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The effect of high-temperature processing on laser clad Ni-based coatings is studied. Annealing at 1025°C forms thermally stable framework structures with large chromium carbides and borides. As a result, improved hardness and wear resistance of the coating are maintained when heated to 1000°C. Stabilizing annealing also increases the frictional thermal resistance of the NiCrBSi coating. Under high-speed (3.1– 9.3 m/s) sliding friction, when the surface layer temperature reaches about 500 –1000°С and higher, the wear resistance of the coating increases by 1.7 – 3.0 times. The proposed approach to the formation of heat-resistant coatings is promising, in particular, for a hot deformation tool and other components of metallurgical equipment operating under high thermal and mechanical loads. Such products include crystallizer walls of continuous casting machines. For the walls, the development of laser cladding technology for wear-resistant composite coatings on copper alloys is relevant as an alternative to thermal spraying. The cladding of composite NiBSi-WC coatings of 0.6 and 1.6 mm thickness on a Cu-Cr-Zr bronze substrate heated to 200 – 250°C with a diode laser is considered. The presence of boron causes the formation of the W(C, B) carboboride phase, whose hardness is higher than that of WC in the initial powder. Depending on the thickness of coatings and, accordingly, on the duration of heating and the subsequent cooling, the process of secondary carboborides precipitation from the solid solution can be suppressed (in the “thin” coating) or activated (in the “thick” coating). This leads to a higher wear resistance under friction sliding 1.6 mm thickness coating. © 2019, Institute for Metals Superplasticity Problems of Russian Academy of Sciences. All rights reserved.

Cláudia Maria Vilas Freire1,2, Antonio Luiz Pinho Ribeiro1, Felipe Batista Lima Barbosa1, Anelise Impelisiere Nogueira1, Maria Cristina Costa de Almeida1,2, Márcia Melo Barbosa2, Ângela Maria Quintão Lana3, Ana Cristina Simões e Silva4, Antônio Ribeiro-Oliveira Jr11Department of Internal Medicine, School of Medicine, 3Statistics Laboratory, Veterinary Department, 4Department of Pediatrics, School of Medicine, Federal University of Minas Gerais (UFMG), Belo Horizonte, MG, Brazil; 2Ecocenter, Hospital Socor, Belo Horizonte, MG, BrazilBackground and aim: The measurement of carotid intima-media thickness (cIMT) has been used as a marker of arterial wall disease. Manual measurements have been performed in most epidemiological studies, but, due to the introduction of new technologies, automated software has been increasingly used. This study aimed to compare manual versus automated cIMT measurements in common carotid (CC), bifurcation (BIF), and internal carotid (IC).Methods: Automated and manual cIMT measurements were performed online in 43 middle-aged females. Carotid segment measurements were compared by Bland–Altman plot and the variation and repeatability coefficients between observers were also determined for comparison.Results: The average timespan for manual measurements (57.30 s) were significantly higher than for automated measurements (2.52 s). There were no systematic errors between methods in any carotid segments. The variation coefficient was 5.54% to 6.34% for CC and BIF, 9.76% for IC, and absolute differences were 85% below 0.1 mm and 70% below 0.05 mm. Interobserver agreement showed no systematic error. The variation and the repeatability coefficients were better for the automated than manual measures.Conclusion: Although both methods are reliable for cIMT measurements, the automated technique allows faster evaluation with lesser variability for all carotid segments currently used i