Overview of 4Cr13 Steel

4Cr13 steel is a martensitic stainless steel characterized by high hardenability, excellent resistance to corrosion and hot oxidation, and good polishing properties. The material undergoes specific heat treatment: annealing at 750-800 C, hardening at 1000-1050 C, and tempering at 180-300 C to achieve its desired properties.

The steel is commonly used in precision mechanisms, automotive structures, plastic molds, and petrochemical applications due to its wear resistance and corrosion properties.

NOTE
Reference standards: 4Cr13 per GB/T 1220 and GB/T 20878; 40Cr13 per GB/T 3280.

Equivalent Materials

The European standard EN 10088-3 recognizes X39Cr13 (1.4031) as equivalent to Chinese grade 4Cr13 (40Cr13). Both materials exhibit similar characteristics: good corrosion resistance and high hardenability, excellent resistance to corrosion and hot oxidation, and suitability for precise mechanisms and structural applications.

Characteristics of 4Cr13 Steel

4Cr13 demonstrates impressive hardenability and excellent resistance to both corrosion and hot oxidation. It exhibits superior polishing properties compared to other martensitic stainless steels and maintains balanced mechanical properties across applications. The hardened and tempered steel achieves an HRC hardness of over 50, indicating suitability for high-load applications.

Uses of 4Cr13 Steel

  • Precision tool mechanisms requiring high wear resistance
  • Petrochemical industry components exposed to corrosive substances
  • Plastic mold manufacturing
  • Equipment requiring extended durability in harsh conditions

Physical Properties of 4Cr13 Steel

PropertyValue
Density (g/cm3) @ 20 C7.75
Melting point (C)1380
Specific heat capacity (kJ/Kg-K)0.46
Thermal conductivity (W/m-K)28.1
Linear thermal expansion (10-6/K), 0-100 C10.50
Linear thermal expansion (10-6/K), 0-500 C12.00
Electrical resistivity (ohm-mm2/m) @ 20 C0.590
Longitudinal modulus of elasticity (kN/mm2) @ 20 C215

Mechanical Properties of 4Cr13 Steel

PropertySpecification
HRC Hardness (quenched/tempered)50 min
Tensile strength Rm (N/mm2)235 min

Chemical Composition of 4Cr13 Steel

ElementContent (%)
Carbon (C)0.36 - 0.45
Silicon (Si)0.6
Manganese (Mn)0.8
Phosphorus (P)0.04
Sulfur (S)0.03
Nickel (Ni)(0.60)
Chromium (Cr)12.00 - 14.00
Molybdenum (Mo)-
Copper (Cu)-
Nitrogen (N)-