Materials & surface finishes.
A practical guide to the material and finishing details that help turn your drawing into a clear manufacturing brief.
Specify the material your part needs.
A material family is a starting point, not a complete specification. A useful RFQ identifies the grade, condition, required documentation and the environment in which the part will work.
The examples below are discussion starting points. Material availability and the accepted manufacturing route are confirmed for each project.
| Material family | What to clarify |
|---|---|
| Aluminum for CNC | Examples for discussion include 6061 and 7075. State the temper, appearance and surface-treatment requirements. |
| Stainless steel for CNC | Identify the grade and condition. Include corrosion environment, strength and finishing requirements. |
| Brass for turned components | State the alloy and any composition restrictions, especially for regulated or contact applications. |
| Stainless steel for MIM | 316L and 17-4PH are common discussion points. The sintered or heat-treated condition and acceptance data must be project-specific. |
Finishing changes the acceptance requirements.
A drawing should distinguish machined dimensions from dimensions that apply after anodizing, plating, heat treatment or another operation. Identify masked surfaces, functional contacts and cosmetic faces.
If color or appearance is important, define the acceptance method. A screen image or a general color name may not be enough to establish a repeatable cosmetic standard.
- As-machined condition and permitted tool marks
- Anodizing or coating requirements for aluminum
- Passivation, polishing or plating where specified
- Heat treatment or other post-processing requirements
- Marking, cleanliness and packaging instructions
Ask for the right documentation.
Request certificates, traceability and inspection records that the project actually requires. Their scope and availability need confirmation before you accept the quotation.
For MIM, a generic wrought-material data sheet does not define the properties of a sintered component. Specify the required properties and test basis with the manufacturing specialists.
Before the quotation.
Can you help if the material is not selected?
Describe the operating environment, loads, weight, appearance and cost constraints. Options can then be discussed with the appropriate manufacturing specialists; final selection remains part of the agreed project specification.
Does a material name guarantee a particular strength?
Properties depend on the grade, condition and manufacturing route. State the required condition and performance rather than relying on the alloy name alone.
Should I specify dimensions before or after coating?
Identify which functional dimensions must meet the drawing after finishing. Coating and other treatments can affect fits, threads and contact surfaces.
Ready to review your part?
Share the drawing, material, quantity and the questions you need to resolve.