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View article: Electrode and process design for regulation of liquid metal embrittlement phenomenon during spot welding of dual-phase steel: numerical modelling and experiments
Electrode and process design for regulation of liquid metal embrittlement phenomenon during spot welding of dual-phase steel: numerical modelling and experiments Open
Thermal and mechanical loading, combined with zinc coating, are the primary factors influencing liquid metal embrittlement (LME) in the investigated advanced high-strength dual-phase steel, with a yield strength of 1200 MPa and high ductil…
View article: Modeling solute drag during austenite–ferrite transformation with ab initio binding energies
Modeling solute drag during austenite–ferrite transformation with ab initio binding energies Open
The solute drag effect can have a considerable impact on the austenite to ferrite transformation. Most models describing the solute drag effect require knowledge of solute binding energies, which due to lack of accurate data typically are …
View article: Numerical and experimental assessment of liquid metal embrittlement in externally loaded spot welds
Numerical and experimental assessment of liquid metal embrittlement in externally loaded spot welds Open
Zinc-based surface coatings are widely applied with high-strength steels in automotive industry. Some of these base materials show an increased brittle cracking risk during loading. It is necessary to examine electrogalvanized and uncoated…
View article: A Comprehensive Material Model for the Super-Duplex Stainless Steel SAF2507 in a Welding Environment
A Comprehensive Material Model for the Super-Duplex Stainless Steel SAF2507 in a Welding Environment Open
The aim of this work is to describe a reliable methodology for determining parameters of a material model suitable for implementation in a welding simulation using the finite element method (FEM). The adopted methodology employs a multi-sc…
View article: Numerical Analysis of Convective Mass Transfer during Multi-Droplet Impingement on a Structured Surface in the Presence of an Adhered Liquid Film—An Application to Spray Etching of PCBs
Numerical Analysis of Convective Mass Transfer during Multi-Droplet Impingement on a Structured Surface in the Presence of an Adhered Liquid Film—An Application to Spray Etching of PCBs Open
Multi-droplet impingement is a fundamental aspect inherent to all kinds of technical spray processes which typically aim at enhancing the convective exchange of reagents or heat at the impinged surface. In this paper, the impingement of mu…
View article: Influence of the aspect ratio of the micro-cantilever on the determined Young’s modulus using the Euler-Bernoulli equation
Influence of the aspect ratio of the micro-cantilever on the determined Young’s modulus using the Euler-Bernoulli equation Open
Micro-cantilever bending experiments can be used to determine fundamental material properties, such as fracture stress and fracture toughness. Furthermore, the Young's modulus can be calculated from the slope of the load-displacement curve…
View article: Interstitial Segregation has the Potential to Mitigate Liquid Metal Embrittlement in Iron
Interstitial Segregation has the Potential to Mitigate Liquid Metal Embrittlement in Iron Open
The embrittlement of metallic alloys by liquid metals leads to catastrophic material failure and severely impacts their structural integrity. The weakening of grain boundaries (GBs) by the ingress of liquid metal and preceding segregation …
View article: Residual Stress Evolution in Low-Alloyed Steel at Three Different Length Scales
Residual Stress Evolution in Low-Alloyed Steel at Three Different Length Scales Open
Quantitative and qualitative residual stress evolution in low-alloyed steel during heat treatment is investigated on three different length scales for sourgas resistant seamless steel tubes: on the component level, on the level of interden…
View article: Interstitial Segregation has the Potential to Mitigate Liquid Metal Embrittlement in Iron
Interstitial Segregation has the Potential to Mitigate Liquid Metal Embrittlement in Iron Open
The embrittlement of metallic alloys by liquid metals leads to catastrophic material failure and severely impacts their structural integrity. The weakening of grain boundaries by the ingress of liquid metal and preceding segregation in the…
View article: Hydrogen assisted intergranular cracking of alloy 725: The effect of boron and copper alloying
Hydrogen assisted intergranular cracking of alloy 725: The effect of boron and copper alloying Open
To overcome the Hydrogen embrittlement (HE) susceptibility of the standard Alloy 725 (Mod A), two alloys with minor alloying modifications with B (Mod B) and B+Cu (Mod C) were produced. Then, the intergranular cracking susceptibility was i…
View article: Grain boundary segregation in Ni-base alloys: A combined atom probe tomography and first principles study
Grain boundary segregation in Ni-base alloys: A combined atom probe tomography and first principles study Open
Grain boundary engineering (GBE) plays an important role in the design of new polycrystalline materials with enhanced mechanical properties. This approach has been shown to be very effective in design of Ni-base alloys, where grain boundar…
