14CrNi6 Case Hardening Steel Forgings
Seamless rolled rings, gear and pinion shafts, discs, blocks, hollow bars and forged bars in 14CrNi6 / 17CrNi6-6 (1.5918) chromium–nickel carburising steel.
14CrNi6 is a chromium–nickel case hardening steel with about 1.5 % chromium, 1.5 % nickel and a low base carbon content. Carburising, quenching and low-temperature tempering give it a hard surface at 58–62 HRC over a core that stays tough. That combination is why gearbox builders use it for gears, pinion shafts and crankshafts in sections too large for a through-hardening grade.
In current European standards the grade sits in EN 10084 as 17CrNi6-6, material number 1.5918. It replaced the older DIN 17210 grade 15CrNi6 (1.5919). The name 14CrNi6 comes from IS 4432 and is still widely used in trade for the same chromium–nickel carburising steel.
Jiangyin Jiangnan Metal Co., Ltd. is an open-die forging works in Jiangyin, Jiangsu Province, China. We forge 14CrNi6 to customer drawings: rolled rings, shafts, discs, blocks and hollow sections, each supplied with an EN 10204 3.1 material certificate. Send drawings to sales@steelforgepieces.com or call +86 189 2135 9659.
14CrNi6 at a glance
| Steel type | Chromium–nickel case hardening (carburising) steel |
|---|---|
| Current EN grade | 17CrNi6-6 |
| Material number | 1.5918 |
| Replaced grade | 15CrNi6 / 1.5919 (DIN 17210, withdrawn) |
| Governing standard | EN 10084:2008, case hardening steels, technical delivery conditions |
| Nominal alloy content | 1.40–1.70 % Cr, 1.40–1.70 % Ni, no molybdenum |
| Case hardness after carburising | 58–62 HRC typical |
| Core tensile strength | up to 1200 MPa at 16 mm and below, hardened and tempered at 200 °C |
| Case hardening depth | 0.5–3.0 mm to customer specification |
| Forging temperature | 1100 °C down to 850 °C, then annealed |
| Main uses | Gears, pinion and gear shafts, crankshafts, camshafts, ring gears, bearing races |
Chemical composition of 14CrNi6
Composition follows EN 10084 for grade 17CrNi6-6. Figures are percentages by mass, balance iron.
| C | Si | Mn | P | S | Cr | Ni | Fe |
|---|---|---|---|---|---|---|---|
| 0.14–0.20 | ≤0.40 | 0.50–0.90 | ≤0.025 | ≤0.035 | 1.40–1.70 | 1.40–1.70 | Balance |
There is no deliberate molybdenum addition. That is the main compositional difference from 18CrNiMo7-6 (1.6587). Where IS 4432 governs, 14CrNi6 carries a narrower manganese range of 0.40–0.60 %, so check which standard the drawing calls out. Free-cutting variants with raised sulphur can be melted on request. The heat analysis for your order appears on the mill test certificate.
Mechanical properties and hardness
14CrNi6 arrives soft enough to machine and only develops its working properties during carburising and hardening. EN 10084 sets the hardness limits for each delivery condition.
Hardness in the delivery condition
| Delivery condition | Symbol | Brinell hardness, HBW |
|---|---|---|
| Treated to improve shearability | +S | ≤255 |
| Soft annealed | +A | ≤229 |
| Treated to hardness range | +TH | 175–229 |
| Ferrite–pearlite structure | +FP | 156–207 |
Properties after heat treatment
| Property | Value | Condition |
|---|---|---|
| Tensile strength, Rm | 1200 MPa | Nominal thickness 16 mm and below, hardened and tempered at 200 °C |
| Tensile strength, Rm | ≤600 MPa | Spheroidise annealed (+AC), machining condition |
| Reduction of area, Z | 57–62 % | Hardened and tempered |
| Surface hardness | 58–62 HRC | Carburised, quenched, tempered at 150–200 °C |
| Core hardness | 30–42 HRC | Depends on section size |
| Density | 7.85 g/cm³ | Room temperature |
| Modulus of elasticity | 210 GPa | Room temperature |
Core strength drops as section size goes up. Above roughly 100 mm, send us the drawing and the case hardening depth you need and we will confirm what core properties are realistic before you release the order.
