Overview of cemented carbide production
The sinter HIP procedure is the key to unlocking our cemented carbide material’s specific properties. The cemented carbide blanks can then only be processed further using diamond grinding discs or wire-cut and die-sinking erosion machines.
We therefore rely on our own in-house grinding systems to produce a tool that is ready to use right away. We offer every process in house, from external, internal and centreless grinding to CNC-controlled applications. We are also well versed in wire-cut and die-sinking erosion.
Last but not least, we subject our products to a final quality check to make sure they are up to standard and comply with the relevant specifications and drawings.
Powder processing
We use our own powder preparation systems to manage and control our cemented carbide compositions in house. The grinding/homogenisation and drying processes deliver a defined quantity of powder ready for compression.
Isostatic pressing
We use linear or isostatic pressing with forces of up to 30,000 kN to produce cylindrical or block-shaped blanks. In terms of hardness, these blanks are roughly equivalent to a piece of blackboard chalk.
Axial pressing
Axial pressing allows us to produce parts with accurate end contours using automatic pressing systems and tools that we produce in house. We also employ the same isostatic pressing process used to make cylindrical or block-shaped blanks.
Machining the blank
Based on the customer drawing, we machine the custom parts using conventional processes like turning, milling and grinding. We always pay attention here to the specific shrinkage that arises during sintering. When it comes to the choice of cutting material in the individual processing steps, we only use diamond-tipped tools that achieve excellent results efficiently.
Sintering
At Nadler Hartmetalle, we subject all parts to the sinter HIP process. This lets us ensure that the sintered parts have a uniform structure, and guarantees that the cemented carbide’s physical properties remain at a high and reproducible level.
As the sintering process causes the parts to shrink by around 25%, this needs to be taken into account in advance.
Grinding
For these final steps in the production of finished cemented carbide parts or tools, we use our modern and versatile in-house grinding machinery. This is suitable for all grinding operations, as well as lapping, polishing, honing and eroding.
Our team of grinding experts consists of both young and experienced specialists who are dedicated to achieving outstanding results. It is this that allows us to offer and guarantee excellent efficiency and expertise in cemented carbide finishing.
Eroding, lapping & honing
We perform both wire-cutting and die-sinking erosion processes in house. These two options allow us to create extremely precise contours with outstanding surface finishes.
Lapping is a highly efficient process that is suitable for medium-to-large batch sizes. It allows us to produce highly precise parallels at relatively low cost.
Honing is a removal process that can produce boreholes quickly and efficiently within a small tolerance range. Diamond-tipped honing stones can also help create outstanding cylindricity by means of cross-hatch.
Quality assurance
The cemented carbide parts are checked and documented where necessary on our measurement systems. The physical values are analysed in our laboratory after sintering.
This ensures consistent end product quality, meaning our customers can rest assured that they will only receive usable parts that meet their specifications.
