C-35 carbon steel

Introduction

We manufacture forging ingots, billets, and blooms in carbon steel specifically for C 35, designed for medium-to-high strength engineering applications where good hardness, toughness, and machinability are required.

C 35 is a medium carbon, unalloyed engineering steel that offers higher strength and hardness than lower carbon grades such as C 30 . With its balanced carbon and manganese content, C 35 is suitable for components subjected to moderate to heavy mechanical loads. It is widely used in automotive, machinery, and general engineering applications.

Chemical composition

Element	Content (%)	Function / effect
Carbon (c)	0.30 – 0.40	Provides increased strength and hardness
Manganese (mn)	0.60 – 0.90	Improves hardenability, strength, and toughness
Sulfur (s)	0.050 max	Improves machinability; controlled to avoid brittleness
Phosphorus (p)	0.050 max	Aids machinability; limited to maintain toughness
Silicon (si)	0.05 – 0.35	Acts as deoxidizer and enhances strength
Chromium (cr)	Nil	Not intentionally added
Nickel (ni)	Nil	Not present
Molybdenum (mo)	Nil	Not present
Other elements	—	No significant alloying additions

Mechanical properties (typical values, dependent on heat treatment and section size)

• tensile strength: approx. 520 – 680 MPa
• yield strength: approx. 300 – 420 MPa
• elongation: approx. 16 – 20%
• hardness (normalized): approx. 160 – 210 hb
• impact toughness: good
• fatigue resistance: moderate to good

Heat treatment

• annealing: improves machinability and relieves internal stresses
• normalizing: refines grain structure and improves strength and toughness
• quenching: increases hardness and tensile strength
• tempering: balances hardness with toughness and reduces brittleness
• C 35 is suitable for through hardening for medium load applications

Key features and benefits

• higher strength than low carbon steels
• good hardness and wear resistance
• good machinability in annealed condition
• uniform mechanical properties
• cost-effective medium carbon steel
• suitable for forging, machining, and fabrication

Typical applications

• shafts and axles
• gears and pinions (moderate load)
• bolts, studs, and fasteners
• forged engineering components
• automotive and agricultural parts

Equivalent steel grades

• C 35 (is)
• EN8 / EN8D (approximate)
• aisi 1035
• din c35 (1.0501)
• jis s35c

Why choose C 35 for your application?

C 35 is the ideal choice when higher strength and hardness than C 30  are required without the need for alloying elements. Its excellent response to heat treatment, good machinability, and cost-effectiveness make it a preferred material for general engineering and automotive components.

Comparison table for similar grades

Grade	Carbon (%)	Key applications	Heat treatment	Comments
C 35	0.30 – 0.40	Shafts, gears, forgings	Normalizing / q&t	Good strength and toughness
C 30	0.25 – 0.35	Fasteners, shafts	Normalizing	Lower strength than C 35
EN8	0.35 – 0.45	Engineering parts	Normalizing / q&t	Higher hardness
Aisi 1035	0.32 – 0.38	Automotive components	Normalizing / q&t	American equivalent
S35c	0.33 – 0.38	Machined parts	Normalizing	Japanese equivalent

Summary

C 35 is a medium carbon engineering steel offering a strong combination of strength, toughness, and machinability. It is widely used in machined and forged components subjected to moderate to heavy mechanical loads.