.
Oktober 2025 Microstructure of an edge-hardened gear with a ferrite-pearlite base structure, etched with 3% alcoholic nitric acid.
Fascininzichten in de materialografie-wereld staan u elke maand in 2025 te wachten! Verneem meer over onze boeiende preparaties of ontvang interessante tips & truuks van onze experten. Kijk uit naar onze maandelijkse hoogtepunten!
Weld seam between copper and steel sheets are used normally for the connection in electric devices. This weld seam is critical for ensuring electrical connectivity, mechanical stability, and thermal management. High-quality welds prevent energy loss, enhance safety, and improve battery longevity, making them essential for reliable performance in demanding applications such as electric vehicles and portable electronic devices.
A critical aspect of quality control for these weld seams is metallographic preparation and analysis. The process commences with precise sectioning, utilizing the Qcut 200 precision cut-off machine equipped with a rotating clamping device and a rubber-bonded Al₂O₃ cut-off disc, which ensures minimal deformation of the sheet materials during cutting. The selection of suitable mounting material is essential; it should exhibit minimal gap formation within the designated hardening period. KEM 20, an MMA-based mounting material, offers a hardening time of 15 minutes with exceptionally low gap occurrence. Final planar grinding with VEGA 125 µm ensures a uniformly flat surface and a high material removal rate.
The Ti-6Al-4V (Ti64) alloy, also known as Titanium Grade 5, is one of the most used titanium alloys in additive manufacturing. It combines different properties like strength, lightness and corrosion resistance, making it attractive to a wide range of industries, including aerospace, automotive and medical. A major advantage of Ti64 additive manufacturing is its ability to produce customized implants for medical applications. Cutting the samples with a precision cutting machine such as the QCUT 200 A prevents the sample from overheating or being mechanically deformed during the cutting process. Mounting with an epoxy resin mounting material and using an infiltration device helps to fill all pores before grinding/polishing. Using the correct consumables during grinding/polishing can prevent smearing and makes the pore percentage measurement more accurate. This month you can find out all these important points in our preparation of the month.
The trend of lightweight multi-material design (MMD) is becoming increasingly significant in the transportation sector, particularly in automotive applications. This trend is driven by the growing demands for sustainability, cost optimization, and performance enhancement. Multi-material design involves the strategic integration of different materials within a single component to meet specific technical requirements while enabling the production of economically efficient, lightweight parts. By leveraging the complementary properties of various materials, engineers can optimize the structural integrity, weight, and cost of vehicle components, leading to improved overall performance and resource efficiency.
Al/Fe bimetallic composites, as one of the multi-material series, offer a favorable combination of high strength and wear resistance from Fe (steel/cast iron) and high thermal conductivity, corrosion resistance, and lightweight properties from Al (aluminum alloys/ pure aluminum). This month, you will experience the metallographic preparation of these components, from cutting to fine polishing.
In a BGA (Ball Grid Array) printed circuit board, the solder balls are crucial for the electrical and mechanical connection between the BGA casing and the circuit board. The material of the solder balls is typically a lead-free alloy, as lead-containing solders are increasingly being avoided due to environmental and health regulations.
The most common lead-free alloy is SAC305. Such tin alloys offer a balance between melting point, mechanical strength and electrical conductivity. As an example, the melting point of SAC305 is around 217-221 °C, which is slightly higher compared to lead-containing solders.
The metallographic examination of a solder joint on a printed circuit board is a common examination as part of the quality assurance of printed circuit boards. This month's preparation shows you how this tin solder can be optimally prepared for microscopic examination.
Thermische spuitcoatings op basis van Al₂O₃ zijn belangrijke componenten in verschillende industriële toepassingen, vooral in gebieden waar oppervlakken moeten worden beschermd tegen hoge temperaturen en corrosieve omgevingen. Eigenschappen van spuitcoatings op basis van Al₂O₃ zijn onder meer hoge temperatuurbestendigheid, corrosiebestendigheid en slijtvastheid. Er zijn verschillende methoden van thermisch spuiten, waaronder: Plasmaspuiten, vlamspuiten en spuiten met zuurstofbrandstof met hoge snelheid (HVOF). Na de metallografische voorbereiding van deze coatings is de eerste vraag altijd of de coating correct is voorbereid en het beeld onder de lichtmicroscoop/SEM moet zijn zoals het is of dat de artefacten van het preparaat aanwezig zijn in mijn microstructuur. De voorbereidingsmethoden van QATM volgens DVS (Duitse Vereniging voor Lassen en Aanverwante Procedures) datasheets garanderen de juiste voorbereiding van de spuitwerende coatings zonder voorbereidingsartefacten.
