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Fe 50 Co 50 was subjected to incremental forming by rotary swaging with the aim of tailoring the coercivity by changing the microstructure. The challenging part of a deformation of Fe 50 Co 50 is an ordering phase present at room temperature, leading to low formability. To increase the formability of the alloy the presence of the ordering phase was supressed by two different concepts. The first concept consists of a heat treatment above the phase transition followed by rapid cooling and deformation at room temperature. The second concept was rotary swaging at temperatures above the phase transition temperature. A comparison in terms of resulting microstructure and magnetic properties shows that both concepts have a potential for tailoring the coercivity of Fe 50 Co 50 . [ABSTRACT FROM AUTHOR]

Over the past 15 years, numerous tribological systems for warm and hot aluminium sheet metal forming have been investigated by various researchers. Two previously disregarded aspects will be examined in this paper with an enhanced strip drawing test: the temperature influence on friction and wear performance in an extensive comparison of different lubricant classes in tool lubrication and the bonding performance of different lubricants to the die surface. In depth analyses of the coefficient of friction (COF) and wear performance (wear-free draw-in) for nine different lubricants and additionally several different formulations / mixtures were carried out for sheet temperatures from 20 °C to 425 °C. Furthermore, approaches for future lubricant developments are given. • The flat die strip drawing test resolves detailed lubrication effects of temperature supported sheet metal forming. • Oil-, wax-, polymer- and solid lubricants show distinct behaviours in temperature supported forming of aluminium sheets. • Mixing different lubricant classes can greatly improve overall lubrication performance. • Polymer based bonding agents play a key role in solving tribological challenges of tool lubrication. [ABSTRACT FROM AUTHOR]

Abstract: Workpiece surface topography plays a major role in metal forming processes due to impact on tribology. Especially process feasibility depends directly upon the ability of the tribological system to separate tool and workpiece during the process and realize good lubrication to minimize wear due to shear friction stresses. This paper presents a new approach to describe the surface evolution of workpiece surfaces during cold forging operations. Results can be used to gain knowledge on tribological loads in forming processes and to formulate better friction models since the description takes into account the evolution of the contact area of the contact partners. [Copyright &y& Elsevier]

• The magnetic hardening of Nd-Fe-B cast alloys was achieved by rotary swaging. • Processing by rotary swaging is carried out with a continuous material feed. • A mode for the responsible mechanisms of the microstructural changes is proposed. • Acting state of stresses influence the grain refinement significantly. For the first time, Nd-Fe-B permanent magnets are manufactured by rotary swaging. Nd-Fe-B alloys were heated and deformed by a rotary swaging process with different stress states, degrees of deformation and feed speeds. As a result, the rotary swaged Nd-Fe-B samples were successfully magnetically hardened, which is confirmed by the measurements of magnetic properties with a vibrating sample magnetometer and a pulsed field magnetometer. Microstructures observation by SEM-BSE-EBSD before and after swaging confirmed the drastic grain refinement during the process. The reduction of grain size is attributed to the fracture of grains. The cohesion of the samples is maintained, because the cracks between the fractured grains were immediately filled with the liquid Nd-rich phase. The best swaged sample with a maximum energy product of 8.75 MGOe has a remanence of µ 0 M r = 0.75 T and a coercivity of µ 0 H = 1.05 T. The rotary swaging process enables a continuous manufacturing of Nd-Fe-B permanent magnets directly from castings, which has the potential to be more productive and thus cost-effective in comparison with the conventional powder metallurgical production or hot deformation techniques. [ABSTRACT FROM AUTHOR]

The characterization and modeling of the out-of-plane behavior of fiber-based materials is essential for understanding their mechanical properties and improving their performance in various applications, especially in the forming process. Despite this, research on paper and paperboard has mainly focused on its in-plane behavior rather than its out-of-plane behavior. However, for accurate material characterization and modeling, it is critical to consider the out-of-plane behavior. In particular, delamination occurs during forming processes such as creasing, folding, and deep drawing. In this study, three material models for paperboard are presented: a single all-material continuum model and two composite models using different cohesion methods. The two composite models decouple in-plane and out-of-plane behavior and consist of continuum models describing the behavior of individual layers and cohesive interface models connecting the layers. Material characterization experiments are performed to derive the model parameters and verify the models. The models are validated using three-point bending and bulge tests and show good agreement. A case study is also conducted on the application of the three models in the simulation of a deep drawing process with respect to wrinkle formation. By comparing the simulation results of wrinkle formation in the deep drawing process, the composite models, especially the cohesive interface composite model, show greater accuracy in replicating the experimental results, indicating that a single continuum model can also be used to represent wrinkles.

