Buy 31CrMoV9 Nitriding Steel Bar / 1.8519 Alloy Steel Round Bars Online At Best Price in Mumbai

Element	Weight Range (%)	Metallurgical Function
Carbon ( $\text{C}$ )	0.28 â€“ 0.35	Delivers core strength, fatigue resistance, and high yield strength.
Chromium ( $\text{Cr}$ )	2.30 â€“ 2.70	Primary nitride former; builds a hard, wear-resistant surface case.
Molybdenum ( $\text{Mo}$ )	0.15 â€“ 0.25	Increases core hardenability and prevents temper brittleness.
Vanadium ( $\text{V}$ )	0.10 â€“ 0.25	Refines grain size and forms hard, heat-stable nitrides in the case.
Manganese ( $\text{Mn}$ )	0.40 â€“ 0.70	Deoxidizes and enhances through-section hardenability.
Silicon ( $\text{Si}$ )	$\le 0.40\text{ max}$	Deoxidizer during steel refining.
Phosphorus ( $\text{P}$ )	$\le 0.025\text{ max}$	Restricted for clean, high-fatigue microstructures.
Sulfur ( $\text{S}$ )	$\le 0.035\text{ max}$	Kept low for high transverse impact toughness.

Property	Core / Base Material (+QT State)	Post-Nitrided Surface Layer
Tensile Strength ( $\sigma_b$ )	800 â€“ 1000 MPa (up to 1100 MPa in thin ruling sections)	â€”
0.2% Yield Strength ( $\sigma_{0.2}$ )	$\ge 600\text{--}650\text{ MPa}$	â€”
Elongation ( $A_5$ )	$\ge 12\text{--}14\%$	â€”
Impact Energy (ISO-V)	$\ge 30\text{--}35\text{ J}$ (at +20Â°C)	â€”
Base Hardness	248 â€“ 302 HB (~260â€“315 HV)	â€”
Nitrided Surface Hardness	â€”	800 â€“ 950 HV1 ( $\approx 64\text{--}68\text{ HRC}$ )
Effective Case Depth	â€”	0.20 â€“ 0.60 mm (cycle-dependent)