The main component in the stators is the current-carrying coated copper wire. Copper is the preferred material for current-carrying parts in electric motors due to its favorable ratio of electrical and thermal conductivity and its moderate cost. In the hairpin process, copper wires are inserted into the grooves on the edge of the motor using a compressed air gun. Depending on the size of the stator, between 160 and 220 hairpins can be used, which must be processed within a maximum period of 60 to 120 seconds. After placement, the wires are twisted together and welded. This process requires maximum precision to ensure the electrical conductivity of the hairpins. This month's preparation explains how to prepare laser weld seam in a hairpins so that it can be analyzed under a microscope without preparation artefacts.
A hardness mapping is carried out to determine the hardness profile of a sample or a specific area comprehensively. By evenly distributing test points, local hardness differences and hardness profiles can be precisely analyzed. The hardness values are categorized into hardness ranges and highlighted with colors. In 3D mapping, a height value is additionally assigned to the hardness value.
Electrolytic etching of aluminum alloys is a process used to reveal the microstructure of aluminum and its alloys or to modify the surface in a targeted manner. The workpiece is placed in contact with a suitable electrolyte solution as an anode and an electrical voltage is applied. The electrochemical process dissolves individual phases/grains of the alloy differently, making it possible to visualize structural components, grain boundaries, or phase differences under a microscope. The choice of electrolyte and process parameters (voltage, current density, temperature, polishing/etching time) depends on the alloy and the desired etching result. Electrolytic etching offers the advantage of better control over the etching process compared to chemical etching and enables a more uniform and reproducible surface structure. In this month's preparation, you will learn the correct parameters for perfect electrolytic preparation with the QETCH 1000 and QATM-Barker solution.
CrCoMo alloys are distinguished by their excellent corrosion resistance, high strength, and outstanding biocompatibility. These properties make them preferred materials in medical technology, particularly for the fabrication of implants such as artificial hip and knee joints as well as dental prostheses. The alloys exhibit exceptional wear resistance and reliably maintain their mechanical properties even under high load and in contact with bodily fluids.
The addition of molybdenum further enhances corrosion resistance, while chromium promotes the formation of a stable, protective oxide layer on the surface. In addition to their use in the medical field, CrCoMo alloys are also applied in the aerospace and chemical industries, where the highest demands are placed on material durability.
A central aspect of quality assurance for CrCoMo alloys is metallographic examination. This includes microstructural analyses using light microscopy and scanning electron microscopy as well as the inspection for porosity, shrinkage cavities, and inclusions. In our “Preparation of the Month,” you will gain comprehensive insight into the complete preparation process for a CrCoMo alloy. Here, the Contero H fine grinding disc plays a decisive role: it is used between coarse grinding with a diamond disc and the polishing step, ensuring optimal preparation results. For this reason, we have selected the Contero H fine grinding disc as our Product of the Month.
Weld seam between copper and steel sheets are used normally for the connection in electric devices. This weld seam is critical for ensuring electrical connectivity, mechanical stability, and thermal management. High-quality welds prevent energy loss, enhance safety, and improve battery longevity, making them essential for reliable performance in demanding applications such as electric vehicles and portable electronic devices.
A critical aspect of quality control for these weld seams is metallographic preparation and analysis. The process commences with precise sectioning, utilizing the Qcut 200 precision cut-off machine equipped with a rotating clamping device and a rubber-bonded Al₂O₃ cut-off disc, which ensures minimal deformation of the sheet materials during cutting. The selection of suitable mounting material is essential; it should exhibit minimal gap formation within the designated hardening period. KEM 20, an MMA-based mounting material, offers a hardening time of 15 minutes with exceptionally low gap occurrence. Final planar grinding with VEGA 125 µm ensures a uniformly flat surface and a high material removal rate.
