C-45

Grade Introduction

The range of products of C45 Round Bar which we offer to our customers are of high quality and these round bars are used for making machineries and OEM Auto components. These products have been made keeping in mind the quality parameters which have been set by the industry in the market. C45 Steel Round Bars are always supplied with the test certificates and can be supplied in bulk quantity as well as retail quantity as per customers requirements. C45 round bars are supplied by us to various engineering and forging industries.

AISI C45 steel is medium tensile steel supplied in the black hot rolled or normalized condition. It has Brinell hardness ranging between 170 and 210 and tensile strength of 570 – 700 MPa. AISI C45 steel has good machinability, good weldability, and high strength and impact properties in either the normalized or hot rolled condition. C45 steel has a low through-hardening capability with only sections of size around 60 mm being recommended as suitable for tempering and through-hardening. However, it can be efficiently flame or induction hardened in the normalized or hot rolled condition to obtain surface hardnesses in the range of Rc 54 – Rc 60 based on factors such as section size, type of set up, quenching medium used etc.

Grade Application:

DIN C45 round bar steel material and steel plate C45, flats are widely used in all industry for uses which require more strength and wear resistance than the low carbon mild steel.

Quenched and subsequently tempered steel for C45 steel grade round bar, steel plate, flat and square is used for axles, bolts, forged connecting rods, crankshafts, torsion bars, light gears, guide rods, screws, forgings, wheel tyres, shafts, sickles, axes, knives, wood working drills, hammers, etc.

Our Supply Range

Chemical Composition

The following table shows the chemical composition of C45 steel:

Element C Mn P S Fe
Content(%) 0.420 – 0.50 0.60-0.90 ≤ 0.040 ≤ 0.050 98.51-98.98

Mechanical Properties

The mechanical properties of annealed DIN C45 carbon steel are outlined in the table below

  • Tensile strength σb (MPa): ≥600 (61)
  • Yield strength σs (MPa): ≥355 (36)
  • Elongation δ5 (%): ≥23
  • Reduction of area ψ (%): ≥55
  • Impact energy Akv (J): ≥98
  • Impact toughness αkv (J / cm2): ≥49 (5)
  • Hardness: no heat treatment, ≤229HB; annealed steel, ≤197HB

Hardness:

Min. 55 HRC

Heat treatment:

Heat treatment temperatures, including rate of heating, cooling and soaking times will vary due to factors such as the shape and size of each C45 steel component. Other considerations during heat treatment include the type of furnace, quenching medium and work piece transfer facilities. Please consult your heat treatment provider for full guidance on heat treatment of C45 carbon steel. 

Hardening:

Heat the component slowly to 820-860°C and allow it to be heated through. Quench in oil or water. 

Tempering:

Temper immediately after quenching whilst tools are still hand warm. Re-heat the C45  to the tempering temperature then soak for one hour per 25 millimeter of total thickness (2 hours minimum) Cool in air. For most applications temper between 550-660°C. 

Physical Properties:

  • Modulus of elasticity [103 x N/mm2]: 205
  • Density [g/cm3]: 7.85
  • Specific heat capacity[J/g.K]: 0.48

Thermal Properties

Properties T (°C) Treatment
Thermal Conductivity (W/m-K) 42.7 100
Specific Heat (J/kg-K) 477 50-100

Forging Properties:

Preheat the steel carefully, then raise the temperature to 1100°C for forging. Do not forge below 850°C. After forging cool slowly, preferably in a furnace. 

Stress Relieving:

  • Heat to 550°C – 660°C (1022°F – 1220°F)
  • Hold until the temperature is uniform
  • Soak for 1 hour per 25mm of section
  • Cool in still air

Normalizing

Normalizing:  840 – 880°C/air

Annealing:

Heat slowly to 680-710°C, soak well. Cool slowly in the furnace

Density

Properties T (°C) Treatment
Density (*1000 kg/m3) 7.7-8.03 25

Machinability:

This grade of alloy is readily machined following suitable cooling from forging or subsequent heat treatment.