In sintering, metal powders are formed into solid parts under heat and pressure without fully melting the material. In contrast, casting involves pouring liquid metals into molds. Sintering allows for more precise control of material composition and microstructure.
Certain geometries and shapes are difficult or unfeasible in the sintering process. These include grooves, undercuts, threads, knurlings, transverse passages to the pressing axis, and spherical closures without mechanical post-processing.
When designing sintered parts, the following points should be considered: Lateral dimensions (wall thicknesses) should be greater than 1 mm, the lateral dimensions of different part areas should be at least 1/6 of their respective heights, sharp edges and angular transitions as well as formations should be avoided.
Materials that can be sintered are mainly based on iron, copper, or aluminum. By mixing various metals and plastics, the properties of the materials can be adapted to the specific requirements.
Typical applications for sintered parts include self-lubricating bearings, silencers, sieves, gears and transmission components, spacers, hubs, brake pads, heat exchangers, and implants.
The cost of a sintering tool varies depending on the complexity, size, and use of the part and can range from €10,000 to over €100,000.
Sintering makes sense when the piece numbers over the lifetime of the part are high. However, this depends on size, shape, and alternative manufacturing technologies, so “high” can vary greatly. A cost comparison between sintering and CNC manufacturing can be insightful here.
Common post-processing methods for sintered parts include grinding, polishing, calibrating, and sometimes heat treatments to achieve the desired surface qualities and mechanical properties.
The corrosion resistance of sintered parts strongly depends on the material composition and density. In general, sintered parts can have good corrosion resistance through appropriate material selection and post-treatments.
All powder metal steels are fundamentally weldable.
The achievable tolerances depend on the size and direction of the part. They vary according to diameter, height, flatness, parallelism, and 90° angle. The exact values can vary depending on the material, sintering temperature, and time.
Yes, more accurate tolerances can be achieved through calibration and/or post-processing. Our parts can achieve accuracy up to 4µm, but at such small tolerances, measurability becomes a consideration.
Yes, sintered shaped parts can be both sinter-hardened and case-hardened.
The particle size of the powder has a significant impact on the properties of the final product. Finer powders lead to higher density and better mechanical properties but also require higher sintering temperatures and pressures.
FAQs - Sinter Steel vs. Full Steel
The tensile strength of full steel varies depending on the alloy and heat treatment, ranging from 400 MPa to over 1,500 MPa. High-strength steels can even reach values from 800 MPa to over 2,000 MPa. Sinter steel, on the other hand, typically has a lower tensile strength, ranging from 200 MPa to about 800 MPa. These values can vary depending on the density and porosity of the sinter steel.
The elongation at break for full steel generally lies between 10% and 40%, depending on the alloy and heat treatment. High-strength steels used in critical applications such as aerospace components often have a lower elongation at break, typically in the range of 5% to 15%. For sinter steel, the elongation at break is usually lower, ranging from 1% to 10%. The porous structure of sinter steel leads to less deformation before breaking.
The yield strength of full steel can range from 250 MPa to over 1,000 MPa, depending on the alloy and heat treatment. High-strength steels can have yield strengths from 700 MPa to over 2,000 MPa. Sinter steel typically has a lower yield strength, ranging from 100 MPa to about 600 MPa. The porous structure of sinter steel leads to earlier plastic deformation.
FAQs - Powder Metallurgy
Powder metallurgy offers numerous advantages, including the ability to produce complex shapes with high precision and minimal post-processing. It is particularly efficient in terms of material consumption and allows for the production of parts with controlled porosity, which is important for specific applications such as self-lubricating bearings or filters.
Yes, powder metallurgy is well-suited for the production of lightweight materials, as it allows for the creation of porous structures that are lighter without losing strength.
Powder metallurgy enables the production of complex shapes with high precision and minimal post-processing. It is cost-efficient as it minimizes material waste and allows for the production of parts with controlled porosity for specific applications.
The density of sinter steel can be increased through additional compaction processes such as repressing or hot pressing. Theoretically, sinter steel can be compacted up to the density of pure iron, but this requires special processes and can affect the material’s properties.
|Size (direction) mm
|Diameter (horizontal) µm
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In addition to nickel plating, there are various methods to treat the surface of sinter materials. These include plating, tempering, vibratory finishing, nitriding, passivation, and coating. Each of these methods has specific advantages and can be used depending on the requirements of the component.
Epilamizing is a process where a thin layer of a suitable material is applied to sintered components. This improves surface properties, such as wear resistance and corrosion resistance. The choice of material depends on the specific requirements of the component.
Yes, powder metallurgy is suitable for the production of composite materials. Different materials can be mixed and sintered together to achieve the desired properties.