Powdered Steel & Full Density Powdered Metal
Quick Full Density Steel Powder Metal Links
- What is Full Density Steel Powdered Metal
- Full Density Powdered Metal Benefits
- Full Density Powdered Metal Process
What is Full Density Steel Powder Metal?
Full Density Powdered Steel Metallurgy combines the high volume processing of powder metal compaction with the physical properties of cast or wrought materials. Full Density provides the ultimate physical properties for conventionally compacted PM materials. Full Density Powder Metallurgy combines the high volume processing of powder metal compaction with the physical properties of cast or wrought materials. Full Density provides the ultimate physical properties for conventionally compacted PM materials.
Full Density Powder Metal Benefits
Full Density Powdered Metal offers significant benefits when compared to conventional powder metal processes. Typically achieving 97% to 99%+ of theoretical densities, these components are equivalent to most castings and approach wrought product properties. They provide strength, ductility, and corrosion and wear resistance that are unmatched in the Powdered Metal industry.
Design Benefits of Full Density Powder Metal:
- Improved Strength Ultimet 16, the Full Density equivalent to 316L, possesses slightly higher tensile strengths than CF 8M (Cast 316), and 25% to 40% higher tensile strengths than equivalent PM alloys
- Excellent Ductility Superior to cold rolled 316L, Ultimet 16 matches Cast 316's outstanding ductility; The ductility of Full Density stainless steel is 25% higher than its closest conventional PM counterpart
- Superior Corrosion Resistance Approaching corrosion rates of wrought 316L, Ultimet 16 will survive environments that will significantly deteriorate conventional PM stainless steel
- Outstanding Wear Resistance The homogenous network of complex carbides created in Full Density tool steels provides an outstanding wear surface
- Superior Machinability Full Density tool steels provide a more uniform material for machining, including milling, drilling, turning and grinding, due to the lack of imperfections such as carbide banding, oxide inclusions, and sulfide stringers typically found in wrought or cast tool steels
- Reduced Assemblies Full Density may use liquid phase sintering to combine several parts into a single, more complex, component
Full Density Powder Metal Process
While conventional Powdered Metal processing sinters parts to 82%-88% of the theoretical density, Full Density materials are carefully processed to achieve densities ranging from 97.5%-99.7% of theoretical density.
Since material properties such as elongation and yield strength are closely related to density, Full Density materials possess significantly better properties.
Full Density powdered metal components are sintered in closely calibrated, high temperature vacuum furnaces using our proprietary liquid phase sintering technology. Controlling the chemistry of the Full Density alloys also dictates the small percentage of material that becomes liquid at the sintering temperature.
This liquid rapidly diffuses throughout the entire compact, closing the pores and achieving the desired densification.
High purity metal powders and additives are selected to provide unique physical properties tailored to the customer's requirements. The powders are blended with lubricants which aid powder flow, green density, and green strength. Mixing metal powders in the solid state provides opportunities to engineer a variety of material properties unique to PM.
Powder metal flows from the feedshoe into the die cavity where multiple punches compress it to half its original volume. Intense compacting forces first realign, then deform the metal particles, creating localized mechanical bonds, forming a 'green' part. Green parts are ejected and mechanically conveyed to minimize handling damage.
The initial sintering stage removes binders and lubricants and cleans the surface of the metal particles, ensuring excellent mechanical properties in the finished component. Time at temperature provides the energy that transforms the mechanical bonds into metallurgical bonds. Liquid Phase Sintering specific alloys creates components which attain 97.5% to 99.7% of the alloy's theoretical density.
One benefit of powdered metal is its net shape capability—often providing a finished component after the sintering operation. Sizing or coining operations are used for more demanding dimensional requirements. The homogeneity of Powdered Metal materials lends itself to a variety of machining applications, including grinding, turning, milling, tapping, etc. Oil impregnation utilizes PM's porous pathways as a built in lubrication reservoir. Other surface treatments are also available to achieve specific requirements.