Efficient material usage
Powder is pressed to shape rather than cut away. Callo lists “poor use of material” as the trade-off of cutting machining — sintering is the answer to it.
The method
Why powder metallurgy?
Metal powder is pressed into a tool and heated until the particles bond. Nothing is cut away, the shape comes from the tool rather than from a cutter path, and features that are expensive by every other method are close to free.
01Advantages
Six reasons a purchasing manager should care.
Repeatable production
The tool defines the part. Once the die is right, part number ten thousand is the same as part number ten.
Complex geometries
Transverse grooves and channels, odd contours and integrated features come out of the tool — contour costs tooling, not part price.
Reduced machining
Net shape out of the furnace. Finishing is applied where the tolerance class genuinely needs it, not everywhere.
Integrated functions
Self-lubrication, filtration, magnetic flux paths and mechanical structure can live in one pressed component.
Volume economics
Low or modest tooling cost to start, and a fast per-part process — the cost curve improves as the volume grows.
02Comparison
Sinter steel versus everything else.
Callo publishes the trade-offs alongside the advantages, which is unusual and worth keeping. Sintering is not the answer to every part — knowing where it loses is what makes the recommendation trustworthy when it wins.
Sinter steel vs. Cutting machining
Sintering wins on
- No or modest tool costs i.e. low start-up costs
- Plenty of freedom to make changes
Trade-offs
- Labour-intensive
- Poor use of material
Sinter steel vs. Forging
Sintering wins on
- Good material characteristics
Trade-offs
- More limited geometry
- Poorer tolerances ±0,3 calibrated
- Often requires finishing
Sinter steel vs. Stamping
Sintering wins on
- Faster process
Trade-offs
- Limitations in geometry / tolerances
Sinter steel vs. Precision casting
Sintering wins on
- Copes with transverse grooves and channels
Trade-offs
- Tolerances and material characteristics
Sinter steel vs. Cold forming
Sintering wins on
- Fast process, comparable to sinter
- Copes with thin-walled geometries
Trade-offs
- More limited geometry
- Phosphatising of workpiece
Sinter steel vs. Die casting, Al and Zn
Sintering wins on
- Fast process
- Good tolerances
Trade-offs
- Weak material
- Costly tools
Comparison content reproduced from Callo’s published technical material. Nothing has been added.
03Material
Where sinter sits on the scale.
In Callo’s own words, sintered material does “just above die casted Zn to almost as good as forged”. Where on that range a given part lands is decided by density — which is decided by geometry, which is decided early.
Die-cast Zn
Sinter, low density
Sinter, high density
Forged
Qualitative scale based on Callo’s published statement. No numeric material values are implied — ask for data against your specific density target.
- 01
Idea or drawing
A print, a 3D model, or a part that already exists and needs to be made better or cheaper. The earlier this arrives, the more Callo can influence.
- 02
Material & design
Density target, material characteristics, geometry and function are fixed together. Density drives strength, hardness, elasticity and impact resistance.
- 03
Tooling
Die, punches and core rods are designed around the pressing direction. Complex contours cost nothing extra on the part — only on the tool.
- 04
Compaction
Metal powder is pressed to net shape. Callo runs a powder press built in-house for multi-level structural parts.
- 05
Sintering
The green part is sintered so the particles bond. Callo built its own pusher furnace into the production line.
- 06
Finishing
Repressing, cutting-machining, roll polishing, oil impregnation — whatever the tolerance class and function require.
- 07
Quality control
Inspection against the drawing inside an ISO 9001 quality system, certified since 2004.
- 08
Serial production
Repeat production with short lead times — Callo’s stated focus alongside staying at the technical front of PM.
04Custom components
Have a component in mind?
Send Callo your drawing or your requirements and start a technical discussion. The earlier the conversation starts, the more there is to gain — geometry, material, tooling and production economics are still open.
- 01
Send what you have
Share the available part information directly with Callo and confirm the preferred drawing or model format.
- 02
Talk to someone technical
Callo publishes direct phone and email contacts for questions and orders.
- 03
Get a real answer
Discuss feasibility, materials and tooling requirements with Callo before production.
Demo page only — file formats and delivery workflow require Callo approval