Project Description
S42027, also designated X30CrMoN15-1 (EN 1.4108, AMS 5898, Cronidur 30), is a high-nitrogen martensitic stainless steel produced via PESR, a specialized remelting process in which nitrogen is alloyed beyond normal solubility limits under elevated pressure. The resulting homogeneous microstructure contains finely dispersed carbonitrides rather than the coarse chromium carbides found in conventional 440C, yielding a unique combination of extreme hardness, exceptional corrosion resistance, and high fracture toughness. In the hardened and tempered condition, S42027 reaches 58–60 HRC while retaining corrosion resistance superior to 440C by approximately 100 mV in pitting potential—a performance gap that widens further in chloride-bearing and sour environments typical of oilfield operations. The nitrogen alloying also raises temper resistance to 475–500°C, allowing the alloy to retain hardness at elevated operating temperatures where 440C and 420 would soften. SHUNFU METAL supplies S42027 bar under ISO 9001:2015 and API Q1 certified quality systems, with every heat traced from PESR ingot to final shipment. The alloy’s PESR-only production route and tight nitrogen specification make S42027 a premium, application-critical grade for the petroleum sector’s most demanding wear-and-corrosion challenges—where failure of a single pump shaft, valve stem, or bearing can shut down production.
S42027 Bar in Oil & Gas Applications
S42027 bar machined into reciprocating pump shafts and plungers for chemical injection, methanol dosing, and produced water reinjection. Hardness ≥58 HRC resists abrasive wear from sand-laden fluids while PESR cleanliness delivers fatigue life under cyclic loading.
Gate, globe, and choke valve stems and seats in wellhead and Christmas tree assemblies. The combination of 60 HRC hardness and corrosion resistance exceeding 440C prevents galling and pitting in sour gas (H2S) and CO2 service.
Mandrels, centralizer subs, and setting tool components for wireline and coiled-tubing intervention. S42027 provides the hardness needed for repeated engagement cycles plus resistance to chloride-rich completion brines at downhole temperatures.
Races, balls, and rollers for mud pump and top-drive bearings. S42027’s PESR-derived microcleanliness and finely dispersed carbonitrides provide rolling-contact fatigue life exceeding 440C, even with seawater-contaminated lubricants.
Precision ball screws and linear actuator spindles for subsea valve actuation and remotely operated vehicle (ROV) manipulator arms. Dimensional stability after heat treatment ensures backlash-free operation over thousands of cycles.
High-strength studs, bolts, and nuts for subsea flanges, connectors, and clamp hubs. S42027 bar forged and machined into fasteners combines 60 HRC hardness with cathodic-protection compatibility in deepwater environments.
Reciprocating compressor valve plates, springs, and seat rings for gas gathering, gas lift, and vapor recovery units. High-cycle fatigue resistance and corrosion tolerance to wet sour gas make S42027 the preferred upgrade from 420 and 440C.
Thermowell tips, sample probe internals, and pressure transducer diaphragms exposed to sour process streams. The nitrogen-alloyed martensitic matrix resists pitting and crevice attack that would rapidly degrade 440C in the same service.
Plastic injection and extrusion screws for downhole chemical delivery systems and surface polymer-injection units for enhanced oil recovery (EOR). High wear resistance and corrosion tolerance to aggressive chemical packages.
S42027 Bar Supply Range
SHUNFU METAL stocks and produces S42027 bar in a broad dimensional envelope under ISO 9001 and API Q1 certified systems. All bars are supplied in the solution-annealed condition (typically 800–850°C, slow cooled), ready for machining and subsequent hardening by the end user. Incoming billets are verified by OES with nitrogen content confirmed by IGF analysis—both steps are mandatory because off-spec nitrogen directly compromises hardenability, corrosion resistance, and tempering response. SHUNFU METAL maintains dedicated S42027 forging and rolling campaigns segregated from standard martensitic grades to prevent mix-up and ensure full alloy identity preservation. Every bar ships with full EN 10204 3.1 certification. Custom-cut lengths, rough machining, and centerless grinding are available on request.