Collision welding is a promising approach for joining conventional materials in identical or dissimilar combinations without heat-related strength loss, thereby opening up new lightweight potential. Widespread application of this technology is still limited by an insufficient state of knowledge with respect to the underlying joining mechanisms. This paper applies collision welding to a material combination of DC04 steel and EN AW 6016 aluminium alloy. Firstly, the welding process window for the combination is determined by varying the collision speed and the collision angle, the two main influencing variables in collision welding, using a special model test rig. The process window area with the highest shear tensile strength of the welded joint is then determined using shear tensile tests and SEM images of the weld zone. The SEM investigations reveal four distinct metallographic structures in the weld zones, the area fractions of which are determined and correlated with collision angle and shear tensile strength.

In dentistry, the most commonly used implant materials are CP-Titanium Grade 4 and Ti-6Al-4V ELI, possessing comparably high Young's modulus (>100 GPa). In the present study, the second-generation titanium alloy Ti-13Nb-13Zr is investigated with respect to the production of advanced dental implant systems. This should be achieved by the fabrication of long semi-finished bars with high strength and sufficient ductility to allow the automated production of small implants at low Young's modulus (<80 GPa) to minimize stress shielding, bone resorption, and gap formation between the bone and implant. In addition, bacterial colonization is to be reduced, and bone adhesion is to be enhanced by adjusting the microstructure. To do so, a dedicated thermo-mechanical treatment for Ti-13Nb-13Zr has been developed. This includes the adaption of equal channel angular swaging, a modern process of severe plastic deformation to continuously manufacture nanostructured materials, to Ti-13Nb-13Zr and short-time recrystallization and ageing treatments. In particular, two-pass equal channel angular swaging at a deformation temperature of 150°C and a counterpressure of 8 MPa has successfully been used to avoid shear band formation during deformation and to produce long Ti-13Nb-13Zr bars of 8 mm diameter. During recrystallization treatment at 700°C for 10 min followed by water quenching, a sub-micron-size primary α-phase in a matrix of α″-phase was developed. Subsequent ageing at 500°C for 1 h leads to martensite decomposition and, thus, to a homogeneously nanostructured microstructure of α- and β-phase with substructures smaller than 200 nm. The resulting mechanical properties, especially the ultimate tensile strength of more than 990 MPa, fulfill the requirements of ASTM F1713 at Young's modulus of 73 GPa. Biological investigations show promising results in reducing bacterial biofilm formation and increased cell proliferation of osteoblasts compared to CP-Titanium Grade 4 and Ti-6Al-4V ELI, especially, if etched surfaces are applied., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Klinge, Kluy, Spiegel, Siemers, Groche and Coraça-Huber.)

In this paper we present a novel, cost-effective camera-based multi-axis force/torque sensor concept for integration into metallic load-bearing structures. A two-part pattern consisting of a directly incident and mirrored light beam is projected onto the imaging sensor surface. This allows the capturing of 3D displacements, occurring due to structure deformation under load in a single image. The displacement of defined features in size and position can be accurately analyzed and determined through digital image correlation (DIC). Validation on a prototype shows good accuracy of the measurement and a unique identification of all in- and out-of-plane displacement components under multiaxial load. Measurements show a maximum deviation related to the maximum measured values between 2.5% and 4.8% for uniaxial loads (Fx,&nbsp;Fy,Fz,Mz) and between 2.5% and 10.43% for combined bending, torsion and axial load. In the course of the investigations, the measurement inaccuracy was partly attributed to the joint used between the sensor parts and the structure as well as to eccentric load.