Approccio olistico alla selezione dei materiali nel settore industriale professionale

Materials selection heavily influences the product success on the market and represents one of the factors that contribute in pre-evaluating the performance and impact of each component during the life cycle of the product. The research, in collaboration with the Chemistry, Material and Chemical Engineering Department "Giulio Natta" and Electrolux Professional S.p.A., is applied to the field of professional food processing and laundry appliances and has the aim to develop a versatile materials selection method that could help engineers and designers in evaluating quantitative and qualitative properties of materials. The innovative method wants to overcome the limits of the selection methods currently applied in the field, correlating materials technical properties with the sensorial ones (visual, tactile and auditory). The evaluation of user-interaction aspects with the products would highlight which sensorial properties are involved in the user-experience with the materials the components are made of, and how they influence the quality perception of the product

METAL REPLACEMENT WITH POLYMERS IN PROFESSIONAL FOOD PROCESSING APPLIANCES

Metal replacement is one of the most promising solutions in industrial appliances, both to save money, reduce weight and increase competitiveness on market. Polymers in cooking environments are risky materials if exposed to heat and fire, and flame retardant additives and fire behaviour are key points that has to be considered before replace metals and in general in initial materials selection during appliances project and production

Materials selection for food processing professional appliances

Professional appliances are characterized by an intense use in harsh environments; therefore, they need to communicate, through materials sensorial attributes, robustness and reliability. During their lifetime, professional appliances face specific chemical compatibility problems related to daily contact with food chemicals and detergent compounds compliance, and to misuse practices. These products are developed as tailor-made solutions, designed to satisfy both client needs and usability, even in very specific operative conditions. For this reason, they are developed on one hand through a performance driven technical design process, and on the other through a sensorial oriented materials selection, to improve the user experience with the product. From the Ashby method, the implementation of a flexible materials selection process, able to match sensorial attributes with the real products performances, needs for improvements, due to the highly competitive professional appliances market. The most common design approach in the industrial production of business to business market appliances sees the designer and the engineer as separate figures, which compel respectively to the aesthetical and emotional issues and to the technical and performances requirements. Both these figures operate materials selection with two different perspectives: the lack of communication among the two roles is often due to the different levels of analysis of the process. Electrolux Professional is trying to overcome this limit using an innovative approach, being an appropriate environment to test new solutions. A unique selection method applied to real products, able to couple qualitative and quantitative properties, and to consider both the modification of the technical and chemical properties and the material sensorial perceptions along the products life, can be the driving force of an innovative materials selection approach. The related design process will be then integrated to reach in a unique step a concept that satisfies both the technical performances and the user perception requirements

Materials selection tools in professional appliances: hypothesis to estimate materials’ performance and impact on industrial processes

Concept The use of materials’ selection in professional appliances increased in recent times, thanks to its potential pre-evaluation of materials’ performance and impact on industrial production processes. Through a collaboration among Politecnico di Milano (Department of Design and Department of Chemistry, Materials and Chemical Engineering “Giulio Natta”) and Electrolux Professional S.p.A. (Global Research & Development, Innovation & Technologies Area), an evaluation of materials’ tangible and intangible properties has been developed using non-traditional methods. Among all the currently professional appliances, the oven environment has been chosen as the most emblematic study case. In the first part, this work evidences the major limits and critical points of the materials’ selection tools currently and most commonly proposed in industrial applications. Within these, the main key points highlighted are the translation and connection of quantitative and qualitative properties and the risk associated to the materials selection process reliability. In a second step, some ameliorative hypotheses are built to overcome these limits, using a repeatable and suitable method for different materials selection cases. Motivations and Objectives The research aim is to develop an innovative and versatile method for the materials selection in professional appliances field, used by engineers and designers. From the Ashby [1] and the Karana [2] selection strategies, the non-traditional materials selection methodology would offer a complete evaluation of materials’ tangible and intangible properties. Different variables, indeed, have been taken into consideration: material’s technical properties (e.g. mechanical, thermal and processability parameters), durability (e.g. food chemicals and detergents), food-material compliance and customer perception of properties. The need of a unique materials selection method, able to convert quantitative to qualitative evaluation of properties and to estimate the risk associated to the materials selection reliability, driven the research. A procedure, which evaluates components’ life and possible failure modes (based on DOE and FMEA) [3] [4] [5], is under development in order to integrate these information into the future products development. Results and Discussion The research presents the development of the materials selection methodology under consideration supported by some case studies that focus on durability properties of materials

