42CrMo4 Steel Billet/Bar: High-Strength Chromium-Molybdenum Steel
16MnCr5 is a low-carbon, low-alloy structural steel primarily utilized for case hardening or carburizing. This process creates a very hard wear-resistant surface (case) while retaining a softer, tougher core, making it ideal for components subject to both wear and shock loading. This grade is widely specified in the European Standard (EN 10084) and is often considered comparable to the American grades AISI 5115 / 5120.
The designation indicates that the steel contains approximately 0.16% Carbon, along with controlled additions of Manganese (Mn) and Chromium (Cr) to enhance hardenability.
ERST Group supplies 16MnCr5 in billet and bar form, catering specifically to the automotive, transmission, and general machinery sectors.
Key Characteristics and Performance
16MnCr5 is specifically engineered for excellent response to surface hardening heat treatments.
Key Characteristics
- High Core Toughness: The low carbon content in the core retains ductility and toughness, offering high resistance to fracture.
- High Surface Hardness: The controlled alloy content (Mn and Cr) allows the surface layer (case) to achieve high hardness (e.g., 60 HRC or higher) after carburizing and quenching.
- Good Wear Resistance: The hard case provides superior resistance to abrasion and friction.
- Good Machinability: In the soft annealed condition, it offers adequate machinability, facilitating easy shaping before final heat treatment.
Primary Applications
- Transmission Components: Gears, pinions, gear shafts, and drive chains.
- Automotive: Bushings, cams, piston pins, and heavy-duty roller bearings.
- Machinery: Parts requiring a hard surface for wear resistance and a tough core for shock loading, such as agricultural equipment components.
Standard Chemical Composition (EN 10084 Equivalent)
The chemistry of 16MnCr5 is balanced to ensure optimal carbon absorption during carburizing and sufficient hardenability during quenching.
16MnCr5 Steel Chemical Specification
| Element | Specification (%) | Role of the Element |
|---|---|---|
| Carbon (C) | 0.14 – 0.19 | Low carbon content enables subsequent carburization (C-absorption). |
| Manganese (Mn) | 1.00 – 1.30 | Increases hardenability and core strength. |
| Chromium (Cr) | 0.80 – 1.10 | Improves hardenability and wear resistance of the case. |
| Silicon (Si) | Max 0.40 | Residual element; small amounts act as a deoxidizer. |
| Phosphorus (P) | Max 0.035 | Impurity; strictly controlled. |
| Sulphur (S) | Max 0.035 | Impurity; strictly controlled. |
Forms and Delivery
16MnCr5 is supplied in forms optimized for the final machining and heat treatment processes.
- Billet: Semi-finished material used by specialized rolling mills to produce small-diameter bars or forgings.
- Round Bar: The most common finished form, supplied either hot-rolled or cold-drawn, and typically in the soft annealed condition to facilitate easy machining.
- Packaging: Bars are securely bundled with steel strapping, and specialized rust prevention is applied for long-distance transit.