View article: Liquid Metal Embrittlement of Advanced High Strength Steel: Experiments and Damage Modeling
Liquid Metal Embrittlement of Advanced High Strength Steel: Experiments and Damage Modeling Open
In the automotive industry, corrosion protected galvanized advanced high strength steels with high ductility (AHSS-HD) gain importance due to their good formability and their lightweight potential. Unfortunately, under specific thermomecha…
View article: Validated Multi-Physical Finite Element Modelling of the Spot Welding Process of the Advanced High Strength Steel DP1200HD
Validated Multi-Physical Finite Element Modelling of the Spot Welding Process of the Advanced High Strength Steel DP1200HD Open
Resistance spot welding (RSW) is a common joining technique in the production of car bodies in white for example, because of its high degree of automation, its short process time, and its reliability. While different steel grades and even …
View article: Strength ranking for interfaces between a TiN hard coating and microstructural constituents of high speed steel determined by micromechanical testing
Strength ranking for interfaces between a TiN hard coating and microstructural constituents of high speed steel determined by micromechanical testing Open
Knowledge about the adhesion of protective hard coatings on tool materials is of great importance to understand their failure mechanisms in metalworking. Until now, common techniques such as scratch and indentation tests are used to establ…
View article: Analysis of Sn-Bi Solders: X-ray Micro Computed Tomography Imaging and Microstructure Characterization in Relation to Properties and Liquid Phase Healing Potential
Analysis of Sn-Bi Solders: X-ray Micro Computed Tomography Imaging and Microstructure Characterization in Relation to Properties and Liquid Phase Healing Potential Open
This work provides an analysis of X-ray micro computed tomography data of Sn-xBi solders with x = 20, 30, 35, 47, 58 wt.% Bi. The eutectic thickness, fraction of eutectic and primary phase are analyzed. Furthermore, the 3D data is evaluate…
View article: Modelling of Void Collapse with Molecular Dynamics in Pure Sn
Modelling of Void Collapse with Molecular Dynamics in Pure Sn Open
This work simulates the collapse of a spherical void in pure Sn during melting using molecular dynamics (MD). Simulations were performed for two temperatures with a modified embedded atom method (MEAM) potential, which was reported to be i…
View article: Addressing H-Material Interaction in Fast Diffusion Materials—A Feasibility Study on a Complex Phase Steel
Addressing H-Material Interaction in Fast Diffusion Materials—A Feasibility Study on a Complex Phase Steel Open
Hydrogen embrittlement (HE) is one of the main limitations in the use of advanced high-strength steels in the automotive industry. To have a better understanding of the interaction between hydrogen (H) and a complex phase steel, an in-situ…
View article: Nanoscale stress distributions and microstructural changes at scratch track cross-sections of a deformed brittle-ductile CrN-Cr bilayer
Nanoscale stress distributions and microstructural changes at scratch track cross-sections of a deformed brittle-ductile CrN-Cr bilayer Open
In order to interpret the mechanical response of thin films subjected to scratch tests, it is necessary to elucidate local stress distributions and microstructural changes accompanying deformation across the scratch track area. Here, 50 nm…
View article: Hydrogen Trapping in bcc Iron
Hydrogen Trapping in bcc Iron Open
Fundamental understanding of H localization in steel is an important step towards theoretical descriptions of hydrogen embrittlement mechanisms at the atomic level. In this paper, we investigate the interaction between atomic H and defects…
View article: Elasto-Viscoplastic Material Model of a Directly-Cast Low-Carbon Steel at High Temperatures
Elasto-Viscoplastic Material Model of a Directly-Cast Low-Carbon Steel at High Temperatures Open
A model-based process control of material production processes demands realistic material models describing the local evolution of the thermal and mechanical state variables, i.e., temperature, stress, strain, or plastic strain, for the re…
View article: An SEM compatible plasma cell for <i>in situ</i> studies of hydrogen-material interaction
An SEM compatible plasma cell for <i>in situ</i> studies of hydrogen-material interaction Open
An in situ hydrogen (H) plasma charging and in situ observation method was developed to continuously charge materials, while tensile testing them inside a scanning electron microscope (SEM). The present work will introduce and validate the…
View article: Model-Based Residual Stress Design in Multiphase Seamless Steel Tubes
Model-Based Residual Stress Design in Multiphase Seamless Steel Tubes Open
Residual stresses in quenched seamless steel tubes highly depend on the cooling conditions to which the tubes have been subjected. The design aspect of how to use controlled cooling strategies in multiphase steel tubes to achieve certain r…
View article: Inverse Model for the Control of Induction Heat Treatments
Inverse Model for the Control of Induction Heat Treatments Open
In this work, we present and test an approach based on an inverse model applicable to the control of induction heat treatments. The inverse model is comprised of a simplified analytical forward model trained with experiments to predict and…