SMArt Design: un workshop didattico

L’impiego di materiali funzionali nel design spinge verso una progettazione basata sulla possibilità di conferire al prodotto capacità di “sentire” e “reagire”. La diffusione di sistemi smart in oggetti di uso comune sta configurando un nuovo approccio al design: il designer assume i materiali intelligenti come elementi di un linguaggio progettuale che pone al centro l’esperienza soggettiva con il prodotto. Un workshop accademico condotto nella Scuola del Design, del Politecnico di Milano, si è rivelato un’esperienza efficace per avvicinare gli studenti alla conoscenza diretta e concreta delle proprietà di una famiglia di smart materials, le leghe a memoria di forma, ispirando la progettazione di artefatti connessi con utente e ambiente.The use of functional materials in product design opens to the opportunity of giving the artifact the ability to "feel" and "react". The spread of smart systems in everyday objects contributes to the development of a new design approach: the designer assumes smart materials as key elements in the development of an original product design language. Smart materials convey the subjective user-product experience. An educational experience of one-week – conducted at the School of Design, Politecnico di Milano –, demonstrated to be an effective instrument to introduce students to a real and direct knowledge of shape memory alloys’ (SMA) properties. It inspired the design of smart artifacts, connected with the user and the environment

IMPROVING THE LEARNING PROCESS IN MATERIALS SELECTION: THE ROLE OF CONTEXT IN CHOOSING MATERIAL SOLUTIONS

The redesign or incremental innovation of existing products driven by materials selection is a hard process for designers and engineers. Changes on existing design made on one component have to be deeply studied as they are often followed by changes in materials and processing technologies. An educational experience conducted at Politecnico di Milano in collaboration with Innovation & Technologies Department - Electrolux Professional S.p.A., allow students of the course “Materials Selection Criteria In Design & Engineering” (School of Design) to approach this kind of design problems. The structure of the educational experience derived from a previous workshop on materials selection conducted in 2014, in which students worked on lighting products. In the new experience, students focused on materials and technologies of production of some semi-professional cooking appliances. Following the Mike Ashby’s materials selection criteria, students examined a limited number of product’s components, exploring their function, constraints and objectives. The strategy of selection developed by Ashby permits the designer to find different material solutions mainly from the viewpoint of intuitive aspects. Although, applying the method for the first time, students find some difficulties as they are not always able to define function, constraints and objectives for each component they analyze. Moreover, they often misunderstand the difference between “constraints” and “objectives”, confusing the ones of the whole product with the ones of a specific product’s component. This evidence, together with the will to perform a complete investigation of the component under consideration, prompted the development of a tool able to organize the preliminary information that characterize each materials selection, and facilitate the process from the first approach. The “Context Analysis Datasheet” has the aim to clarify the context in which each component operates, increasing the knowledge about the factors that could compromise its functioning. Furthermore, the tool has been developed to facilitate the identification of the limiting factors (constraints) and the objectives of the selection, guiding the process of materials and manufacturing technologies selection. This paper shows the results of the first application of the “Context Analysis Datasheet” in an educational experience. Analyzing the users’ feedback, and assessing the strengths and the weaknesses of the tool, concrete guidelines would be proposed

VISUAL EXAMINATION OF METAL-LOOK FINISHES STABILITY AFTER ACCELERATED AGING TEST ON POLYMERIC COMPOSITES APPLIED IN THE PROFESSIONAL KITCHEN ENVIRONMENT

Introduction: In the professional appliance industry, materials selection for metal replacement represents an opportunity for the design of the components characterized by manual interaction with the user. It allows, indeed, to fulfill ergonomic design and safety requirements (e.g., electrical and thermal insulation). Although, as professional appliances are characterized by an intense use in harsh environments, the materials and finishes’ durability in time have to be studied. Materials and methods: Polymer samples, characterized by six different metal-look finishes, have been prepared by accelerated aging. The samples were exposed to temperature and the most present chemical solutions in the professional kitchen environment (5 food chemicals and 4 surface cleaners). The stainless steel-look finishes that were selected, were developed by bulk-technology, water transfer printing, painting, and aluminum and stainless steel PVD coating. Results: A visual evaluation of the finishes colour alteration was performed, both by spectrophotometric analysis (Konica Minolta CM-2600d) and stereomicroscopy (Leica model M165 C). One metal-look painting finishing (Z), already applied in the professional kitchen environment, was used as the reference sample. The analysis showed that the highest values in ΔE (colour variation) was registered in the case of PA composite coated by water transfer printing (C) (38.978) and by aluminium PVD (S) (30.938), both immersed in vinegar solution. Chlorine monofluoride demonstrated to be the most aggressive surface detergent solution regarding both C sample (34.707) and S sample (34.960). The same solution sensibly interacted also with the ABS painted sample (R) (21.876). Discussion: On the basis of the data collected by the experimental tests, we can conclude that some finishes exhibit an evident chemical incompatibility with the chemical solutions present in a professional kitchen environment. PVD coated Aluminium and water transfer printed PA composite samples have been significantly degraded by both surface cleaners and food chemicals, in particular by vinegar and chlorine monofluoride. Moreover, some colour alterations were detected also on painted samples, when tested with some detergents. Further studies at different aging conditions (time, temperature, chemical solution) should be conducted to examine the degradation of composites materials and finishes in such environment