Analysis of Different Tool Path Strategies for Free Form Machining with Computer Aided Surface Milling Operations

[EN] Free form surfaces are commonly used to generate aesthetic parts. These parts can be manufactured directly by material removal techniques or indirectly with molding or forming techniques. In any case, these surfaces must be commonly machined with traditional processes, at least until certain degree of surface finishing, and the tool path must be generated with computer aided applications. In doing so, developers are implementing new theoretical strategy operations for controlling tool path and trajectories. These new options have so many combinations that it is difficult to know which is the best one to choose when defining the tool movements. Apart from the traditional strategies fixed angle method, principal axis method and multipoint machining, combined with tool orientation, there are many other strategies to explore due to machine tool and numerical control improvements. What is need now is a validation of these new strategies in computer aided applications regarding time minimizing and how the cutting parameters affects in the surface final result.The authors would like to thanks Universitat Politècnica de València, La Fondation Dassault Systèmes, Carolina Foundation and the National Polytechnic School for the support of this article through the 2017 call and project PIS 16-15 - PIS 16-22.Vila, C.; Ayabaca-Sarria, C.; Torres Carot, R.; Gutiérrez, SC.; Meseguer, M.; Yang, X. (2019). Analysis of Different Tool Path Strategies for Free Form Machining with Computer Aided Surface Milling Operations. Procedia Manufacturing. 41:843-850. https://doi.org/10.1016/j.promfg.2019.10.006S8438504

ENFRENTAMENTO DA PROBLEMÁTICA DO CÂNCER DE MAMA NA ESTRATÉGIA DA SAÚDE DA FAMÍLIA

Breast cancer stands as one of the principal causes of morbidity and mortality among women worldwide, including in Brazil. The Family Health Strategy (FHS) plays a pivotal role in the prevention, early detection, and treatment of this ailment, given its integration into primary care with the overarching goal of providing comprehensive care and promoting health. This study aims to scrutinize how the FHS addresses the issue of breast cancer, with a particular focus on prevention, early diagnosis, and treatment, through an integrative literature review. In this study, we opted for the integrative literature review methodology to comprehend the strategies employed by the Family Health Strategy in coping with breast cancer. The integrative literature review revealed that the Family Health Strategy assumes a pivotal role in confronting the issue of breast cancer. Key strategies include the conduct of awareness campaigns, the promotion of mammography and self-examination, the training of healthcare professionals, and coordination with medium and high-complexity services to ensure access to treatment.O câncer de mama é uma das principais causas de morbidade e mortalidade entre as mulheres em todo o mundo, incluindo o Brasil. A Estratégia de Saúde da Família (ESF) desempenha um papel fundamental na prevenção, detecção precoce e tratamento dessa doença, visto que está inserida na atenção básica e tem como objetivo promover o cuidado integral e a promoção da saúde. Este estudo tem como objetivo analisar como a ESF enfrenta a problemática do câncer de mama, com foco na prevenção, diagnóstico precoce e tratamento, através de uma revisão integrativa da literatura.  Neste estudo, optou-se por utilizar a metodologia da revisão integrativa da literatura para compreender as estratégias de enfrentamento do câncer de mama pela Estratégia de Saúde da Família (ESF). A revisão integrativa da literatura revelou que a Estratégia de Saúde da Família desempenha um papel fundamental no enfrentamento da problemática do câncer de mama. Dentre as principais estratégias adotadas, destacam-se a realização de campanhas de conscientização, a promoção da mamografia e do autoexame, a capacitação dos profissionais de saúde, e a articulação com serviços de média e alta complexidade para garantir o acesso ao tratamento

Study of machining strategies for minimizing vibration in the milling of convex surfaces

