Common Sheet Metal Materials: Properties, Grades & Selection Guide
Sheet metal material selection during product design impacts the sheet metal part design, manufacturing process, cost, and part performance. This is a short reference tool to help you choose the best material for your next sheet metal project. It specifies key characteristics such as tensile strength, elongation, and hardness to ensure you have the best material for your part’s application. It even includes details on material thickness and finish possibilities.
There are various types of materials. Each material has its advantages, limitations, and applications. Product functional & aesthetic requirements and cost have an impact on the selection of a sheet metal material. Material choices should always be validated against your specific design requirements before production. When selecting sheet metal thickness and material type, keep the following factors in mind:
- Weight constraints.
- Cost constraints.
- Corrosion resistance requirements.
- Assembly Process.
- Availability of material.
Find the right material Precisely
Stainless Steel Sheet (SUS)
Stainless steel plate, also known as stainless, corrosion-resistant steel, is a corrosion-resistant alloy steel containing more than 10.5% chromium. It is a type of steel that is resistant to weak corrosive media such as air, steam, and water, as well as chemically corrosive media such as acid, alkali, and salt.
In practice, steel that is resistant to weak corrosive media is typically referred to as stainless steel, whereas steel that is resistant to chemical media corrosion is referred to as acid-resistant steel. Austenitic stainless steel is the most widely used grade of stainless steel in sheet metal processing.
Common models: SUS304 (18-8 stainless steel, non-magnetic), SUS301 (spring stainless steel, slightly magnetic), SUS430 (magnetic, with lower corrosion resistance).
Advantages:
- Outstanding corrosion resistance
- Good machinability and formability
- Food grades are available
- Excellent weldability
Disadvantages:
- High cost
- Fewer finishing options
Material properties:
- Metallic white luster, the surface is not easy to rust, and can be divided according to the surface state: matte surface, bright surface, mirror surface, brushed surface, etc. To protect the surface, a PVC protective film is often attached.
- Generally, no surface treatment is required. If a painted finish is required, additional surface preparation is needed beforehand.
- It is not suitable for electroplating, but electrolysis can be used.
- Suitable for refrigeration, air conditioners, home appliances, and decorative structural parts.
Tensile strength: above 53kgf/mm². Material thickness: 0.1~10.0 mm.
Specific gravity: 7.95 Weight calculation: length (m) × width (m) × thickness (mm) × specific gravity = kilogram (kg) such as:
- SUS304 2.0×1220×2440 weight: 2.0×1.22×2.44×7.95 = 44.65kg
Cold Rolled Steel (SPCC、CRS)
SPCC (Cold Rolled Steel) refers to cold-rolled ordinary carbon structural steel sheet. Cold-rolled steel is the most affordable sheet metal material on the market. In addition, it is the most commonly used metal material for sheet metal processing.
Therefore, it has excellent surface quality and high dimensional accuracy. Coupled with annealing treatment, its mechanical properties and process properties are good. However, it offers little corrosion resistance without a protective finish.
Material properties:
- Iron gray luster, the surface is easy to be scratched and rusted, and care must be taken to protect the surface and maintain an efficient workflow during fabrication.
- It is suitable for electroplating (chromate (color) zinc plating, white zinc plating, nickel plating, tin plating), baking paint, powder coating and other workpieces.
Advantages:
- Excellent surface quality
- Good strength
- Outstanding weldability and dimensional precision
- Low cost
Disadvantages:
- Highly prone to corrosion
- The final finish cost to prevent a part from corrosion is high
- High weight
Hardness: HRB 1/2H = 74～89 1/4H = 65～80 1/8H=50～71 H = 89 or more
Tensile strength: above 28kgf/mm. Material thickness: 0.25~3.2mm.
Specific gravity: 7.85. Weight calculation: length (m) × width (m) × thickness (mm) × specific gravity = kilogram (kg) such as:
The weight of SPCC 2.0×1220×2440 is: 2.0×1.22×2.44×7.85 = 46.74 kg
Aluminium (AL，A1100P，A5052H32P，AL6061T6)
Aluminium Sheet, Aluminium is a silver-white light metal with good thermal conductivity, electrical conductivity and ductility. Pure aluminum has very low strength and cannot be used as a structural material. Aluminum alloy plates are generally used in sheet metal processing.
According to the content of alloy elements, aluminum alloys are classified into eight series: 1000, 2000, 3000 … through 8000 series. Commonly used are 2000 series, 3000 series and 5000 series.
- The 2000 series are copper-aluminum alloys known for their high strength, often referred to as aerospace-grade aluminum. it can be used as various medium-strength parts and components。
- The 3000 series are manganese-aluminum alloys with good corrosion resistance, commonly called rust-resistant aluminum. Anti-rust aluminum;
- 5000 series is a magnesium-aluminum alloy with low density, high tensile strength and high elongation. The weight of aluminum-magnesium alloy is lower than other series under the same area.
Common models: A1100P-O (O stands for soft material, no hardness), A1050P, A5052H32P(good formability, excellent corrosion resistance), AL6061T6, AL6063T5…
Material properties:
- Metallic white luster, the surface is easy to be oxidized and corroded, so the surface is often affixed with PVC protective film.
- Surface treatment: it can be sandblasted, brushed, or polished first, and then anodized (non-conductive, can be dyed in various colors); chromate oxidation (also known as conductive oxidation, with primary color and golden yellow).
