Influence of machining processes on rim zone properties and high temperature oxidation behavior of 42CrMo4

Zander, Daniela; Klink, Andreas; Harst, Simon; Klocke, Fritz; Altenbach, Christoph

doi:10.1002/maco.201910928

Cited by 13 publications

(8 citation statements)

References 43 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It is usually machined with abrasive (e.g., grinding) or thermal processes (e.g., electric discharge machining). These abrasive or thermal processes lead to undesired changes in the rim zone, such as white layers, residual stresses, or heat-affected zones, which might have a negative effect on the functionality of the component [ 8 , 9 , 10 ]. Recent results after ECM in sodium nitrate revealed that processing and surface finishing by ECM does not lead to the formation of the previously mentioned changes in the rim zone.…”

Section: Introductionmentioning

confidence: 99%

“…Recent results after ECM in sodium nitrate revealed that processing and surface finishing by ECM does not lead to the formation of the previously mentioned changes in the rim zone. In addition, ECM enables the removal of these undesirable rim zone modifications and the adjustment of improved surface properties [ 8 , 11 ]. However, in addition to the advantages mentioned, the ECM process also shows disadvantages.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Oxide Formation during Transpassive Material Removal of Martensitic 42CrMo4 Steel by Electrochemical Machining

et al. 2021

Self Cite

View full text Add to dashboard Cite

The efficiency of material removal by electrochemical machining (ECM) and rim zone modifications is highly dependent on material composition, the chemical surface condition at the break through potential, the electrolyte, the machining parameters and the resulting current densities and local current density distribution at the surfaces. The ECM process is mechanistically determined by transpassive anodic metal dissolution and layer formation at high voltages and specific electrolytic compositions. The mechanisms of transpassive anodic metal dissolution and oxide formation are not fully understood yet for steels such as 42CrMo4. Therefore, martensitic 42CrMo4 was subjected to ECM in sodium nitrate solution with two different current densities and compared to the native oxide of ground 42CrMo4. The material removal rate as well as anodic dissolution and transpassive oxide formation were investigated by mass spectroscopic analysis (ICP-MS) and (angle-resolved) X-ray photoelectron spectroscopy ((AR)XPS) after ECM. The results revealed the formation of a Fe3−xO4 mixed oxide and a change of the oxidation state for iron, chromium and molybdenum, e.g., 25% Fe (II) was present in the oxide at 20.6 A/cm2 and was substituted by Fe (III) at 34.0 A/cm2 to an amount of 10% Fe (II). Furthermore, ECM processing of 42CrMo4 in sodium nitrate solution was strongly determined by a stationary process with two parallel running steps: 1. Transpassive Fe3−xO4 mixed oxide formation/repassivation; as well as 2. dissolution of the transpassive oxide at the metal surface.

show abstract

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Oxide Formation during Transpassive Material Removal of Martensitic 42CrMo4 Steel by Electrochemical Machining

et al. 2021

Self Cite

View full text Add to dashboard Cite

show abstract

“…The topography of the machined surfaces was geometrically characterized according to DIN EN ISO 16610-21 [29] and DIN EN ISO 16610-31 [30] by using a Marsurf XC. Roughness parameters, such as average roughness value (R a ), average peak-to-valley height (R z ), and maximum peak-to-valley height (R max ) of at least three samples per T A B L E 1 Chemical composition of 42CrMo4 steel [8] Element wt% at% surface condition were measured via the profile method and evaluated with the MarWin 9.0 evaluation program. Furthermore, the developed interfacial area ratio (Sdr) was calculated from roughness profiles, obtained by using a Tosca400 atomic force microscope (AFM) from Anton Paar.…”

Section: Microstructure and Topography Of Ground And Edm 42crmo4 Rim Zonesmentioning

confidence: 99%

“…However, this leads to undesired changes in the rim zone, such as the generation of residual stresses, changes in the microstructure, partial melting, or the formation of heataffected zones, which might have a negative effect on the functionality of the component. [8][9][10] In this case, the ECM process provides a high potential for postprocessing components, manufactured by mechanical or thermal methods, to remove undesirable rim zone modifications and improve surface integrity.…”

mentioning

confidence: 99%

Impact of rim zone modifications on the surface finishing of ferritic–pearlitic 42CrMo4 using electrochemical machining