| Form | Condition | Diameter / Thickness | Length |
|---|---|---|---|
| Hot-Rolled Round Bar | Annealed | 5–350 mm | 1,000–6,000 mm |
| Forged Round Bar | Annealed | 100–800 mm | 500–4,000 mm |
| Hot-Rolled Flat Bar | Annealed | Thk 10–100 mm; W 20–200 mm | 1,000–4,000 mm |
| Forged Flat / Block | Annealed | Thk 20–340 mm; W up to 500 mm | 300–3,000 mm |
| Peeled / Turned Round Bar | Annealed | 5–200 mm | 1,000–6,000 mm |
Peeled/turned bars are supplied to h9–h11 tolerance for direct CNC machining without pre-machining. Larger forged diameters (up to 800 mm) are available on inquiry with extended lead times. SHUNFU METAL applies UT per ASTM A388 / EN 10228-3 on forged bars above 200 mm diameter as standard.
Chemical Composition of S42027
Composition below per ASTM F899, SAE AMS 5898, and EN 10088-3 (1.4108). SHUNFU METAL sources only fully certified PESR-produced heats with full-spectrum OES and IGF nitrogen verification at incoming inspection. The nitrogen level is the critical alloying parameter that distinguishes S42027 from conventional 420, 440C, and other martensitic Cr steels—it alone provides the combination of high hardness, corrosion resistance, and fracture toughness.
| Element | C | Si | Mn | Cr | Mo | Ni | N | P | S |
|---|---|---|---|---|---|---|---|---|---|
| Min (%) | 0.25 | — | — | 14.00 | 0.85 | — | 0.30 | — | — |
| Max (%) | 0.35 | 1.00 | 1.00 | 16.00 | 1.10 | 0.50 | 0.50 | 0.030 | 0.025 |
Iron balance. Nitrogen content is achieved through PESR processing under raised nitrogen partial pressure, producing a uniform martensitic microstructure free of coarse carbides. SHUNFU METAL verifies nitrogen by IGF on every heat. The Cr-Mo-N synergy is what gives S42027 its unique combination of 60 HRC hardenability and corrosion resistance exceeding that of 440C by approximately 100 mV (pitting potential in NaCl).
Mechanical Properties of S42027
Properties below represent typical values for S42027 bar. The alloy is supplied in the annealed condition for machinability and is hardened by the end user through austenitizing at 1020–1060°C, oil or gas quenching, and tempering at 150–500°C depending on the target hardness-toughness balance. SHUNFU METAL verifies annealed hardness on every batch before shipment and provides hardening response data from qualification heats. The alloy exhibits secondary hardening at tempering temperatures above 450°C due to fine Cr-Mo-N precipitate formation and retains temper resistance up to 500°C.
| Condition | Tensile Strength Rm | Yield Strength Rp0.2 | Elongation A5 | Hardness |
|---|---|---|---|---|
| Annealed (as-supplied) |
750–950 MPa | 500–650 MPa | ≥ 18 % | 250–310 HB ∼28–33 HRC |
| Hardened + Tempered (low-temp temper 150–200°C) |
1,900–2,100 MPa | 1,500–1,800 MPa | 4–8 % | 58–60 HRC |
| Hardened + Tempered (high-temp temper >450°C) |
1,400–1,600 MPa | 1,100–1,300 MPa | 8–14 % | 50–55 HRC |
Austenitizing: 1020–1060°C, hold 15–30 min, oil quench or gas quench. Deep cryogenic treatment at −80°C or −196°C between quenching and tempering is recommended to maximize hardness and dimensional stability by transforming retained austenite. Tempering at 150–200°C yields maximum hardness (58–60 HRC); tempering above 450°C activates secondary hardening via nitride/carbonitride precipitation. SHUNFU METAL provides hardness response and hardenability curves from qualification heats on request. Elastic modulus at room temperature: approximately 215 GPa.