Advantages
- Light weight
- High strength-to-weight ratio
- Good corrosion resistance
- Excellent thermal and electrical conductivity
Limitations:
- The high cost
- Poor weldability
Tensile strength: A5052H32P=25kgf/mm² or more, A1100P, A1200P=7 kgf/mm² or more AL6061T6=27kgf/mm² or more
Material thickness: 0.3~20mm.
Specific gravity: 2.75
Weight calculation: length (m) × width (m) × thickness (mm) × specific gravity = kilogram (kg) such as:
- The weight of AL 2.0×1220×2440 is: 2.0×1.22×2.44×2.75 = 16.37kg
Note: Pay attention to the protection of aluminum plate processing, do not scratch the surface, and prevent cracking and die marks during bending. (If the material is too hard, it can be annealed first or use a wider die opening)
Hot-dip Galvanized Steel (SPGC)
GI sheets are CRCA sheets with a zinc coating. Corrosion resistance is improved by zinc coating. There are four different categories of GI sheets: ordinary (O), drawing (D), deep drawing (DD), and extra deep drawing (EDD).
There are numerous zinc plating thicknesses for galvanised steel. sheets that are 120gsm, 200gsm, 300gsm, or 600gsm, for instance. 200gsm refers to a zinc coating of 200 grammes per square metre. Common international grade equivalents include DX51D (EN 10327) and CS/FS/DS grades per ASTM A653.
Material properties:
- Metallic white luster with patterns, the surface is not easy to rust, but white rust spots will occur due to corrosion.
- Galvanized steel typically requires no additional surface treatment.
- Not suitable for electroplating (zinc, nickel, or tin plating).
- It is suitable for refrigeration, air conditioning, heavy motor and roof structural parts.
Advantages:
- Good surface quality
- Good Strength
- Excellent dimensional precision
- Better corrosion resistance
Disadvantages
- Should not be welded
- High weight
- Higher cost than CRCA
Hardness: HRB 1/2H=74～89 1/4H=65～80 1/8H=50～71 H=89 or more
Tensile strength: above 40～55kgf/mm². Material thickness: 0.4~3.2mm.
Specific gravity: 8.25
Weight calculation: length (m) × width (m) × thickness (mm) × specific gravity = kilogram (kg) such as:
The weight of SPGC 2.0×1220×2440 is: 2.0×1.22×2.44×8.25 = 49.1kg
Note: If you want to bend, pay attention to whether the zinc layer on the surface falls off, and regularly clean zinc debris from the lower die after each bend.
Hot Rolling Steel (SPHC、HRS)
Hardness: HRB 1/2H=74～89 1/4H=65～80 1/8H=50～71 H=89 or more
Tensile strength: above 41～52kgf/mm.
Material thickness: 1.4~6.0mm. Material code above 6mm is SS41
Material properties:
- Black-gray luster, the surface is not easy to be scratched, but easy to rust, which must be removed during processing.
- It is not suitable for electroplating (colorful zinc plating, white zinc plating, nickel plating, tin plating…).
- It is suitable for structural parts such as baking paint and powder spraying.
Specific gravity: 7.85.
Weight calculation: length (m) × width (m) × thickness (mm) × specific gravity = kilogram (kg) such as:
The weight of SPHC 2.0×1220×2440 is: 2.0×1.22×2.44×7.85=46.74kg
SPHC1.0×1000×2000 weight is: 1×1×2×7.85=15.7kg
Note:
- If electroplating is to be done, sandblasting or wire drawing must first remove the surface carbonized layer.
Copper (C1020, C1100, C2100, 2200, 2300, 2400, C2600)
Common models: C1020P-O (O stands for soft material, no hardness), C1020P-1/2H (Vickers hardness HV75～120) 1/4H HV=60～100 H HV=80 or more
Tensile strength: O material=20kgf/mm² or more, 1/4H material=22～28 kgf/mm² 1/2H material=25～32kgf/mm², H material=28 kgf/mm² or more
Material thickness: more than 0.3mm
Material properties:
- #1xxx has a copper content of 99.9%, (also known as electrolytic copper or confluence copper) with excellent electrical and thermal conductivity, good drawing processability, good weldability, corrosion resistance, weather resistance, and metallic red luster. Suitable for electrical and chemical industries.
- #2xxx contains 60 to 96% copper, (also known as brass or confluence copper) ductility, processability, and electroplating properties are commonly used in wiring equipment, instrument panels, bullet casings, etc.
- Surface treatment: it can be drawn first, or polished and then pickled, copper-plated, tin-plated, and nickel-plated.
Specific gravity: 8.9
Weight calculation: length (m) × width (m) × thickness (mm) × specific gravity = kilogram (kg) , such as:
C1020P1/4H 2.0×600×1500 Weight: 2.0×0.6×1.5×8.9 = 16kg
C1020P1/2H 1.0×1000×1000 Weight: 1×1××8.9 = 8.9kg
Comparison of Sheet Metal Material
| Properties | Aluminium | Stainless Steel | Cold Rolled Steel | Galvanized Iron / Steel | Aluzinc Steel |
|---|---|---|---|---|---|
| Strength | Low | Very Good | Good | ||
| Weight | Low | High | High | ||
| Corrosion Resistance | High | Very High | Low | Good | |
| Weldability | Good | Very Good | Very Good | Not Recommended | |
| Cost | $$ | $$$ | $ | ||
To summarise, a wide range of sheet metal material grades are available. You can choose the right material based on your part’s functional requirements and budget constraints.
