Search Results (4)

The surface topography of the rolls used in skin-pass cold rolling determines the surface finish of rolled sheets. In this sense, work rolls can be intentionally textured to produce certain topographical features on the final sheet surface. The maskless electrochemical texturing method (MECT) is a potential candidate for industrial-scale application due to its reduced texturing cost and time when compared to traditional texturing methods. However, there are few studies in the literature that address the MECT method applied to the topography control of cold rolling work rolls. The present work aims to analyze the viability of surface texturing via MECT of work rolls used in skin-pass cold rolling. In this study, we first investigated how texturing occurs for tool steel using flat textured samples to facilitate the understanding of the dissolution mechanisms involved. In this case, a specially designed texturing chamber was built to texture flat samples extracted from an actual work roll. The results indicated that the anodic dissolution involved in tool steel texturing occurs preferentially in the metallic matrix around the primary carbides. Then, we textured a work roll used in pilot-scale rolling tests, which required the development of a special prototype to texture cylindrical surfaces. After texturing, the texture transfer from the work roll to the sheets was investigated. Rolling tests showed that the work roll surface textured with a dimple pattern generated a pillar-shaped texture pattern on the sheet surface, possibly due to a reverse extrusion mechanism. Full article

Skin-pass cold rolling is a crucial step in sheet metal production, modifying the sheet surface topography, ensuring thickness uniformity, and enhancing tribological performance. A key factor in this process is the surface texturing of work rolls, which, when transferred to the rolled sheet, directly affects lubrication distribution and formability in subsequent stamping operations. Properly textured sheets promote lubricant retention, reducing friction and wear, while roll wear can compromise texture transfer, leading to defects in the final product. This review presents a holistic view of surface texturing from the roll topography to the final product. First, it explores different texturing methods for work rolls, analyzing their efficiency, durability, and impact on texture transfer. Then, alternative texturing techniques and coatings are discussed as strategies to mitigate roll wear. By assessing the relationship between roll texturing and sheet drawability, this study provides insights to improve industrial processes, enhance product quality, and promote more sustainable manufacturing solutions. Full article

(1) Objective: Atopic dermatitis (AD) is a recurring skin disease that affects children’s daily activities and sleep quality. Due to the limitations of children’s understanding and ability to express themselves, shared decision making (SDM) is often made by guardians, which thus affects the acceptance and effectiveness of children’s treatments. Previous studies have demonstrated that involving both children and parents in decision making may help improve treatment outcomes; thus, we designed a multimedia mixed reality (MR) interactive game of SDM for children with moderate to severe AD. (2) Methods: Research participants included 6–18-year-old patients with moderate to severe AD. This research consisted of the following steps: designing SDM; character setting and visual design; performing games; system modification and optimization; screen editing and dubbing; and user testing and questionnaires by the System Usability Scale (SUS). (3) Results: We completed the SDM design for children with moderate to severe AD. Four different treatments were biologics, oral immune-modulating drugs, phototherapy, and wet wrap. An animated PowerPoint slide showed the AD apple rolling around before treatments and the AD apple sleeping soundly after treatments. Instructions with video teaching for the four different treatments were played, and then, the MR was turned on so that the patients could help the AD apple in the metaverse to undergo these four treatments. A total of 12 moderate to severe AD patients and six control patients used the game, all aged between six and eighteen years old, with an average SUS score of 81.0 and a standard error of 2.1 points. Adjective ratings yielded a rating between good and excellent. The game showed acceptable usability. We found no statistically significant differences in SUS scores between patients with and without moderate to severe AD or between boys and girls nor significant associations between SUS and age or severity. The analysis identified that the two items with the lowest SUS scores were “I think that I would need the support of a technical person to be able to use this product” and “I needed to learn a lot of things before I could get going with this product”. Both of these comments show the limitations of this game. (4) Conclusions: Overall, this study provides the first MR SDM game that has passed the SUS and can be used as an aid in clinical SDM. Full article

In order to solve the problems of low detection efficiency and safety of artificial surface defects in hot-state cross wedge rolling shaft production line, a machine vision-based method for detecting surface hollow defect of hot-state shafts is proposed. Firstly, by analyzing the high reflective properties of the metal shaft surface, the best lighting method was obtained. And by analyzing the image contrast between image foreground and image background, the most suitable optical filter type in image acquisition was determined. Then, Fourier Gaussian low-pass filtering method is used to remove the interference noise of rolled shafts surface in frequency domain, such as high-light, oxide skin and surface texture. Finally, by analyzing the characteristics of the surface hollow defect area, a defect identification method combining the Otsu threshold method and the adaptive threshold method is proposed to realize the effective extraction of surface hollow defect of rolled shafts. The test results show that the average recognition rate of the method based on machine vision is 95.7%. The results of this paper provide technical support to meet the production requirements of high quality and high performance of cross wedge rolling. Full article