Metal stamping is important in manufacturing. It transforms sheet or strip metal into shapes and structures by applying pressure. This technique produces complex parts with high precision. It is vital in industries like automotive, aerospace, electronics, and consumer goods.
Yonglihao Machinery specializes in metal stamping services. We provide high-quality, precise stamped parts to meet our customers’ diverse needs. Our expertise combined with advanced technology ensures optimal performance and durability for a variety of applications.
In the following pages, we take you deeper into metal stamping design basics. We explore methods for making strong and light-stamped parts. We also discuss tolerances and surface finishes. And, we give insights into designing complex stamped parts.
What is Metal Stamping?
Generally speaking, stamping is the process of manufacturing metal parts, products, and prototyping. As society grows, so does the demand for metal parts in a variety of industries. As a result, manufacturing methods have had to become faster and more efficient to keep up with the demand. In this case, metal stamping has become a great way to process flat metal parts into standardized parts.
How Does Metal Stamping Work?
Stamping can also be referred to as pressing. It is usually a process in which a flat piece of metal is put into a press to stamp a specific shape. For stamping, the press is the source of power. When the sheet metal is pressed between molds, a specific part is formed.
For professionals, CAD/CAM technology is used to design the tooling before the metal is manufactured. Most importantly, these designs must be accurate. It is also important to remember that the same 3D model of a tool may have hundreds of different parts. As a result, some parts of the planning process can take a long time.
Types of Metal Stamping
There are four main types of metal stamping processes:
Progressive Die Stamping
This stamping process usually has several stations, each with a different function. The metal first passes through the press before it passes through the die press. At this stage, each station performs its own cutting, punching, or bending work.
Since the work of each station is based on the work of the previous station. Therefore, the metal needs to pass through all the stations to form a complete part. In addition, this metal stamping process is ideal for manufacturing metal parts with complex geometric requirements. They can help manufacturers to reduce production costs and shorten turnaround time.
Deep-drawing Stamping
For deep-drawing stamping, a blank sheet of metal must be drawn into the press by means of a punch. In this way, the sheet metal is shaped to meet the manufacturer’s needs. The name of this method derives from the fact that the depth of the stamped sheet is greater than its width.
Deep drawing stamping is more effective and less costly than turning, which requires more raw material. Deep drawing stamping is commonly used in the manufacture of electronic relays, cookware and utensils, aircraft parts, and automotive parts.
Four-slide Stamping
Four-slide stamping has many advantages over the conventional stamping process. Since there are four slides, four different tools can be used for bending at the same time. When the material is placed into the four slides, each axis bends the material.
This is considered to be the ideal method of stamping. This is because it works very well and can be used in many situations. If the process can be executed correctly, it can produce many complex things. It is also quite a flexible option for metal parts that require frequent design changes.
Short Run Stamping
This method is perfect for companies that want to minimize the cost of the tools they need right from the start. Small projects or prototypes can be easily created using this metal stamping process. Manufacturers begin by making blanks. Then, using a mix of tooling components and dies, they stamp, bend, or drill the metal parts.
Due to the smaller production scale and the fact that the forming operation can be customized. The unit cost of this stamping process is therefore much higher. However, the low cost of the molds makes up for this. Therefore, this process is very cost-effective for projects that need to be completed quickly.
Metal Stamping Design Basics
In metal stamping design, choosing the right material is critical. However, quality materials alone are not enough to ensure the quality and performance of the final product. It needs to be combined with good mold design and proper machining. These create a high-quality part that meets the requirements.
Material Selection
In metal stamping design, choosing the right material is critical. Common materials include steel, aluminum, and brass. Steel has high strength and good durability for parts that require high strength and wear resistance. However, steel is less ductile and more difficult to machine. Aluminum is lightweight and ductile. This makes it good for lightweight parts. But, its strength is low and needs alloying to improve. Brass has excellent electrical conductivity and corrosion resistance. It is suitable for electrical components and decorative items.
Tooling Design
Efficient die design is critical to the success of metal stamping. Die design needs to consider factors such as aperture size, edge distance, and bending radius. The hole diameter should be at least 1.2 times the thickness of the material to prevent deformation or breakage of the material. Small edge distances may make material tear during stamping. They should be at least twice the material thickness. The bending radius’s design must consider the material’s thickness and ductility. It’s generally recommended that the bending radius be at least twice the material’s thickness. Accurate mold design can avoid distortion and ensure consistent and high-quality parts.
Common Processes
Metal stamping processes include blanking, bending, piercing, and forming. Each process has a significant impact on the final shape and performance of the part, so it is important to distinguish between them.
- Piercing: Piercing is also known as stamping. It is a process in which holes are punched in a sheet or piece of metal for cutting by using a punch and die. In this process, the useless part of the metal object is cut off and turned into scrap.
- Blanking: Blanking is also a manufacturing process in which parts are made by punching holes in a sheet or strip of metal and then punching them out. However, unlike piercing, the punched-out part is used as a new piece of metal.
- Bending: When bending metal, only the shape of the metal is changed. In addition, the length and width of the sheet metal remain the same before and after bending.
- Forming: In the forming process, the metal is bent several times to form complex shapes. This is a cost-effective method of manufacturing metal parts without changing the thickness of the material.
Designing High-Strength and Lightweight Stamped Parts
Material Optimization
Material optimization is critical when designing high-strength and lightweight stamped parts. Strong steels and alloys are key for this. They are especially important for cars and planes. These materials not only provide excellent strength and durability but can also significantly reduce part weight. High-strength steel is a type of steel. They include ultra-high-strength steels (UHSS) and dual-phase steels (DP steels). They have great strength-to-weight ratios. This makes them ideal for car parts. Aluminum alloys and titanium alloys are widely used in aerospace parts manufacturing due to their lightweight properties and high strength.
