Characterisation of the carrier of distortion potential “residual stresses” in the collaborative research centre “distortion engineering”

Abstract

Charakterisierung des Verzugspotenzialträgers "Eigenspannungen" im Sonderforschungsbereich "Distortion Engineering" J. Epp, T. HirschAs residual stresses are already known as important distortion potentials, a comprehensive characterisation of residual stress distributions is required. In order to get this information, several techniques that are often complementary have to be used. Every method has its own advantages but also presents difficulties. In this paper, three methods (X-ray diffraction, neutron diffraction and micromagnetic methods) used for the characterisation of residual stress states of different components will be presented. Some basics about theory and application of the methods are given. Concrete examples and results are shown. In particular, residual stress characterisation of bearing rings made from the steel grade AISI52100 and carburized discs made from AISI5120 are presented. A comparison of the methods with their specific advantages and disadvantages is made.Keywords: X-ray diffraction / neutron diffraction / micromagnetic method / residual stresses / Eigenspannungen wurden bereits als wichtige Verzugspotenzialträger identifiziert und es ist deswegen von hoher Wichtigkeit, die Verteilung dieser Eigenspannungen innerhalb eines Bauteils zu charakterisieren. Um an diese Informationen heranzukommen, stehen mehrere Möglich-keiten zur Verfügung, welche sich oft gut ergänzen. Jede Messmethode hat eigene Vorteile, bringt jedoch ebenfalls Schwierigkeiten mit sich. In diesem Artikel werden drei Methoden zur Eigenspannungsbestimmung vorgestellt (Röntgen-beugung, Neutronenbeugung und ein mikromagnetisches Verfahren), welche für die Charakterisierung von unterschiedlichen Bauteilen angewendet wurden. Einige Grundinformationen über die jeweiligen Verfahren werden zunächst vorgestellt und im Anschluss konkrete Anwendungsbeispiele gezeigt. Insbesondere werden Messungen an Wälzlagerringen aus dem Stahl AISI52100 sowie an Scheiben als Modellbauteil für Zahnräder aus dem Einsatzstahl AISI5120 vorgestellt. Anschließend werden die Methoden verglichen und hinsichtlich ihrer Vor-und Nachteile bewertet.Schlüsselwörter: Röntgenbeugung / Neutronenbeugung / mikromagnetisches Verfahren / Eigenspannungen /

Distortion Analysis in the Manufacturing of Cold-Drawn and Induction-Hardened Components

“…Residual stress relief effects for AISI 1045 steel in different material states can be calculated according to equations given in. [18] Residual stresses at surface and after 50-lm layer removal proved to be near zero. It is so far obvious that drawing and P.S.-induced residual stresses could be relieved after stress relief.…”

“…It is so far obvious that drawing and P.S.-induced residual stresses could be relieved after stress relief. [18] Inductionhardened bars after stress relief consist of a surfacehardened layer with hardness depth profiles from Figure 9(a).…”

Investigation of the Influence Factors on Distortion in Induction-Hardened Steel Shafts Manufactured from Cold-Drawn Rod

“…Residual stresses were analyzed by X-ray diffraction (XRD) using the conventional sin 2 w-method. [12,13] A diffractometer (GE Inspection Technologies, Type MZ VI) with Vanadium filtered Cr-Ka-radiation was employed. A primary beam aperture of 2 mm diameter and a scintillation counter with a 2-mm secondary slit for detecting the diffracted beam were used for the local analysis along the length and around the periphery of the drawn cylinders.…”

“…The {211} diffraction peak of a-iron was measured. [12,13] The Full Width at Half Maximum (FWHM) values of the diffraction peaks are also evaluated, which give further information about microstresses and crystallite size in the microstructure. The AISI 1045 steel contains about 6.7 vol pct of cementite (Fe 3 C) in initial heat treatment condition.…”

The evolution of manufacturing processes for micro‐featured epoxy resin mold

“…Figure 24 shows the residual stresses distribution of the parts fabricated by micro-hot embossing and micro-injection molding. This result clearly demonstrated that the part fabricated by the micro-hot embossing molding has lower residual stresses due to the polymers flow a very short distance from the PMMA film into microstructures of the epoxy resin mold during the micro-hot embossing process [29,30]. Residual stresses in the plastic optical components were induced by solidification process [31].…”