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Feasibility, acceptability and effectiveness data of a virtual adaptation of the WHO Caregiver Skills Training (CST; n = 25) were compared with those of a pilot RCT of CST delivered in person (n = 43) against treatment as usual (TAU; n = 43). Virtual CST was delivered with high levels of integrity, but received lower ratings in some caregiver- and facilitator-rated acceptability and feasibility dimensions. Qualitative analysis identified both benefits (flexibility, convenience, clinical usefulness) and challenges, (technological issues, distraction from family members, emotional distance). Virtual and in-person CST improved significantly more on caregiver competence than TAU; there were no other significant effects. Potential for use of virtual CST as a clinical response in contexts where in-person delivery is not possible is discussed.

Metal matrix composites (MMCs) show enhanced mechanical and physical properties compared to monolithic alloys, which make them attractive for various engineering applications. However, their actual use in industry is limited due to their low machinability. The hard reinforcements present in the matrix may lead to high tool wear and poor surface integrity. In this context, the paper aims at studying the drillability of an Al-SiC MMC when using DLC-coated tungsten carbide tools at varying feeds. After the machining trials, a quantitative evaluation of the tool wear as well as the analysis of the hole surface roughness and damage was carried out. The results demonstrate that, at increasing feed, the tool wear, surface roughness, and surface defect density decrease, leading to the counterintuitive conclusion that increasing feed when drilling causes an increase in the MMC drillability. [ABSTRACT FROM AUTHOR]

Plastic syringes often rely on silicone oil lubrication to reduce plunger-barrel friction, leading to potential issues like oil droplet release and drug aggregation. This study explored an alternative approach combining two-photon polymerization, laser machining, and microinjection molding to manufacture micro-dimpled structures for low friction. Plastic microdimples with high area density and low aspect ratio significantly reduced the coefficient of friction against rubber, while the dimple profile proved crucial in facilitating replication and demolding. The results of this study provide valuable insights into reducing friction between rubber and plastic, particularly in applications like syringes. [ABSTRACT FROM AUTHOR]

Thermoplastic fibre metal laminates (FMLs) increasingly attract attention in manufacturing parts that must present high strength-to-weight and stiffness-to-weight ratios. In addition, their polymer matrix's recyclability meets sustainability needs that conventional thermosetting-based FMLs cannot encounter. Mechanical drilling is one of the most used manufacturing operations they are subjected to, but it can still be a source of damage in the drilled zone, which, in turn, can impair the part service performance. In particular, the interface conditions between the metal skins and composite core significantly determine the drilling performance. In this framework, the paper investigates how the metal sheet surface modification treatments and composite polymer matrix characteristics can affect the drilling operation performance. It has been proved that rough metal surfaces and a polymer matrix with enhanced thermal resistance are the best combinations to ensure the integrity and quality of drilled holes. [ABSTRACT FROM AUTHOR]

Surface nanopatterning of plastic parts is a promising solution to enable the mass production of bactericidal applications without using antibiotics. In this work, an innovative process chain for efficiently manufacturing bactericidal parts was developed and validated. It is based on a particular type of laser-induced periodic surface structuring of injection molds that can be effectively replicated onto size-tunable bactericidal nanopatterns. Their polyvalent bactericidal performance directly correlates with the surface feature parameters Shh, Spd , and Spc , showing that higher, denser, and sharper spikes are more effective in killing bacteria by perforating their membrane. [ABSTRACT FROM AUTHOR]

Laser direct energy deposition is commonly used to improve the surface properties of poorly resistant materials, repair worn portions, or change the shape of a component. In this paper, C45 steel substrates were laser deposited with multiple layers of grade 300 maraging steel. Micromilling operations were then carried out on the laser depositions both in as-built and heat-treated conditions to improve the surface integrity. The cutting forces were measured at varying cutting directions. An in-depth characterization of the surface integrity induced by micromilling was conducted, considering microstructural features, microhardness, surface topography, and surface defects. The results proved that the laser deposition-induced anisotropy had a remarkable influence on the laser deposited material machinability and must be taken into account. [ABSTRACT FROM AUTHOR]

The paper proposes the prediction of the fatigue strength of additive manufactured Ti6Al4V titanium alloy machined under flood and cryogenic cooling conditions, making use of the approach based on linear elastic fracture mechanics that was used for the first time in the context of such process chains. The role of the machining-generated surface texture, hardening, microstructural characteristics and residual stresses states is discussed in detail, giving new insights about the correlation between surface integrity and fatigue strength when addressing defective metal alloys, as those fabricated through AM. [ABSTRACT FROM AUTHOR]

• The laser cladding quality is more affected by the scanning speed and the powder granulometry rather than the laser power. • Decreasing the number of laser cladding layers improves the cladding quality, but worsens the machinability. • The intrinsic presence of the tempering bands reflects on the machined surface topography. Laser cladding followed by machining is nowadays a process chain widely utilized in the metal manufacturing industry for restoration of high-value components and optimization of the mechanical and corrosion properties of poorly performant alloys. In this paper, C45 steel substrates were laser cladded with multiple layers of AISI H13 tool steel. First, the powder granulometry, scanning speed, and laser power were varied to obtain homogeneous and fully dense claddings with high hardness. The number of deposited layers was then varied using the optimized laser cladding parameters and its effect on the claddings quality was assessed both in the as-built and machined conditions. A detailed characterization was carried out considering macrostructural and microstructural features, porosity, and microhardness, taking into consideration also geometrical and topographical characteristics. This study shows, for the first time, a robust correlation between the number of layers and the cladding characteristics both before and after machining. In particular, a reduced number of layers was proved to lead to a better quality of the as-built claddings, but negatively affects their machinability. [ABSTRACT FROM AUTHOR]

This work investigates the machinability characteristics of additively manufactured Ti6Al4V titanium alloy workpieces in finishing machining using ball end mills on 45° inclined surfaces. The surface finish results were compared with the ones from ball end milling trials on wrought Ti6Al4V samples using the same cutting conditions. Optical profilometry and scanning electron microscope imaging were used to compare the different surface texture and quality of the two alloys, as well as the chip morphology, with the aim of finding a correlation between the surface finish obtained at varying cutting parameters and the Ti6Al4V peculiar microstructure induced by the additive manufacturing process. The results showed that the additively manufactured alloy allowed for a better surface quality respect to the wrought one. This was attributed to the interactions of the ball mill cutting edge with the α phase colonies of such alloy, which may favor the material removal by locally lowering the material resistance to cutting. [ABSTRACT FROM AUTHOR]

Final machining steps are commonly requested on parts obtained via additive manufacturing to ensure the required surface finish and geometrical tolerances. When machining additive manufactured workpieces, their typical microstructural anisotropy is rarely taken into consideration. In this work, the influence of the build-up orientation of Ti6Al4V parts obtained via laser powder bed fusion on machinability is studied. Ti6Al4V blocks with horizontal and vertical development were additively manufactured and then milled. Tool wear progression was monitored and its effect on surface quality investigated. The cutting tool that machined the horizontally oriented sample showed a tool life 66% higher than the one that machined the vertically oriented one. This study demonstrates the strong correlation between the build-up orientation of additive manufactured components and their machining response. [ABSTRACT FROM AUTHOR]