Structural Design
Picking the right material is important. But, so is optimizing the part’s shape. This is key to making a strong and light design. Below are a few common structural design techniques:
- Rib design: Adding ribs to a part’s interior can greatly increase its strength and rigidity. This comes without adding much weight. Rib design is common in cars and planes. It’s used in parts like door interiors and wing structures. These parts need the strength and support that ribs provide.
- Strategic Thinning: By thinning in areas of low stress, the weight of a part can be reduced while maintaining the necessary strength. For example, car chassis and frame parts use this technique. They use it to cut material use and reduce weight.
- Hollow Construction: The use of hollow construction can further reduce weight while maintaining high strength. For example, hollow axles and beams not only reduce vehicle weight but also improve fuel efficiency and handling.
- Optimized Geometries: CAD and FEA can optimize part shapes. They disperse stress and cut the risk of fatigue and fracture. These techniques are vital in aerospace and automotive. They ensure the safety and reliability of parts in extreme conditions.
Tolerances and Surface Treatments
Tolerance Design
In metal stamping, accurate tolerance design is critical to ensure part fit and function. Tolerance is the allowable range of size variation. It affects how parts fit together. Common tolerance standards include ISO 2768 and DIN 16901, which contain tolerance ranges and application conditions for various dimensions. Tight tolerance control can be achieved through proper mold design and material selection. High-precision CNC machines reduce deviations. They are used for mold machining. High-quality, even materials also help. They can greatly cut deviations. This ensures consistent, high-quality parts.
Surface Treatments
Surface treatments play an important role in improving the corrosion and abrasion resistance as well as the aesthetics of metal stamped parts. The following are a few common surface treatments:
- Electroplating: Plating a thin layer of metal, such as nickel, chromium, or zinc, onto a metal surface can greatly improve a part’s resistance to corrosion and wear. Commonly galvanized steel is often used in automotive body structures to prevent rusting.
- Anodizing: It is used primarily on aluminum and its alloys. The process makes an oxide film on the metal’s surface. This film increases its hardness and corrosion resistance. The surface of anodized aluminum products can also be dyed to improve the look. This is common in electronic shells.
- Powder Coating: Powder coatings are applied to metal surfaces by electrostatic spraying and then cured by heat to form a hard protective film. Powder coating has great corrosion and abrasion resistance. It lacks harmful VOCs, making it environmentally friendly. It’s a common surface treatment for appliances and furniture.
Designing Complex Shaped Stamped Parts
Complex Shapes
Making complex shaped stamped parts, like deep draws and curves, has many challenges. Deep drawing requires turning flat metal into 3D shapes with depth. This process can thin and fracture the metal. To fix these issues, Yonglihao Machinery recommends paying special attention to picking materials and designing tools. Using materials with high ductility and good formability, like aluminum and some high-strength steel, can reduce the risk of cracking. Also, the mold design should consider progressive deformation. This would reduce the amount of deformation at each step. It would avoid stress concentrations and cracking.
For complex curves, accurate tooling and press control is critical. Complex curve design requires highly accurate molds and advanced stamping equipment to ensure accurate and consistent curves. CAD and CAM technologies help. They optimize die design and machining to improve product accuracy and quality.
Advanced Techniques
Advanced Die Stamping and Transfer Die Stamping are common techniques used to cope with the demands of complex geometries and high production volumes.
- Progressive Die Stamping: This technique uses a series of dies, each performing a different stamping operation. Complex shapes and high-precision parts can be realized through the multi-step process. Progressive Die Stamping is for high-volume production. It creates many consistent parts quickly, which boosts productivity.
- Transfer Die Stamping: In this process, a strip of material is passed through multiple dies. Each die does a different stamping operation on the material. Unlike progressive die stamping, each step of the transfer die stamping operation is performed in a different location, making it possible to handle very complex parts. Transfer die stamping is particularly well suited to the production of parts that require high precision and complex shapes, such as automotive and aerospace components.
Conclusion
In metal stamping design, picking the right materials is key. You also need to design precise molds and pick good surface treatments. These steps are essential for making high-quality, durable parts. Steel, aluminum, and brass each have unique advantages and challenges. These factors influence the final product’s performance. Accurate tolerance design is critical. So are advanced techniques like progressive and transfer die stamping. They are needed for making complex shapes and keeping product consistency.
By following these guidelines, manufacturers can ensure their stamped parts meet the highest standards. For expert metal stamping services, contact Yonglihao Machinery. Our expertise ensures optimal solutions for your manufacturing needs.
FAQ
What are the common materials used in metal stamping and their pros and cons?
Steel is strong and cost-effective but heavy and prone to rust. Aluminum is lightweight and corrosion-resistant but less strong and more expensive. Brass offers good corrosion resistance and aesthetics but is costlier and weaker compared to steel and aluminum.
How to choose the right surface treatment for stamped parts?
Choose surface treatments based on environmental exposure, durability, and aesthetics. Electroplating enhances corrosion and wear resistance. Anodizing is best for aluminum, adding corrosion resistance and color. Powder coating provides a durable, aesthetic finish suitable for various applications.
What are some environmentally friendly practices in metal stamping design?
Use recyclable materials like aluminum and steel, optimize designs to minimize waste, and employ eco-friendly surface treatments such as water-based or low-VOC coatings to reduce environmental impact.