Metallography

Metallographic investigations consent to determine the physical structure of metals; on several levels of examination (at the macrographic or micrographic level) and with more techniques in combination, it is underlined the size and shape of the crystals, the grains, the distribution of the phases, the level of purity and the presence of any contaminant in the material (inclusions), the type of heat treatment, the direction of the lines of slip or flow in case of samples plastically deformed, the thickness of the coatings.

This type of tests are also used for the characterization and study of the welds, or for certification of processes and personnel (welders, brazers, welding operators).

Lab technicians use of most modern equipment: metallographic microscope, stereo microscope, scanning electron microscope SEM. Metallography's Cutting, polishing and chemical attack are carried out internally.

Metallographic Exams
  • Micrographic examination
  • Grain Size - With Controlled Oxidation Kohn Method
  • Grain Size - Direct Attack Method
  • Grain Size - Bechet-Beaujard Method
  • Austenitic Grain Size - McQuaid-Ehn Method
  • Cementation Depth (Optical Method)
  • Cementation Depth (Hardness Resistance Seams)
  • Corrosion Depth (Optical Method)
  • Decarburisation Depth (Optical Method)
  • Decarburisation Depth (Hardness Resistance Seams)
  • Nitriding Depth (Optical Method)
  • Nitriding Depth (Hardness Resistance Seams)
  • Coating Thickness Determination (Optical Method)
  • Banding Index Determination According to ASTM E1268 (Fiber Profile)
  • Carbide Determination (Optical Method)
Inclusions
  • Non-Metallic Inclusions Determination ISO 4967 Method A, Method B
  • Non-Metallic Inclusions Determination According to Customer Specification
  • Non-Metallic Inclusions Determination UNI 3244 Method K < 4
  • Non-Metallic Inclusions Determination UNI 3244 Method K >e; 4
  • Inclusions Determination According to ASTM E45 Method A, Method D
  • Phase Percentage (Duplex Grid 100 Pts + Check 20 Fields - Rel. Accuracy 10% Tab.3)
  • Phase Percentage (Duplex Grid 16 Pts + Check 30 Fields - Rel. Accuracy 20% Tab.3)
Macrographic Exams
  • Fractography
  • Macrographic examination
Failure Analysis - Breakage Causes

Through the combination of more research techniques, it is possible to determine the assumptions that led to a component or a metallic product failure. The use of the scanning electron microscope SEM allows to uniquely determine the type of failure, while a systematic methodology and punctual joined to the remaining tests Laboratory directs the crew towards the formulation of hypotheses relatively to the phenomenon of failure occurred.

  • Failure Investigation On Metallic Artifact
  • Corrosion Failure Investigation
  • SEM: Microanalysis EDS + Spectrum
  • SEM: High Vacuum Examinations (Metallic Samples)
  • SEM: Variable Pressure Examinations (Non-Metallic Samples)
Metallographic Replicas

A metallographic replica is a particular type of metallographic examination that allows the intervention of technical personnel directly on the finished article without having to intervene mechanically with cuts or sectioning for removing the particular to analyze. This type of investigation is carried out at the headquarters of the Client; it highlights the structure and morphology of the surface of the material through a sequence of operations that sees primarily a suitable preparation of the surface to then perform a chemical attack specific to the type of material under investigation.

  • Metallographic Replicas

Download the complete list of the activities done in the Metallographic Dept.

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