The material of a part determines how it behaves during use: how well it maintains its dimensions, how it responds to load, how much it wears, how accurately it can be manufactured, and how long it can operate reliably. This is why material selection is one of the most important decisions in custom and small-batch part manufacturing.
A good decision is based on handling the operating environment, load, manufacturing technology and cost as one connected system.
The role of material selection in part reliability
Material selection has a direct impact on the service life and operating behaviour of a part. A shaft, bushing, support element, guide element or housing part all require different material properties. This is why different criteria come into focus during material selection, such as:
- For loaded machine parts: strength, rigidity and resistance to fatigue.
- For sliding or wear elements: friction properties, wear resistance and lubrication conditions.
- In food industry, chemical industry or outdoor environments: corrosion resistance, cleanability and resistance to environmental effects.
A reliable part is not necessarily made from the strongest material, but from the one that fits the application well from both an engineering and manufacturing perspective.
What operating conditions will the part be exposed to?
Before selecting the material, it is worth clarifying the operating environment precisely. A rarely moved support element, a continuously rotating shaft, a bracket exposed to vibration or an intensively wearing bushing all require different materials.
In custom part manufacturing, material selection is based on load, wear, corrosion effects, temperature and the installation environment. The right material grade and the appropriate manufacturing technology together create a functional solution: a different material may be justified for a wearing bushing, a precisely fitting machine element, an outdoor part or a structural element exposed to higher loads.
If a previous part has broken, worn or deformed, the type of failure can provide valuable information for selecting the right material grade and technology.
How does the material affect manufacturability?
The material selected for a part also affects the manufacturing process. Its machinability, thermal conductivity, hardness and dimensional stability influence machining time, tool wear, surface quality and the tolerances that can be maintained.
Different properties become important in CNC milling, CNC turning, grinding or wire EDM. A material is a good choice when it can be manufactured cost-effectively together with the geometry, tolerances and production quantity of the part.
This is especially important for custom and small-batch parts, where production planning, workholding, operation sequence and material grade together determine the final result.
Metal or engineering plastic? The decision should be based on the application environment
When selecting a material, it is worth starting from the function, load and operating environment of the part. For both metals and engineering plastics, there may be several suitable solutions, but the optimal choice always depends on the specific application.
Metal parts
Metals usually come into focus when a part has to withstand higher mechanical loads, wear, heat effects or precise fits. In these cases, the material grade is selected based on load conditions, the operating environment and manufacturability.
- Steel: for higher mechanical loads, rigidity or wear resistance.
- Stainless steel: for corrosive, wet or hygiene-critical environments.
- Aluminium: for lower weight, good machinability and a favourable strength-to-weight ratio.
- Bronze and copper alloys: for sliding and wear applications, for example bushings or guide elements.
Engineering plastics
Engineering plastics can provide a good solution in many mechanical applications, especially when favourable friction properties, lower weight, corrosion-free operation or noise reduction are required. When selecting the material, temperature, mechanical and dimensional accuracy requirements should also be clarified, as different materials are suitable for different applications.
- POM: a precise material with good dimensional stability and favourable friction properties.
- PA: for higher mechanical loads and good wear resistance.
- PE: for favourable sliding properties, impact resistance or corrosion-free operation.
- PTFE: for low friction and chemical resistance.
- PEEK: for higher operating temperatures, higher loads or increased wear resistance.
How does material selection affect the total cost of a part?
The cost-effectiveness of a part is determined by the price of the raw material, machinability, manufacturing time, post-machining, scrap risk and service life together.
A material that is easier to machine may reduce manufacturing time. A more wear-resistant or corrosion-resistant material may provide a longer service life. For critical parts, the cost of machine downtime is also part of the decision, so the best choice is often the one that delivers favourable engineering and economic results over the full service life of the part.
What should be provided when requesting a quote?
When requesting a quote, a technical drawing, 3D model or sample part can be very helpful. It is worth providing the function of the part, the installation environment, the expected load, the production quantity, the required accuracy and the known material grade.
If there has been previous wear, breakage, deformation or fitting problem, it should also be indicated. This information helps ensure that material selection is considered together with the manufacturing technology, so the finished part can operate reliably in its own operating environment.
We help you select the right material for your part
Before requesting a quote, send us your technical drawing, 3D model or sample part. Based on our experience, we recommend the right material grade for the part, taking into account its function, load, operating environment and manufacturability. Contact us.