Zander

Schupp

Mergenthaler

et al. 2021

Materials & Corrosion

Self Cite

View full text Add to dashboard Cite

The efficiency of material removal using electrochemical machining (ECM) is highly dependent on the initial rim zone modifications of the material to be processed. The influence of the rim zone modifications, such as topography and microstructure, on ECM, is investigated on ferritic–pearlitic 42CrMo4 steel by experiment and simulation. 42CrMo4 steel in two different premachining states—ground and electric discharge machined (EDM)—is subjected to a subsequent surface finishing by ECM in sodium nitrate solution. Before and after ECM, the topography and microstructure are examined using scanning electron microscopy, X‐ray diffractometer, and topography analysis methods. The electrochemical properties of the material are determined by potentiodynamic polarization. The efficiency of surface finishing by ECM is quantified by mass spectroscopic analysis (inductively coupled plasma mass spectrometry) of the process electrolyte and related to the rim zone modifications by simulation. The results reveal that the efficiency of material removal during ECM is higher for EDM than for ground 42CrMo4. This is attributed to an increased roughness of EDM 42CrMo4 and to the unfavorable electrochemical properties of the cementite phase in ground 42CrMo4.

show abstract

“…The use of materials for engine components, such as cylinders, requires both excellent mechanical properties and sufficient high-temperature corrosion resistance. It has been reported that the high-temperature oxidation behavior of 42CrMo4 steel, which is used for crankshafts, for example, depends on rim zone properties such as residual stresses, roughness and chemical composition [ 1 ]. These rim zone properties are determined by the mechanical, thermal, thermo-chemical or chemical loads of the applied manufacturing process.…”

Section: Introductionmentioning

confidence: 99%

Change of Oxidation Mechanisms by Laser Chemical Machined Rim Zone Modifications of 42CrMo4 Steel

et al. 2021

Self Cite

View full text Add to dashboard Cite

The oxidation mechanism of metals depends, among other factors, on the surface integrity. The surface and rim zone properties are often determined by the manufacturing process that was used to machine the material. Laser chemical machining (LCM) is a manufacturing process that uses laser radiation as a localized and selective heat source to activate a chemical reaction between an electrolyte and a metallic surface. The objective of this work is first to investigate how different LCM processes affect the rim zone properties of 42CrMo4. For this purpose, the surface chemistry is analyzed by EDS and XPS, phases and residual stresses are determined by XRD, and the morphology is investigated by SEM. Second, the influence of these modified rim zones on the oxidation properties of the steel at 500 °C in air is to be demonstrated in oxidation tests by in situ XRD and subsequent SEM/EDS investigations. A decisive influence of the oxides formed on the surface of 42CrMo4 during LCM in different electrolytes (NaNO3 solution and H3PO4) at two different laser powers on the high-temperature oxidation properties was demonstrated. These oxides were supposed to act as nucleation sites for oxide layer formation at 500 °C and led to an overall increase in oxide layer thickness after high-temperature oxidation compared to non-LCM-processed surfaces.

show abstract

Influence of machining processes on rim zone properties and high temperature oxidation behavior of 42CrMo4

Cited by 13 publications

References 43 publications

Oxide Formation during Transpassive Material Removal of Martensitic 42CrMo4 Steel by Electrochemical Machining

Oxide Formation during Transpassive Material Removal of Martensitic 42CrMo4 Steel by Electrochemical Machining

Impact of rim zone modifications on the surface finishing of ferritic–pearlitic 42CrMo4 using electrochemical machining

Change of Oxidation Mechanisms by Laser Chemical Machined Rim Zone Modifications of 42CrMo4 Steel

Contact Info

Product

Resources

About