Orientador: Anselmo Eduardo DinizTese (doutorado) Universidade Estadual de Campinas, Faculdade de Engenharia MecânicaResumo: A fabricação de moldes e matrizes requer o fresamento de superfícies complexas de aço endurecido. Normalmente, as cavidades profundas destas peças são cortadas utilizando tecnologias de usinagem em altas velocidades e ferramentas com grande relação comprimento/diâmetro. Sendo assim, a fresa tem uma alta tendência de vibrar e danificar a superfície da peça, além de poder sofrer lascamento ou quebra. Este trabalho buscou verificar a vida da ferramenta, as forças de corte e rugosidade da peça no fresamento de topo de uma superfície curva, convexa, de aço ferramenta AISI D6 com dureza de 62 HRC, utilizando uma fresa de topo esférico. O objetivo do trabalho foi encontrar condições que proporcionassem uma boa qualidade de superfície com vida longa da ferramenta de corte. O trabalho foi dividido em três etapas de experimentos. Os resultados da primeira etapa de testes mostraram que na usinagem de superfícies convexas com direção de avanço seguindo uma trajetória circular a rugosidade da peça e os esforços de corte são fortemente influenciados pelo sentido de usinagem, sendo que o corte descendente proporcionou melhor rugosidade e menores esforços radiais. Na segunda etapa de testes, quando se usinou com direção de avanço seguindo uma trajetória linear (passes com coordenada Z constante) utilizando três lead angles diferentes (-16°, 0° e 16°), os menores valores de rugosidade e menores esforços de corte foram obtidos com estratégia ascendente e lead angle de 0°. Na terceira etapa foi avaliada a vida das ferramentas nas condições testadas na segunda etapa. A análise de variância foi realizada para entender melhor os resultados. Os resultados mostram uma estreita relação entre a componente radial da força de usinagem (que provoca flexão da fresa e consequentemente vibração), a rugosidade e a vida da ferramenta. As condições de corte que proporcionaram a menor força radial também geraram melhor rugosidade e maior vida da ferramenta. Adesão seguida de lascamento da aresta de corte foi o principal mecanismo de desgaste verificadoAbstract: The manufacture of molds and dies involves the milling of complex surfaces of hardened steel. Typically, the deep cavities of such parts are cut using high-speed machining technologies and tools with a high length/diameter ratio. Thus, the milling cutter has a high tendency to vibrate, which may result in cutting edge chipping and/or breakage, and it may also damage the workpiece surface. This work analyzed the tool life, cutting forces and surface roughness in the ball-end milling of a curved (convex) surface of AISI D6 tool steel with hardness of 62 HRC. The goal was to find conditions that provide a good surface quality with long tool life. The work was divided into three stages of experiments. The results of the first stage showed that when machining convex surfaces with the feed direction following a circular path (upward or downward), the roughness and cutting forces are strongly influenced by the feed direction, and a downward strategy provided the best roughness and the smallest cutting forces. In the second stage of testing, when the feed direction followed a linear path (passes with constant Z coordinate) using three different lead angles (-16°, 0° and 16°), the best roughness and the smallest cutting forces were obtained with an upward strategy and lead angle of 0°. In the third stage we evaluated the tool life under the conditions tested in the second stage. Analysis of variance was used for a better understanding of the results. The results showed a close relationship between radial component of the machining force and surface roughness and tool life. The cutting conditions that provided the smallest radial force also generated the best surface finish and longest tool life. Attrition followed by chipping of the cutting edge was the main wear mechanismDoutoradoMateriais e Processos de FabricaçãoDoutor em Engenharia Mecânica2012/20816-2FAPES

Tool Life And Surface Roughness In The Milling Of Curved Hardened-steel Surfaces

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)The manufacturing of molds and dies requires that complex hardened-steel surfaces be milled. The deep cavities in these parts are generally cut using high-speed machining technologies and long, slender tools. Consequently, the milling cutter has a tendency to vibrate, potentially damaging the surface of the workpiece and causing the cutting tool to chip or break. This study investigates tool life, cutting forces, and surface roughness in ball-end milling of a curved, convex surface of AISI D6 tool steel with a hardness of 62 HRC. The main goal was to find cutting conditions that provide good surface quality with long tool life. Two cutting strategies (upward and downward) with three lead angles (-16A degrees, 0A degrees, and 16A degrees) were tested. Analysis of variance was used to understand the results better. Adhesion followed by chipping of the cutting edge was the main wear mechanism found. The results show a close relationship between radial components of the machining forces and surface roughness and tool life. The cutting conditions that provided the lowest radial force also generated the best surface finish and the longest tool life (an upward strategy with a lead angle of 0A degrees).879-1229832995FAPESP (Sao Paulo Research Foundation, Brazil) [2012/20816-2, 2013/00551-7]Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

The Influence Of Cutting Forces On Surface Roughness In The Milling Of Curved Hardened Steel Surfaces

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)The milling of dies and molds involves the machining of complex shapes from hardened steel. To allow deep cavities to be manufactured, milling cutters are usually long with a small diameter. Because of this and because of the cutting forces involved, they have a tendency to vibrate. In finishing operations, vibration is more critical as it can damage the surface quality of the die or mold, affecting end-product quality. Determining the components of the cutting forces may therefore help choose milling parameters that reduce surface roughness. In light of this, the present work seeks to provide a better understanding of the influence of milling parameters on cutting forces and surface finish when milling dies and molds. Milling tests were performed to investigate the effects of cutting strategy, lead angle and tool overhang (input variables) on cutting force components, and workpiece surface roughness (output variables). The results were evaluated by analysis of variance. The main conclusion was that surface roughness is directly related to radial force and that the cutting conditions that provided the lowest radial load (an upward strategy with a lead angle of 0 degrees) produced the best surface roughness.845-812091218FAPESP (Sao Paulo Research Foundation, Brazil) [2012/20816-2, 2013/00551-7]Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

The influence of cutting forces on surface roughness in the milling of curved hardened steel surfaces

The milling of dies and molds involves the machining of complex shapes from hardened steel. To allow deep cavities to be manufactured, milling cutters are usually long with a small diameter. Because of this and because of the cutting forces involved, they have a tendency to vibrate. In finishing operations, vibration is more critical as it can damage the surface quality of the die or mold, affecting end-product quality. Determining the components of the cutting forces may therefore help choose milling parameters that reduce surface roughness. In light of this, the present work seeks to provide a better understanding of the influence of milling parameters on cutting forces and surface finish when milling dies and molds. Milling tests were performed to investigate the effects of cutting strategy, lead angle and tool overhang (input variables) on cutting force components, and workpiece surface roughness (output variables). The results were evaluated by analysis of variance. The main conclusion was that surface roughness is directly related to radial force and that the cutting conditions that provided the lowest radial load (an upward strategy with a lead angle of 0°) produced the best surface roughness8412091218FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP2012/20816-2; 2013/00551-