Heat treatment of 14CrNi6
These are the working ranges we use on 14CrNi6 forgings. Each piece leaves the works with its heat treatment record.
| Operation | Temperature | Cooling and notes |
|---|---|---|
| Hot forging | 1100 to 850 °C | Finish above 850 °C, cool slowly, then anneal |
| Normalising | 850–880 °C | Air cool |
| Soft annealing | 650–700 °C | Furnace cool, gives 229 HBW or below |
| Intermediate annealing | 630–650 °C | Stress relief between machining stages |
| Carburising | 880–980 °C | Gas, pack or low-pressure carburising |
| Core hardening | 830–870 °C | Oil, water, hot bath or salt bath |
| Case hardening | 780–820 °C | Oil or martempering bath |
| Tempering | 150–200 °C | Air cool, hold 1 to 2 hours per 25 mm of section |
One thing to watch when forging this grade. At around 1.5 % nickel, 14CrNi6 is prone to hydrogen flaking, also called white spots. Forgings have to be cooled slowly and annealed after forging rather than air cooled straight off temperature. Skip that and the defects turn up later at ultrasonic inspection, by which point the machining is already paid for.
14CrNi6 forged products
Everything below is made as an open-die forging or a seamless rolled ring, to your drawing, rough machined or finish machined as you prefer.
Seamless rolled rings and forged rings
Ring gear blanks, bearing races, retaining rings and flanged rings, rolled close to final section so there is less to cut away and the grain follows the circumference.
Gear shafts, pinion shafts and spindles
Stepped and flanged shafts, bevel gear and crown wheel blanks, crankshaft and camshaft blanks for gearboxes and heavy transmissions.
Blocks, discs and plates
Forged discs, blocks and rectangular plates for gear blanks, die blocks and machined transmission housings.
Round, square, flat and hex bars
Forged bars in round, square, rectangular, flat and hexagonal section, cut to length, peeled or rough turned.
Hollow bars, sleeves and bushes
Trepanned and bored hollow sections, bushings, sleeves and forged tube for pinion housings and bearing carriers.
Cylinders, hubs, housings and shells
Barrels, casings, shells, hubs and housings forged from solid, with the machining allowance you specify.
How we supply it
| Delivery condition | As forged, normalised, annealed or rough machined |
|---|---|
| Machining | Rough turning, boring and finish machining to drawing |
| Testing | Chemical analysis, tensile and impact testing, hardness survey, ultrasonic inspection to the acceptance class you specify |
| Certification | EN 10204 3.1 material certificate with every delivery |
| Quantity | Single prototype pieces through to series production |
| Lead time | Quoted with the price, based on section size and heat treatment route |
Where 14CrNi6 is used
14CrNi6 gets specified when a part has a large cross section and has to survive surface wear and shock loading at the same time. Common jobs:
- Transmission and gearing: spur, helical and bevel gears, ring gears, crown wheels, pinion shafts and gear shafts
- Engine components: crankshafts, camshafts, connecting rods and gudgeon pins
- Heavy vehicle and off-highway: truck axle and differential parts, mining and construction machinery drives
- Wind and marine: gearbox shafts, planetary carriers and ring gear blanks
- Aerospace and defence: accessory drive gears and shafts where core toughness governs
- General mechanical engineering: bearing races, cams, pins, bushings and highly loaded machine elements
14CrNi6 equivalent grades
Several national designations cover the same chromium–nickel carburising steel. Here are the closest counterparts.
| Standard or country | Designation | Relationship |
|---|---|---|
| EN 10084, Europe | 17CrNi6-6 | Current governing grade |
| Werkstoff number | 1.5918 | Material number for 17CrNi6-6 |
| DIN 17210, Germany, withdrawn | 15CrNi6 / 1.5919 | Replaced by 17CrNi6-6 |
| IS 4432, India | 14CrNi6 | Same grade family |
| Older DIN usage | 14NiCr6, 16NiCr6 | Trade designations, same family |
| AISI / SAE, USA | 3115 | Closest Ni–Cr carburising grade, not identical |
| AISI / SAE, USA | 4320 / UNS H43200 | Often cross-referenced, but contains molybdenum |
Read this before you substitute. Neither American grade drops straight in. AISI 4320 carries a molybdenum addition that 14CrNi6 does not have, and that changes hardenability and the response to tempering. Use the table to start the conversation. Any substitution needs sign-off from whoever owns the design, and if you send us the original specification we will quote against the grade your drawing actually calls out.
How it compares with neighbouring grades
| Grade | Cr % | Ni % | Mo % | When to choose it |
|---|---|---|---|---|
| 14CrNi6 / 17CrNi6-6 | 1.40–1.70 | 1.40–1.70 | — | Good core toughness in small and medium sections without paying for molybdenum |
| 18CrNiMo7-6 | 1.50–1.80 | 1.40–1.70 | 0.25–0.35 | Larger sections and deeper hardening, the usual choice for wind and heavy gearboxes |
| 17CrNiMo6 | 1.50–1.80 | 1.40–1.70 | 0.25–0.35 | The former name for 18CrNiMo7-6, still seen on older drawings |
| AISI 4320 | 0.40–0.60 | 1.65–2.00 | 0.20–0.30 | North American drawings, leaner on chromium and carries molybdenum |
Machining, welding and surface treatment
Machine 14CrNi6 soft annealed (+A) or in the ferrite–pearlite condition (+FP), before carburising. Once the case is on at 58–62 HRC the only way to finish it is grinding, so all turning, drilling and gear cutting has to be done first, with grinding stock left on the functional surfaces.
