Stamped Steel Process
Metal stamping uses sheet metal fed into a press with tool and die to rapidly form parts. The process encompasses multiple techniques:
- Stamping/Pressing: Forms sheet metal into parts using tool and die.
- Drawing: Creates deeper parts than stamping alone.
- Bending: Rams push metal against a die to create bends.
- Embossing: Uses roller dies to create raised or sunken designs.
- Notching: Shearing process removing portions of workpieces.
- Punching: Creates holes in sheets.
- Blanking: Cuts larger steel sections into smaller pieces.
- Piercing: Forms holes, slots, or cutouts.
- Lancing: Simultaneously bends and cuts to create tabs or vents.
- Pinch Trimming: Cuts vertical walls by pinching metal between tool dies.
Stamped Steel Applications
- Aerospace: Requires strict quality adherence and precision with real-time adjustability.
- Fluid Power: Uses complex fittings for hydraulic and pneumatic systems.
- Medical: Requires longevity and precision for health-critical equipment.
- Oil and Gas: Depends on safety and quality for hazardous environments.
Does Stamped Steel Rust?
Rust resistance depends on the percentage of alloying elements in the steel. Alloys like chromium and nickel enhance corrosion resistance, making steel nearly rustproof when combined in sufficient quantities.
Cast Steel Process
Steel casting involves pouring molten metal into pre-made molds, allowing it to cool, then removing and finishing parts. Two primary methods are used:
- Investment Cast Steel: Also called lost-wax casting, this method produces highly detailed parts. Patterns assemble within molds, allowing multiple parts per run. Investment casting can produce parts exceeding 1,000 pounds.
- Sand Cast Steel: Uses non-reusable sand molds, a flexible and cost-effective option for metals with high melting points. Sand can be reused for subsequent castings. This method produces parts ranging from a few ounces to several tons.
Cast Steel Applications
- Turbine Engine Manufacturers: Produce fuel system components and hardware through investment casting.
- Defense Sector: Requires high-temperature, durable parts for weapons and propulsion systems.
- Mining: Uses wear-resistant and heat-resistant components.
- Railway Industry: Produces wheels, braces, and assemblies.
Cast Steel and Brittleness
A material is considered brittle if it breaks without significant plastic deformation and little elastic deformation. Cast steel excels at withstanding sudden impact without deforming or breaking, effectively combining ductility and strength.
Strengths and Weaknesses
| Factor | Stamped Steel | Cast Steel |
|---|---|---|
| Die cost | Affordable and long-lasting | Expensive; must withstand high temperatures |
| Production speed | Faster; highly automatable | Slower for investment and sand casting |
| Per-unit cost | Lower for simple parts | Competitive for complex parts |
| Design flexibility | Limited shape and thickness flexibility | Greater freedom for intricate designs |
| Tolerance control | Less tolerance control | Better tolerance control |
| Surface finish | Can require additional processing | Excellent finishes achievable |
| Internal features | Cannot create blind holes easily | Ability to create blind holes |
| Material waste | Scrap from unused cut pieces | Reusable sand reduces waste |
| Tooling time | Long pre-production tooling time | Molds must be remade each run |
Why Lubricant is Used in Metal Stamping
Stamping generates significant friction and heat as dies continually form metal sheets. Friction causes excessive wear and scratches to the tool and die surface, creating two cost problems: machine downtime for part replacement and the replacement costs themselves. Lubrication helps surfaces glide smoothly, preventing wrinkles, rips, and tears while protecting tool integrity.
