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Binder jetting is a promising route to produce complex copper components for electronic/thermal applications. This paper aims to lay a framework for determining the effects of sintering parameters on the final microstructure of copper parts fabricated through binder jetting.

The knowledge gained from well-established powder metallurgy processes was leveraged to study the densification behaviour of a fine high-purity copper powder (D₅₀ of 3.4 µm) processed via binder jetting, by performing dilatometry and microstructural characterization. The effects of sintering parameters on densification of samples obtained with a commercial water-based binder were also explored.

Sintering started at lower temperature in cold-pressed (∼680 °C) than in binder jetted parts (∼900 °C), because the strain energy introduced by powder compression reduces the sintering activation energy. Vacuum sintering promoted pore closure, resulting in greater and more uniform densification than sintering in argon, as argon pressure stabilizes the residual porosity. About 6.9% residual porosity was obtained with air sintering in the presence of graphite, promoting solid-state diffusion by copper oxide reduction.

This paper reports the first systematic characterization of the thermal events occurring during solid-state sintering of high-purity copper under different atmospheres. The results can be used to optimize the sintering parameters for the manufacturing of complex copper components through binder jetting.

This study aims at compensating for sintering deformation of components manufactured by metal binder jetting (MBJ) technology.

In the present research, numerical simulations are used to predict sintering deformation. Subsequently, an algorithm is developed to counteract the deformations, and the compensated deformations are morphed into a CAD model for printing. Several test cases are designed, compensated and manufactured to evaluate the accuracy of the compensation calculations. A consistent accuracy measurement method is developed for both green and sintered parts. The final sintered parts are compared with the desired final shape, and the accuracy of the model is discussed. Furthermore, the effect of initial assumptions in the calculations, including green part densities, and green part dimensions on the final dimensional accuracy are studied.

The proposed computational framework can compensate for the sintering deformations with acceptable accuracy, especially in the directions, for which the used material model has been calibrated. The precise assumption of green part density values is important for the accuracy of compensation calculations. For achieving tighter dimensional accuracy, green part dimensions should be incorporated into the computational framework.

Several studies have already predicted sintering deformations using numerical methods for MBJ parts. However, very little research has been dedicated to the compensation of sintering deformations with numerical simulations, and to the best of the best of the authors' knowledge, no previous work has studied the effect of green part properties on dimensional accuracy of compensation calculations. This paper introduces a method to omit or minimize the trial-and-error experiments and leads to the manufacturing of dimensionally accurate geometries.

The key purpose of conducting this review is to identify the issues that affect the structural integrity of pipeline structures. Heat affected zone (HAZ) has been identified as the weak zone in pipeline welds which is prone to have immature failures

In the present work, literature review is conducted on key issues related to the structural integrity of pipeline steel welds. Mechanical and microstructural transformations that take place during welding have been systematically reviewed in the present review paper.

Key findings of the present review underline the role of brittle microstructure phases, and hard secondary particles present in the matrix are responsible for intergranular and intragranular cracks.

The research limitations of the present review are new material characterization techniques that are not available in developing countries.

The practical limitations are new test methodologies and associated cost.

The fracture of pipelines significantly affects the surrounding ecology. The continuous spillage of oil pollutes the land and water of the surroundings.

The present review contains recent and past studies conducted on welded pipeline steel structures. The systematic analysis of studies conducted so far highlights various bottlenecks of the welding methods.

As an optimal microstructure of pipeline steels, acicular ferrite is widely found in steels used in oil and gas pipeline transportation because it possesses both high strength and good toughness. In this paper, the microstructure of acicular ferrite and its continuous cooling transformation (CCT) diagrams of six steels with different carbon and alloy additions have been studied by using dilatometry, optical metallography. And the effects of different hot deformation processes on the CCT diagrams and microstructures have also been studied. Furthermore, the effects of microalloyed elements and hot deformation on continuous cooling transformation have been discussed. The results show that lower carbon content and alloy additions such as Mn, Nb, Ti, Mo, Ni and/or Cu in steels will promote the formation of acicular ferrite. The hot deformation promotes the acicular ferrite transformation and refines the microstructures of final products.

