Powdered Metal Structural Parts
At Atlas Pressed Metals, we manufacture precision sintered metal structural components from small volume needs to very large demands. The pressed metal process is ideal for small structural components with complex geometries and tight tolerances. Our state-of-the-art metallurgical capabilities, combined with our highly educated and experienced metallurgical staff, ensure finished products to your exact specifications. Atlas can also discuss converting your component from other metal-forming technologies to powdered metal manufacturing.
Our experienced team possesses years of industry knowledge and is ready to assist with sintered metal component product development, design, and material selections. Atlas will optimize multi-level designs with tight tolerances, minimizing secondary operations required to manufacture the finished product.
Benefits of Manufacturing Structural Components Using the Powder Metal/Sintered Process
What is a Structural Component?
In powder metallurgy, a structural component describes a part or component that is intended to carry and withstand mechanical loads and stresses within a larger structure or assembly. A structural component is designed to provide strength, rigidity and support to the overall finished structure or assembly.
Structural powder metal components derive their strength from the selection of the appropriate metal power (and resulting microstructure) combined with compaction and sintering strategies. Strength results in improved tensile and yield strength and hardness.
Utilizing powder metallurgy for structural component manufacturing provides many additional benefits, including tight tolerances, dimensional accuracy, consistency, and the capacity for all production volume requirements. A key benefit of using powdered metal for sintered metal components is its cost-effectiveness due to its high material utilization. The ability to produce structural components to tight tolerances also eliminates or reduces the need for additional operations, often resulting in both production time and cost savings.
With little to no waste, powdered metal is a green process due to its low energy usage and minimal scrap, making it more economical than standard machining, casting, or most other metal-forming technologies. Material selection for small structural components allows for the optimization of the component’s performance for its intended application with little variation in the manufacturing process.
At Atlas Pressed Metals, our team deeply understands more than just sintered metal component manufacturing. We also provide a high level of expertise in engineering and the material science surrounding powdered metallurgy. This means that we can recommend metal powders that help our customers in designing small metal components that will optimize performance. When a properly selected material is combined with appropriate process parameters, the result is a finished structural component that meets the application requirements with proven cost-savings over other metal forming choices. This method is ideally suited for high-volume applications because geometries formed by the die show little to no variation.
Additional benefits to using powdered metallurgy for structural components include the following:
- Lower tool cost
- Consistent reproducibility
- Tight tolerances as compared to castings and stampings
- Cost-effective as a manufacturing process
- Ability to accommodate low to high volume (5000 to 5M+ annual volume)
- In addition, the design features of powdered metallurgy eliminate the need for draft angles and sheer, which would be necessary for a casting or stamping design.
Applications for Structural Components
- Control levers
- Hinge components
- Electric Motor
- Motor Cores
- Pump rotors and vanes
- Pump Rings
- Simple and structural spacers
Utilizing powdered metallurgy for manufacturing structural components has various benefits for industries requiring consistency and quality metrics for optimal performance.
Materials Used for Manufacturing Structural Components
The powder metallurgy process begins with a collection of metal powder particles.
Metal powders are engineered materials that meet a wide range of performance requirements. Understanding the powder is crucial in powder metallurgy as this is the key input to the production of a final metal component.
The powder is produced through either solid-state reduction, atomization (gas, water, or centrifugal), electrolysis, or chemical treatments of the metallic material.
Atomization is the typical method used today. It involves the conversion of molten metal in a spray of droplets that solidify into powder. Water atomization is the most common form of atomization as it results in irregularly shaped particles, which is beneficial in the compaction of powder metal component production.
Metal powders are classified as elemental, partially-alloyed, or pre-alloyed. Elemental powder is a granular form of pure metal powder. They are the building blocks of creating alloys and composite materials. Partially-alloyed powders are a mixture of elemental powders of different materials blended together, and a prealloyed material is in an alloyed state as produced by atomizing a combination of metals.
In most cases, the powder mixture, whether elemental or prealloyed, also contains additives (lubricants or binders) for increased tool life, to assist in the ejection of the component from the compaction die or to hold the metal part together before the sintering process. These additives are removed from the component desiring the sintering process.
The geometry of the individual powder is defined by particle shape and internal structure, particle size and distribution, and surface area. Particles come in a variety of shapes, from spherical, irregular, flake, dendritic, and sponge. The distribution of particle sizes in the powder influences compaction as smaller particles will fill in the void between larger particles. This combination of sizes improves compaction density and material properties.
These are critical parameters in powder metallurgy as they determine how the powder performs when filling the die, during compaction, and in sintering. These factors must be optimized to achieve the desired strength and density in the green stage and in the final sintered component.
Powder Materials For Structural Applications
Iron powder is the most commonly used material for structural applications. It can be used alone but is often combined with other alloying materials to improve mechanical properties. Common additives are carbon, copper, nickel, and molybdenum.
Carbon steel is made from a mixture of iron and graphite powders. During the sintering process, the graphite is absorbed in the iron to produce a steel structure. Prealloyed carbon steel is also available for the appropriate application.
Copper steel is produced by adding copper powder to iron powder. The result is an improvement in strength and hardness.
Nickel steel added to the iron powder (with or without copper powder) results in high strength components with favorable fatigue strength.
Other additions to the iron powder may include infiltration of lower melting materials such as copper to increase density and enhance impact resistance. The addition of a small amount of phosphorous is used to increase electromagnetic properties as well as provide ductility and strength.
Low alloy steels and diffusion-alloyed steels are made from prealloyed steel powders using nickel, molybdenum, and manganese. This mix is used when the structural component requires high performance and high hardenability.
Electromagnetic materials are used when the component requires good permeability, purity, and density.
Stainless steel powder metals are required when the component and or application requires significant mechanical properties and high corrosion resistance.
Copper base materials include pure copper, brass, bronze, and nickel silver. Each of these powders is selected for its particular characteristics, such as electrical or thermal conductivity, oil impregnation, machinability, ductility, or corrosion resistance.
Aluminum powders offer good corrosion resistance, excellent finishing properties, high strength- and rigidity–to–weight ratios, and vibration and sound-damping features.
Atlas ships nearly 75 million structural components each year to a variety of industries and applications!
Understanding Powder Metallurgy
Step One: Collaborative review of your new part design or an evaluation of a potential conversion to powder metal for an existing part
Step Two: Selecting the best powder or powder blend for durability, reliability, and accuracy
Step Three: Compacting the metal powder to precise specifications under controlled pressure
Step Four: Heating or "Sintering" to create a permanent form
125 Tom Mix Dr.
P.O. Box P
DuBois, PA 15801
“We have found Atlas Pressed Metals to be a solid organization that has a genuine commitment to the success of their customers. They have provided us with a great quality product and excellent service.”