Forging is commonly performed on metals that can withstand high pressure and deformation, such as steel, aluminum, copper, and their alloys. These materials are chosen because they offer good strength, ductility, and durability after forging.

Materials Used for Forging

Forging is the process of shaping metal by compressive forces, usually with a hammer or press. The choice of material is critical because it determines forgeability, mechanical properties, and final performance of the component. Most materials suitable for forging are metals with good ductility and malleability.

Materials used in forging can be broadly classified into:

Ferrous Metals (Iron-based)
Non-Ferrous Metals (Non-iron-based)

1. Ferrous Metals

Ferrous metals are iron-based metals, widely used because of their strength, toughness, and high-temperature resistance.

A. Carbon Steel

Composition: Iron + Carbon (0.2% – 2%)
Types:
- Low Carbon Steel (0.2–0.3%) – good ductility, used for shafts, bolts, rods.
- Medium Carbon Steel (0.3–0.6%) – moderate strength, used for gears, crankshafts.
- High Carbon Steel (0.6–2%) – high strength and wear resistance, used for cutting tools, dies, punches.
Forging Properties:
- Excellent forgeability at high temperatures.
- Can be heat-treated for hardness or toughness.

B. Alloy Steel

Carbon steel + alloying elements (Cr, Ni, Mo, Mn, V, etc.)
Examples: 4140, 4340 steel
Applications: Automotive parts, aerospace components, high-strength shafts.
Advantages:
- Higher strength than plain carbon steel
- Good toughness and fatigue resistance
- Can be heat-treated

C. Stainless Steel

Contains chromium (≥11%) for corrosion resistance
Types: Austenitic, Ferritic, Martensitic
Applications: Chemical industry, food processing, surgical instruments, aerospace.
Forging Properties:
- More difficult to forge than carbon steel
- Requires higher temperature and slower cooling

D. Cast Iron (Rarely Forged)

High carbon content (>2%)
Brittle; usually not forged, but ductile iron can be partially forged in specialized applications.

2. Non-Ferrous Metals

Non-ferrous metals are non-iron-based metals. They are usually lightweight, corrosion-resistant, and ductile, suitable for forging.

A. Aluminum and Aluminum Alloys

Lightweight and corrosion-resistant
Good thermal and electrical conductivity
Applications: Aerospace parts, automotive components, marine components
Forgeability:
- Excellent at moderate temperatures
- Cannot withstand very high loads like steel

B. Copper and Copper Alloys

Includes bronze (Cu + Sn) and brass (Cu + Zn)
High corrosion resistance and ductility
Applications: Bearings, bushings, marine hardware, decorative items
Forgeability:
- Soft and ductile at room temperature
- Can be forged hot for complex shapes

C. Titanium and Titanium Alloys

High strength-to-weight ratio
Excellent corrosion resistance
Applications: Aerospace, biomedical implants, high-performance automotive parts
Forgeability:
- Requires high temperature forging (~900°C)
- Difficult to work due to reactivity and high hardness at lower temperatures

D. Nickel Alloys

Excellent heat resistance and corrosion resistance
Applications: Turbine blades, aerospace, chemical industries
Forgeability:
- Can be hot-forged at very high temperatures
- Expensive but critical for high-performance components

4. Factors Determining Material Choice for Forging

Forgeability
- Ability of material to deform without cracking.
- Low-carbon steels, aluminum, copper are highly forgeable.
Mechanical Properties
- Strength, toughness, hardness, fatigue resistance.
- Alloy steels and titanium are preferred for high-stress applications.
Corrosion Resistance
- Stainless steel, titanium, and nickel alloys resist corrosion.
Temperature Resistance
- Some metals require hot forging (steel, titanium), while others can be cold-forged (aluminum, copper).
Cost
- Steel and aluminum are economical.
- Titanium and nickel alloys are expensive but necessary for aerospace or high-performance parts.

5. Summary Table of Common Forging Materials

Material	Forgeability	Applications	Notes
Low Carbon Steel	Excellent	Shafts, bolts, rods	Good ductility
Medium/High Carbon Steel	Good	Gears, crankshafts	Can be heat-treated
Alloy Steel	Good	Automotive, aerospace	High strength & toughness
Stainless Steel	Moderate	Food, chemical, surgical	Corrosion-resistant
Aluminum & Alloys	Excellent	Aerospace, automotive	Lightweight, corrosion-resistant
Copper & Alloys	Excellent	Bearings, bushings, marine	Good ductility
Titanium & Alloys	Moderate	Aerospace, biomedical	High strength, expensive
Nickel Alloys	Moderate	Turbine blades, chemical	Heat & corrosion resistant

In Simple Words

Metals suitable for forging are generally ductile and malleable, like steel, aluminum, copper, titanium, and their alloys. Steel is the most common, while special applications use titanium or nickel alloys for strength, corrosion, and heat resistance.