The mechanical properties of eight solder alloys from the Pb‐Sn‐In‐Ag alloy systems were determined over the temperature range ‐200°C to 100°C, using uniaxial tensile tests, dynamic mechanical analysis (DMA), acoustic pulse methods and dilatometry. In general, the strength and elastic modulus of the alloys studied was inversely dependent on temperature. PbSn, PbIn and SnIn alloys were observed to turn superplastic with elongations over 100 per cent at temperatures of 50°C or above. The Pb‐based and In‐Sn eutectic solders possessed superplasticity at temperatures greater than 50°C. From these results, deformation and fracture processes are reviewed, and the appropriate fracture mechanism is proposed.

The purpose of this paper is the microstructural and mechanical characterization of a biomedical Ti‐6Al‐4V alloy produced by electron beam melting, and the study of the stability of the as‐built microstructure upon heat treatment.

Ti‐6Al‐4V alloy produced by electron beam melting has been mechanically characterized through tensile and fatigue testing. Its microstructure has been investigated by optical observation after etching and by X‐ray diffractometry analysis. The stability of the microstructure of the as‐built material has been deepened carrying out suitable heat treatments, after an analysis by dilatometry test.

The microstructure of a Ti‐6Al‐4V alloy produced by electron beam melting has a very fine and acicular morphology, because of the intrinsically high‐solidification rate of the process. This microstructure is very stable, and the traditional thermal treatments cannot modify it; the microstructure changes significantly only when an amount of strain is introduced in the material. However, the mechanical properties of the alloy produced by electron beam melting are good.

The paper provides evidence of the microstructural stability of the material produced by electron beam melting. Even if the microstructure of the as‐built material is not recommended by the specific ISO standard, the related mechanical properties are fully satisfactory. This is a significant indication from the point of view of the production of Ti‐6Al‐4V orthopaedic and dental prostheses by electron beam melting.

In the food, drink, and pharmaceutical industries, ultrasonic sensors have advantages over many existing devices. They are capable of rapid, precise measurements and can be fully automated. Also, they can be used online, applied to optically opaque systems, and, moreover, are very cost‐effective.

An evaluation programme involving the extensive thermal cycling of component‐assembled printed circuit boards has been undertaken to assess the suitability of ESA‐approved hand‐soldering techniques for use on long‐life satellites. The modes of joint degradation are discussed and the metallurgical changes that result from material thermal expansion mismatch and repeated strain within the solder alloy (63% tin, 37% lead) are highlighted by photomicroscopy.

The purpose of this work is to determine the induction hardening behavior of a new steel composition. For this purpose, Flux2D commercial software together with a Gleeble thermomechanical simulator has been used to numerically and physically simulate the material properties profile of an induction hardened slurry transportation pipe made of a recently developed 0.4 Wt.% C, Nb-microalloyed steel.

Flux 2D commercial software together with a Gleeble thermomechanical simulator machine has been used to predict the induction behavior of the studied material. After calculating the thermal history of a 400 mm diameter, 10 mm thick pipe at various positions through the thickness, different heating and cooling paths were physically simulated using the Gleeble machine to predict the through thickness material microstructure and hardness profiles.

The results showed that by coupling a phase transformation model considering the effect of heating rate on the austenite transformation temperatures which allows calculations for arbitrary cooling paths with calculated induction heating and quenching thermal cycles, it has been possible to design induction hardening parameters for a slurry transport pipe material.

The composition used in this research as well as the methodology approach is designed at this work.

A superconducting material with a composition Y1−xBa2Cu3O7−3/2x − x/2 Bi2O3 (x = 0·1 and 0·2) was synthesised. The influence of Bi2O3 additions on sintering was studied. Preliminary investigations of the Bi‐Sr‐Ca‐Cu‐O system were also made. Thick film pastes, prepared from Y1−xBixBa2Cu3O7 compositions, from the compound YBa2Cu3O7 with 10 w/o addition of Bi2CuO4 and from two compositions in the Bi‐Sr‐Ca‐Cu‐0 system, were fired on Al2O3 and ZrO2 substrates. All thick film materials based on YBa2Cu3O7 compound were superconducting at temperatures above 77 K when fired on ZrO2 substrates, while only a material with the starting composition Y0·8Ba2Cu3O6.7 − 0·1 Bi2O3 reached zero resistivity above 77 K on Al2O3 substrates. Tc (onset) of samples based on the YBa2Cu3O7 compound was around 95 K, and of samples from the Bi‐Sr‐Ca‐Cu‐O system between 95 and 100 K.