Base carbon sits around 0.17 %, so the core welds with standard low-hydrogen procedures and preheat. A carburised case does not weld. If a part has to be welded after case hardening, mask those areas from the carburising atmosphere with copper plating or stop-off paint. Shot peening after case hardening lifts bending fatigue strength and is normal practice in gear roots.
Common questions about 14CrNi6
What is 14CrNi6 steel?
14CrNi6 is a low-carbon chromium–nickel case hardening steel with about 1.5 % chromium and 1.5 % nickel. Carburising, quenching and tempering take the surface to 58–62 HRC while the core stays tough, which suits gears, shafts and other parts that see wear and impact together.
What is the material number for 14CrNi6?
The material number is 1.5918, belonging to EN 10084 grade 17CrNi6-6. The older DIN 17210 grade 15CrNi6 carried 1.5919 and has been withdrawn. If a drawing says 14CrNi6 with no standard reference, ask the customer whether EN 10084 or IS 4432 applies, because the manganese range is not the same in both.
What is the chemical composition of 14CrNi6?
To EN 10084: 0.14–0.20 % carbon, up to 0.40 % silicon, 0.50–0.90 % manganese, up to 0.025 % phosphorus, up to 0.035 % sulphur, 1.40–1.70 % chromium and 1.40–1.70 % nickel, balance iron. No deliberate molybdenum addition.
What hardness does 14CrNi6 reach after carburising?
The surface typically reaches 58–62 HRC after carburising, quenching and low-temperature tempering. The core lands somewhere around 30–42 HRC depending on section size, with tensile strength up to 1200 MPa in sections of 16 mm and below tempered at 200 °C.
What is the difference between 14CrNi6 and 18CrNiMo7-6?
Both are chromium–nickel case hardening steels at similar chromium and nickel levels, but 18CrNiMo7-6 (1.6587) adds 0.25–0.35 % molybdenum and a little more carbon. The molybdenum buys deeper hardenability, so 18CrNiMo7-6 goes into very large sections such as wind turbine gearbox parts, while 14CrNi6 covers small and medium sections at lower alloy cost.
Is 14CrNi6 weldable?
The core welds with low-hydrogen consumables and preheat, because base carbon is low. A carburised case does not weld. Where welding has to happen after case hardening, mask those areas from carburising with copper plating or stop-off compound, and weld before final hardening wherever the design allows it.
Can 14CrNi6 be supplied as seamless rolled rings?
Yes. Jiangyin Jiangnan Metal Co., Ltd. rolls 14CrNi6 seamless rings for ring gear blanks and bearing races, alongside forged shafts, discs, blocks and hollow sections. Rings are rolled close to final section so the grain follows the circumference, which gives better fatigue life than a ring cut out of plate.
Who supplies 14CrNi6 forgings from China?
Jiangyin Jiangnan Metal Co., Ltd. is an open-die forging works at No.1 Chengxiqiao Road, Zhouzhuang Town, Jiangyin City, Jiangsu Province, China, forging 14CrNi6 to customer drawings with EN 10204 3.1 material certificates. Send an enquiry to sales@steelforgepieces.com or call +86 189 2135 9659.
What do you need in order to quote a 14CrNi6 forging?
The drawing or the finished dimensions, the quantity, the delivery condition you want, the case hardening depth if carburising is on our side, and any testing or certification requirements such as the ultrasonic acceptance class. Without a drawing, rough dimensions and the standard reference are enough for a budget price.
Where this data comes from
Composition and delivery hardness figures are taken from EN 10084:2008 for grade 17CrNi6-6. Heat treatment temperatures and the hardness figures after carburising come from that standard together with our own forging and heat treatment practice. Everything here is indicative. The mill test certificate issued with your delivery is the document that governs.
Document reference: 14CrNi6 datasheet, Jiangyin Jiangnan Metal Co., Ltd., steelforgepieces.com/Alloy-Steel/14CrNi6.html, revised September 2026.
Ask for a price on 14CrNi6 forgings
Send the drawing and we will come back with a price, a forging route and a delivery date. We forge to order, so there is no catalogue stock. Tell us what the part has to do and we will work out how to make it.