Types of Metals Used in Sheet Metal Fabrication - An Engineer’s Guide
Selecting the correct material is one of the most critical decisions in sheet metal fabrication. The right metal affects strength, formability, corrosion resistance, weight, cost, and long-term durability. This technical guide breaks down the most commonly used sheet metal alloys and their engineering properties, industry applications, and selection considerations.
Carbon Steel Tubing
Carbon Steel
Carbon steel contains 0.05%–2.0% carbon and is widely used for industrial and structural components due to its strength, weldability, and cost efficiency.
Common Grades: A36, 1018, 1045
Yield Strength: ~250–400 MPa (varies by grade)
Advantages
High strength-to-cost ratio
Predictable forming behavior
Strong weld performance
Tight dimensional stability (cold-rolled options)
Typical Applications
Structural brackets & frames
Machinery housings
Chassis components
Industrial enclosures
Engineering Note: Cold-rolled steel offers a smoother finish and tighter tolerances than hot-rolled steel.
Stainless Steel Dowels
Stainless Steel
Stainless steel contains ≥10.5% chromium, creating a passive oxide layer for corrosion protection. 304 and 316 are the most common fabrication grades.
Yield Strength: ~200–300 MPa (annealed)
Advantages
Corrosion and oxidation resistance
Hygienic, easy-to-clean surface
Strong at elevated temperatures
Typical Applications
Food & beverage equipment
Medical housings & assemblies
Marine & chemical applications
Engineering Note: 316 stainless is preferred for saltwater and chemical environments; stainless requires springback compensation during bending.
Aluminum Plates at a Drill Press
Aluminum
Aluminum offers superior strength-to-weight ratio and corrosion resistance.
Common Grades: 5052, 6061-T6
Yield Strength: 90–275 MPa
Advantages
Lightweight (2.7 g/cm³)
Excellent corrosion resistance
Good electrical and thermal conductivity
Typical Applications
Aerospace brackets & components
Enclosures & heat sinks
Marine structures
Engineering Note: Aluminum has a lower modulus of elasticity (~70 GPa), so designs require stiffness considerations.
Copper Wire - Spindle
Copper & Copper Alloys
Copper is used in applications requiring high electrical or thermal conductivity.
Yield Strength: ~70–200 MPa
Advantages
Superior conductivity
Antimicrobial surface properties
Excellent formability and solderability
Applications
Bus bars & EMI-shielded enclosures
Heat exchangers
Medical fixtures
Notes: Brass (Cu-Zn) improves machinability; bronze (Cu-Sn) excels in wear resistance for bushings and bearings.
Material Selection Checklist
When choosing metals for sheet metal fabrication, engineers should evaluate:
Strength & stiffness requirements
Corrosion/environmental conditions
Forming limits, bend radius, K-factor
Weldability & heat-affected zone behavior
Finish requirements (anodizing, passivation, powder coating)
Cost & lead time