In-house materials laboratory

A source of insight

Magnetic values, density, structure, grain size, porosity, specific weight – Ihle is the only carbide supplier that metallurgically inspects these key quality characteristics and can guarantee the high quality of its products. The high-end measuring instruments in our in-house laboratory enable reliable precise quality analyses and grade determinations to be carried out. This result is a level of reliability that benefits tool manufacturers as well as users and end users.

Especially since we also test products from other brands besides Ihle: the laboratory has become established as an independent testing centre for carbide. Our judgement, our grade recommendations and tests of tool damage and wear and tear are in demand. After all, the quality of the carbide affects more than just the tool quality, it also has a considerable effect on the production costs and the profitability of tool production.

Process and production reliability

The seamless, meticulous checks carried out by our materials laboratory is a guarantee of the first-class – and rigorously documented – quality of our carbide bars. This is how we ensure our high standards with regard to suppliers and offer all customers constant process reliability.

We make our sound expert knowledge available to our customers at all times – for optimum process and production reliability.

Fully-automatic measuring system for round bars for checking diameter, roundness and bending with a laser micrometre

Technical advice and service

Our materials laboratory has made a name for itself as an independent, professional testing centre for carbide. Thanks to many years of experience, in-depth know-how and state-of-the-art laboratory equipment, we are experts at evaluating carbides with accuracy. If requested, we can advise our customers on the most suitable carbide grade for their specific project and how to use it. In addition to metallurgical analyses, we also carry out practical tests for examining tools. A service normally only available from large carbide manufacturers.

  • Grade determination
  • Density
  • Hardness [HV30 and KIC, if required HV10 / HRA]
  • Coercivity
  • Magnetic saturation
  • Structural assessment
    • Porosity
    • TC grain size and grain size distribution
    • Metallic binder distribution
    • Metallographic phase analysis
      • Carbon
      • Eta phase
      • Mixed carbide
  • Bending strength
  • Documentation of all test results and photos
  • Examinations using scanning electron microscopy

Carbide grade determination

Carbide grades are often defined by just the grain size and the cobalt content. But this simply isn’t enough. Ultimately, a whole range of physical characteristics affect the quality and grade identification of a carbide. This is why our specialists determine properties such as magnetic saturation, specific weight and examine the microscopic structure. These results are essential for identifying the best carbide for your specific requirements.

Damage and material analysis

A metal-cutting tool is a complex system, consisting of the base material, the cutting-edge geometry and, in some cases, the coating. These individual components must work in perfect harmony to deliver an optimum result on the workpiece. Should problems with service life or even tool breakages occur when using the tools, then the cause needs to be found. As an independent test centre for carbide, Ihle is an expert at finding answers. Our detailed test reports and recommendations help our customers to optimise their operating processes.

Analyses in detail


The coercivity (Hc) signifies the magnetic field strength that is required to fully demagnetize a ferromagnetic substance. Magnetic properties give insight into the material structure.

Static evaluation during incoming goods inspection
Destruction-free testing of carbides
Magnetic saturation

By measuring weight-specific magnetic saturation, we are able to quickly determine the sintered state and carbon balance, and in turn, quickly make a judgement about the quality of the carbide in question.

All established values can be directly forwarded to the customer on request
Magnetic saturation measurement using a Helmholtz coil
Microscopic analysis

The Leica microscope does everything you need: the up to 2000x magnification enables aspects such as structure, porosity, eta-phase, binder metal distribution and grain size to be thoroughly determined. Output on imaging media is possible for analysis and documentation.

Image of a TC coarse grain in a fine grain carbide
Leica laboratory microscope: top quality optics and high precision lenses
Hardness test

Hardness testing according to Vickers involves pressing a diamond pyramid into the workpiece using a stipulated test force. The Vickers hardness (HV) and the KIC value can be derived using a measuring microscope. Both values play a vital role in the evaluation of hardness, wear resistance and fracture toughness.

Hardness indentation with fracture formation to determine the KIC value
Hardness test with 30 kN test load
Density measurement

To exactly determine the specific weight and measure the weight-specific magnetisation saturation, we use a Sartorius precision balance. The density is primarily an indicator of the binder metal content.

The balance gives the weight to the nearest one thousandth of a gram
Highly precise measurement is necessary – even the water temperature is taken into account
Stereo microscope

This microscope is used for initial brief observation of material samples. Up to 150x magnification enables the assessment of tool breakage or wear on cutting edges. Imaging is also possible via the connected camera.

This microscope is used for initial brief observation of material samples. Up to 150x magnification enables the assessment of tool breakage or wear on cutting edges. Imaging is also possible via the connected camera.
A wide field of view and simple handling enable quick and reliable statements to be made
Cutting-off machine

For our sample cuttings, we use cutting-off machines manufactured by G.u.K. Ihle, which enable quick, plane-parallel cutting while also offering short setup and cutting times. Four different types are available ranging from the manually operated machine to the fully automatic system with loading magazine.

Finely polished carbide sample, cast in epoxy resin for microscopic analysis
The IB1: a successful model for many years − enables plane-parallel sample cuttings
Bending strength

The bending strength depends on the cobalt content and the grain size of the carbide. It is determined by conducting a destructive test on standard samples in accordance with DIN EN ISO 3327. The test involves increasingly loading the specimens to failure.
The bending strength is a direct indication of the loading capacity of the carbide in practical use. Because of the wide distribution of measurements, several samples must be tested to failure in order to obtain meaningful evaluations.

Testing the bending strength in accordance with DIN EN ISO 3327-2006
Field trials

Our metallurgical examinations are complemented by milling tests to assess and further develop carbides. We perform life tests for our customers to determine the most suitable grade of carbide for complex materials and conditions.

The grade of carbide has a major influence on the tool life travel and the machinability of the tool
Milling cutters undergo vigorous testing