Fascinating insights into the world of materialography await you every month in 2024! Find out more about our exciting preparations or get interesting tips and tricks from our experts. Look forward to our monthly highlights!
Ledeburite is a eutectic mixture of cementite (Fe3C) and austenite (γ-Fe), which formed in iron-carbon alloys. Ledeburite-II consists of cementite-I with recrystallized secondary cementite + perlite. This eutectic mixture is formed during the cooling of iron-carbon melts with a carbon content of around 2.06 to 6.67 % by weight. The name comes from the German metallurgist Karl Heinrich Adolf Ledebur, who lived and worked in the 19th century. In this month's preparation, you will see how steels containing ledeburite can be prepared metallographically. The samples were cut using the QCUT 350 A with the Al2O3 cutting disc FS-E, which is suitable for hard steels, hot-embedded with EPO black and ground and polished to 1 µm using the QPOL 300 A1. The 3% alc. Nitric acid was used as etchant.
Microstructure of a cast aluminum alloy, electrolytically etched with Barker etchant.
In the laboratory, hot mounting, cold mounting or light-induced mounting can be used. Our practical selection guide helps you choosing a suitable mounting method and offers you an appropriate mounting material for your specific requirements and application.
Microstructure of a steel TIG weld, etched with nitric acid
Lithium-ion battery technology has made enormous progress in recent decades, from the first Li-metal anodes to today's commercial batteries. At QATM, we focus on comprehensive quality control and offer analysis methods such as grain size determination and layer thickness measurement on LIB samples, supported by our fully automated Qness 60 A+ EVO microhardness tester.
Analysis of the solder joint of a ceramic capacitor: The samples were successfully separated, mounted, and prepared; etching was not necessary. The aim is to detect pores or other defects. An important step on the way to quality assurance and fault analysis in electronics production.
Additive-manufacturing, also known as 3D printing, is a revolution in the way of production. Complex structures can be produced with high precision by applying material layer by layer. This technology enables customized production and reduces waste, making it particularly attractive for prototyping, special products and sustainable production processes. As the complexity of parts increases, the difficulty and importance of quality control and non-destructive as well as destructive testing as part of quality control increases considerably. The metallographic preparation of additively manufactured samples requires suitable equipment and sufficient expertise. It is also essential to determine the preparation artefacts from manufacturing defects. In the preparation of this month, you will learn how to prepare an additive-manufactured steel sample free of scratch and deformations.
The GALAXY Contero H is an innovative fine grinding disc for diamond suspensions from 15 to 6 μm. It is easy to use, ready to use and maintenance-free. The grinding disc enables outstanding flatness, high material removal and excellent edge sharpness. Multi-stage grinding and pre-polishing are combined in one preparation step. It is ideal for medium-hard to hard steels from 300 HV and is particularly suitable for: Microstructural investigations close to the edge
CFRP, a composite material, has seen a growing application in the construction sector. It is made of carbon fibers embedded into a polymer matrix, which enhances the material's stiffness, strength, and durability. A common way to control the quality of the manufactured CFRP plates is to do the metallographic analyses. To prepare the CFRP without artifacts, each step in a metallographic preparation is crucial. Cutting the plates should be done without any deformation and heat generation.
QATM's diamond cut-off wheels of can deliver the best cutting results without any heat generation or smearing the material at the edge of the wheel. Mounting the plates should be done with a mounting material with minimum hardening temperature (like epoxy resin mounting material). The use of an infiltration device is not recommended as the distinction between the mounting material and the polymer matrix is not simple. Grinding and polishing with an automatic dosing system can significantly increase the reproducibility of the preparation. In this article you can find all the important information about the metallographic preparation of CFRP plates.
Microstructure of a additive manufactured copper alloy, after etching with Copper A etchant.
Standard manufacturing techniques for copper alloys, including powder metallurgy (PM) and traditional methods like machining, forging, , casting, and extrusion do not have the flexibility to handle complicated designs. Therefore, additive manufacturing is an alternative for producing copper segments with complex shapes. The physical and mechanical properties of additively manufactured (AM) samples depend on their mass density and microstructure. To analyze these two characteristics, metallographic preparation of the parts is required. To obtain a reliable result, deformation should be avoided during the entire preparation process.
Using the wet cutting process with suitable machine, consumables and parameters is a good starting point, which should be followed by the correct mounting method.
By using epoxy-based cold mounting material with the support of an infiltration device, the porous AM specimens can be suitably mounted. Grinding and polishing the AM specimens should also prevent smearing and pore closure. In the September report you will discover the correct preparation method for AM copper samples.
The first source of error for faulty investigations lies in the sampling and cutting process. Artefacts occurring here increase misinterpretations during the evaluation of the microstructure. The usual problems by cutting the normal parts can become chaotic by the large components. This month you can experience the process of cutting for a clutch housing and a differential drive. Qcut 400 A and 500 A, QATM premium Al2O3 cut-off wheels (such as FS-C ø 400 and ø 500 mm) and QATM standard anti corrosion coolant ensure optimum results during cutting of these large parts.
Electrolytic polishing and etching is an appropriate preparation method with less deformation for non-ferrous materials and materials with a single-phase microstructure that must later be analyzed under an EBSD detector. Electrolytic polishing directly on the finished part can save time and costs by avoiding the normal grinding/polishing process. A well-known application of electrolytic etching is the use of Barker solution to enable color etching in Aluminum alloys. The etching affects the individual grains of the microstructure depending on their orientation. If the etched samples are viewed under linearly polarized light, the differently oriented grains appear in various colors. With this method, the direction of growth in the investigated plane can be easily recognized and the size of the grains can be measured.
Ledeburite is a eutectic mixture of cementite (Fe3C) and austenite (γ-Fe), which formed in iron-carbon alloys. Ledeburite-II consists of cementite-I with recrystallized secondary cementite + perlite. This eutectic mixture is formed during the cooling of iron-carbon melts with a carbon content of around 2.06 to 6.67 % by weight. The name comes from the German metallurgist Karl Heinrich Adolf Ledebur, who lived and worked in the 19th century. In this month's preparation, you will see how steels containing ledeburite can be prepared metallographically. The samples were cut using the QCUT 350 A with the Al2O3 cutting disc FS-E, which is suitable for hard steels, hot-embedded with EPO black and ground and polished to 1 µm using the QPOL 300 A1. The 3% alc. Nitric acid was used as etchant.