Chrome Plated 38MnVS6 Rod (Q & T + I.H.)

The Chrome Plated 38MnVS6 Rod (Q & T + I.H.) is produced from premium 38MnVS6 micro-alloyed steel, processed with dual heat treatment—Quenched & Tempered plus Induction Hardened—followed by precision grinding and hard chrome plating. Q&T treatment gives the core a tough, high-strength matrix at 260–330 HB, while induction hardening produces a uniformly hard surface layer of 55–62 HRC at a controlled depth of 0.5–3.5 mm, further protected by an 850–1150 HV hard chrome deposit. Thanks to vanadium micro-alloying and fine grain structure, even the non-treated condition offers elevated strength. The dual treatment creates a “super-tough core + ultra-hard surface” gradient, engineered for heavy-duty, high-wear and fatigue-resistant hydraulic cylinders in construction machinery, commercial vehicle suspensions, heavy agricultural equipment and other demanding applications.

• Diameter: Mainly φ6–300 mm, larger custom sizes accepted

• Length: ≤8000 mm, custom lengths available

• Straightness: ≤0.2 mm/M

• Tolerance Grades: IT6–IT9

• OD Tolerance: According to ISO f7/f8/g6/h7/h8/h9; customized tolerances available upon request

• Ovality: Half of the tolerance value ISO f7

• Heat Treatment: Quenched & Tempered + Induction Hardened; customization options: Q&T only, I.H. only, QPQ, etc.

• Core Hardness (Q&T): 260–330 HB

• Surface Hardness (I.H.): 55–62 HRC

• Hardening Depth: 0.5–3.5 mm (adjustable)

• Surface Treatment: Hard Chrome Plated; customization options: EN Plating / Zinc Plating / Laser Cladding / Nitriding / QPQ / Thermal Spraying / Ceramic Coating

• Chrome Thickness: ≥10 μm, mainly 20–40 μm; can be over 100 μm for high-standard requirements

• Chrome Layer Hardness: 850–1150 HV (Vickers 100 gf)

• Surface Roughness: Ra≤0.2 μm, Rt≤2 μm

• Cohesion: No cracks, breaking or detaching after thermal shock (warming up at 300 ℃ and cooling in water)

• Porosity: Tested according to ISO 1456/1458, evaluation according to ISO 10289 rating 8–10. Under 10× magnification, no more than 30 micro white pin-holes per 1000 mm², with diameter not greater than approx. 0.1 mm

• Corrosion Resistance: Tested in neutral salt spray according to ISO 9227/ASTM B117 – 96 hours, rating 9 per ISO 10289

• Weldability: Poor (moderate carbon equivalent, with poor weldability in the induction-hardened zone and HAZ; if welding is required, the hardened layer must be mechanically removed beforehand, and strict high-temperature preheating and post-weld stress-relief tempering are mandatory; welding in load-bearing areas is absolutely prohibited)

• Packing: Anti-rust oil + cardboard tube/plastic sleeve + wooden case

• 38MnVS6 micro-alloyed steel with dual heat treatment creates a “high-strength tough core + high hardness surface” gradient

• Q&T core at 260–330 HB provides superior bending, impact and fatigue resistance with powerful load-bearing capacity

• Induction-hardened surface at 55–62 HRC with adjustable depth delivers excellent wear and indentation resistance

• Hard chrome overlay (850–1150 HV) provides a third protective layer, ensuring outstanding wear and corrosion protection for severe conditions

• Tight f7 tolerance and low ovality guarantee smooth motion and reliable sealing under heavy loads and high pressure

• 96-hour salt spray rating 9; combined corrosion protection withstands harsh environments

• Fully customizable dimensions, hardness profiles and processing deliver a cost-effective micro-alloyed steel enhancement solution for OEMs

In addition to standard specifications, we offer:

• Custom diameters and lengths, including extra-large sizes

• Tolerance grades and non-standard OD tolerances

• Higher straightness upon request

• Tailored combination of core hardness and induction-hardened case hardness

• Precise control of hardening depth

• Surface treatment alternatives: zinc plating, electroless nickel, laser cladding, nitriding, thermal spray, ceramic coating

• Extra-thick chrome layers beyond 100 μm

• Enhanced corrosion resistance and dedicated packing solutions

Limits and Fits Table

The table below provides shaft deviation values for commonly used tolerance grades f7, f8, g6, h7, h8, and h9 to assist your selection according to seal fits.

Chemical Composition

The table presents the standard chemical composition of frequently used materials such as CK45, 25Mn, 20#, ST52, 40Cr, 42CrMo4, 20MnV6 and 38MnVS6 for your reference.

Mechanical Properties

The following table lists reference tensile strength, yield strength, elongation and impact energy values for CK45 (hot-rolled, cold-drawn, Q&T), 25Mn, 20#, ST52, Q345D, 40Cr, 42CrMo4, 20MnV6 and 38MnVS6 under various conditions.