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This article presents an experimental study of the material extrusion process to examine the impact of less-analyzed factors on surface roughness, not including the commonly known layer height. The study also gives attention to the inner surfaces of printed samples. The design of experiments used a fractional factorial design with five two-level factors: bed temperature, fan percentage, printing speed, printing temperature, and wall thickness. Thus, the purpose of the design is screening. A two-dimensional contact profilometer was used to measure the surface roughness. Generally, the inner faces of the printed samples showed lower surface roughness. In addition, four analysis of variance showed that wall thickness (for Raand Rz) and printing speed (for Ra) are significant for the outer and inner surfaces, respectively. As the wall thickness increased, the surface roughness decreased. Meanwhile, the lower the printing speed, the worse the surface quality on the inner faces.

Nephrogenic adenoma (NA) is an infrequent reactive urothelial lesion. The expression of immunohistochemical renal tubular markers has been reported in NA, although a proximal or distal nephron phenotype has not been established. Special AT-rich sequence-binding protein 2 (SATB2) is a marker of a colorectal origin of adenocarcinomas, occasionally reported in renal samples. We have analyzed SATB2 expression in NA, with correlation with other tubular markers, as well as in the normal kidney. Fifty cases of NA were immunostained with PAX8, SATB2, proximal nephron markers [CD10, renal cell carcinoma (RCC) marker, alpha-methylacyl-CoA racemase (AMACR), and CD15], and distal markers (Ksp cadherin, cytokeratin 7, E-cadherin (E-cad), and cytokeratin 19). Ten normal kidney sections were stained with a double method combining SATB2 plus CD10, RCC marker, AMACR, Ksp cadherin, cytokeratin 7, or E-cad. All NA were immunoreactive for PAX8 and 57% for SATB2. Every case was positive for proximal and distal nephron markers: 100% for cytokeratins 7 and 19, 84.1% E-cad +, 81.6% AMACR +, 68.9% Ksp cadherin +, 63% CD15 +, 53.3% CD10 +, and 28.6 % RCC +. In the normal kidney, SATB2 was detected in the straight part of the proximal tubules and the thin descending loops of Henle. NA shows a multiphenotypic pattern with coexpression of both proximal and distal nephron markers, and constant expression of PAX8, cytokeratins 7 and 19. SATB2 is often positive in NA, which should be kept in mind to avoid a possible misdiagnosis of intestinal adenocarcinoma. SATB2 is a marker of the normal proximal nephron.

We conducted an integral study based on micromagnetic simulations and experiments to systematically investigate the quasi-static and dynamic magnetic characteristics of CoxNi100–xnanodots, varying the Co composition. We compared the magnetic properties of both ideal and real defective circular geometries, employing phase diagrams, hysteresis loops, and magnetization reversal modes for a comprehensive analysis. Our study highlights distinct alterations in coercivity and remanence between ideal and real defective geometries, while the S-mode of reversal is observed in both cases. Notably, our simulations underscore the remarkable sensitivity of magnetic properties to edge defects and the Co content in the alloy. This research underscores the essential role of micromagnetic simulations in tailoring the Co composition of the alloy, thereby fine-tuning the material’s magnetic hardness for enhanced performance in electrochemical applications, particularly as electrodes in energy storage devices.

Abstract

The main objective of this work was to study the influence of the injection moulding process on the tribological behaviour of ABS polymers and nylon PA6.6+15% of glass fibres. The article also describes the structure of wear maps. Its topic is the preservation of the initial surface roughness at the bottom of the track in tribotesting. Testing and measurement methodologies and data processing techniques are described. ABS and PA6.6+15%GF are polymers. Their specifications state that they are both thermoplastics with very similar characteristics. Tribotesting was employed to find whether or not this is the case. The pin-on-disc method was used to obtain the data. As a summary of the experiment was created wear map that describes the behavior of the material with various input test conditions. During subsequent analysis of this map were discovered not correlating areas that were undergone to further investigation. During this investigation an unknown inclusions in the structure were revealed which are now subjected to further investigation.

The wear of TiCN coating carbide cutting tools (Sandvik® Grade 1010 and 4220) in different hard-milling machining conditions was monitored, analyzed, and discussed for AISI H13 steel. This material is commonly used in the forge industry in order to optimize the manufacturing process according to a qualimetry/cost compromise criterion. AISI H13 steel generally is used in modern production for high wear-resistant dies and molds. One of the most basic and primary geometric shapes in the manufacture of molds and die cavities is the geometry known as "inclined plane." Experimental investigations were carried out on a "mold model" design with the aim of analyzing and optimizing the principal manufacturing conditions. The tests are dependent on manufacturing factors, particularly their impactin a complex tribological process. Five clearly defined different surfaces of the hardened AISI H13 steel model mold, with appropriate geometries were studied; i) vertical downward; ii) curved downward; iii) horizontal; iv) curved upward; and v) vertical upward.The analysis of cutting tool wear during this process was based on computerized measurements of visually observable wear and power consumption. Morphological investigations of the surface topography for the cutting tool, as well as of the work-piece surfaces, were systematically carried out. Moreover, the interactions with simultaneously measured energy consumption during the process are also explicated in the present study and therefore tentative methods to optimize hard-milling machining are offered.

The main objective of this research is study the wear of a mould, made in easy machining material; aluminium EN AW-6082 T4 and the surface characterization of mould cavity, used in a polymeric manufacturing process, after several injection cycles. To evaluate the effectiveness of this materials in the plastic injection process, a test part with different thicknesses and shapes was designed and some inserts of aluminium were made. In the way of plastic material, a 30 % fiberglass reinforced polyamide PA6 has been employed in the experimental procedure. A reusable injection mould was used and surface measurements of mould cavity have been performed after 9200 cycles. The surface topography has been measured by using optical interferometry profiling technology and there have also been obtained roughness and surface parameters according to ISO 25178 and EUR15178N. In order to surface characterization, different areas of the mould cavity with different geometries, has been analysed. The behaviour of wear rate has been analysed by the study of the evolution of the surface parameters and functional parameters in different points of the surface mould.