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Engine Valve Materials
Every valve grade we work with is matched to a specific job in the engine — how hot it runs, how it’s loaded, and how long it needs to last. Tell us your engine specification and we’ll confirm the right grade for your application.
Intake Valve Steels
SUH3 (Silchrome 1)
C 0.40–0.50 · Si 2.00–3.00 · Mn 0.30–0.60 · Cr 8.00–10.00 · Fe balance
The standard hardened steel grade for intake valves, built for stem/tip wear resistance rather than extreme heat.
Key properties: High hardness, good fatigue resistance, cost-effective.
Applications: Passenger cars, two/three-wheelers, general-purpose engines.
SUH11 (Silchrome XB)
C 0.75–0.85 · Si 0.50 max · Mn 0.30–0.60 · Cr 16.00–18.00 · Mo 1.50–2.50 · V 0.20–0.40 · Fe balance
A harder, more wear-resistant step up from SUH3 for demanding intake applications.
Key properties: Higher hardness, resists temper softening, stable under heat treatment.
Applications: High-performance and higher-RPM intake valves.
EN8 / EN19
EN8: C 0.36–0.44 · Mn 0.60–1.00 · Si 0.10–0.40. EN19: C 0.35–0.45 · Mn 0.50–0.80 · Cr 0.90–1.50 · Mo 0.20–0.35
General engineering steels for light-duty, cost-sensitive valve applications.
Key properties: Adequate strength, good machinability, lower heat resistance.
Applications: Small stationary engines, low-cost aftermarket, general-purpose equipment.
Exhaust Valve Steels & Superalloys
EN52
C 0.35–0.50 · Mn 8–10 · Cr 19–21 · Ni 1.75–2.75 · N 0.35–0.50
Cost-effective exhaust steel for moderate-temperature service (~650–700°C).
Applications: Two/three-wheelers, naturally aspirated passenger vehicles.
21-2N
C 0.48–0.58 · Mn 8–10 · Cr 20–22 · Ni 1.50–2.75 · N 0.35–0.50
A mid-tier exhaust grade bridging EN52 and 21-4N — balanced hot strength and cost.
Applications: Mid-displacement passenger and commercial vehicle exhaust valves.
21-4N
C 0.48–0.58 · Mn 8–10 · Cr 20–22 · Ni 3.25–4.50 · N 0.38–0.50
The industry-standard exhaust valve steel across automotive and diesel applications (~700–750°C).
Applications: Passenger cars, commercial vehicles, two/three-wheelers, agricultural engines.
Nimonic 80A
Ni balance (~72–79) · Cr 18–21 · Ti 1.80–2.70 · Al 1.00–1.80 · Co 2.00 max
A superalloy for exhaust duty beyond what steel grades can reliably handle.
Applications: Turbocharged/supercharged engines, heavy-duty diesel, motorsport.
Nimonic 90
Ni balance (~55–60) · Cr 18–21 · Co 15–21 · Ti 2.00–3.00 · Al 1.00–2.00
A cobalt-enhanced superalloy reserved for the most extreme thermal duty.
Applications: Extreme motorsport, high-boost racing, specialty industrial engines.
Inconel 751
Ni balance (~70–74) · Cr 14–17 · Fe 5–9 · Ti 2.25–2.75 · Al 0.90–1.50
A functional equivalent to the Nimonic family, common in OEM programs specifying this grade.
Applications: High-performance and OEM exhaust valve programs.
“Nimonic” and “Inconel” are registered trade names of their respective owners — sourced grades are supplied as the named alloy or a confirmed equivalent.
Performance & Specialty Materials
Titanium Alloy (Ti-6Al-4V)
Ti balance (~88–91) · Al 5.50–6.75 · V 3.50–4.50 · Fe 0.30 max
A lightweight valve material used to cut reciprocating valvetrain mass.
Key properties: ~45–55% the density of steel, high strength-to-weight ratio, reduces valve float risk at high RPM.
Applications: Motorsport, racing, high-RPM performance builds.
Valve Seat & Tip Hardfacing Alloys
Applied to the seat/tip contact area of a steel or superalloy valve body — not a body material itself.
Stellite
Co balance (~50–60) · Cr 25–33 · W 3–17 (grade-dependent) · C 1.00–2.50
The premium hardfacing alloy for seat recession resistance.
Key properties: Exceptional hot hardness, outstanding wear/galling resistance.
Applications: Exhaust valve seat facing, LPG/CNG engines, heavy-duty vehicles.
Colmonoy
Ni balance (~70–80) · Cr 11–17 · B 2.00–3.50 · Si 3.00–4.50
A cost-competitive hardfacing alternative to Stellite.
Key properties: Strong abrasion resistance, lower deposition temperature, economical.
Applications: Standard-duty passenger vehicle and two/three-wheeler valve facing.
“Stellite” and “Colmonoy” are registered trade names — sourced equivalents are described as such where applicable.
Not Sure Which Grade You Need?
Tell us your engine specification — displacement, fuel type, aspiration, and duty cycle — and our engineering team will recommend the right material grade and confirm it against your OEM drawing or sample.