2 |
| Niresidual | ≤ 0.5 | |
| Fe | balance |
What surface finishes work on 1.4123?
Passivate per AMS 2700 or ASTM A967 after grinding; the clean remelted structure polishes to a mirror finish and accepts PVD (TiN, DLC) or plasma nitriding below the tempering temperature.
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 1.4123 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- EN / DIN / Werkstoff-Nr.
- X40CrMoVN16-2
How much does 1.4123 cost?
1.4123 is a high-cost stainless steel ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
1.4123 — frequently asked
What is 1.4123 used for?
1.4123 is typically used for corrosion-resistant rolling bearings, aerospace bearings, precision instrument bearings and valve seats. In short: corrosion-resistant bearing steel; N-alloyed, better than 440C; high hardness retention.
What is the yield strength of 1.4123?
1.4123 has a typical yield strength of 600 MPa (87 ksi) and a tensile strength of 880 MPa (128 ksi) — stronger than 86% of stainless steel grades. Strength varies by condition: see the 5 listed tempers.
Is 1.4123 easy to machine?
Not especially — machinability is rated fair (35/100, better than 51% of stainless steel grades). Machine in the annealed/spheroidized condition with rigid setups, sharp coated carbide and generous coolant; after hardening only grinding, honing, EDM or hard turning with CBN is practical.
Can 1.4123 be welded?
Not readily — weldability is rated poor (20/100). Essentially not weldable for structural use — high carbon plus nitrogen gives hard, crack-prone martensite; if repair is unavoidable, preheat 250–300 °C and temper immediately after.
What surface finishes work on 1.4123?
Passivate per AMS 2700 or ASTM A967 after grinding; the clean remelted structure polishes to a mirror finish and accepts PVD (TiN, DLC) or plasma nitriding below the tempering temperature.
Can 1.4123 be formed, bent or molded?
Hot forge 1100–850 °C with slow cooling and immediate anneal; cold forming is limited to light straightening or thread rolling in the spheroidized state.
What is the maximum service temperature of 1.4123?
1.4123 is rated for continuous use to about 400°C (752 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
How much does 1.4123 cost?
1.4123 is a high-cost stainless steel ($$$$), pricier than about 78% 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 10088-3 Stainless steels — Technical delivery conditions for semi-finished products, bars, rods — CEN (2014)
- XD15NW nitrogen-alloyed martensitic stainless bearing steel — Aubert & Duval (2020)
- 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)
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.