Integration of CAD and rapid manufacturing for sand casting optimisation

International audienceIn order to reduce the time and costs of the products development in the sand casting process, the SMC Colombier Fontaine company has carried out a study based on tooling manufacturing with a new rapid prototyping process. This evolution allowed the adequacy of the geometry used for the simulation to the tooling employed physically in the production. This allowed a reduction of the wall thickness to 4?mm and retained reliable manufacturing process

A Comparison of Binder Burnout and Mechanical Characteristics of Printed and Chemically Bonded Sand Molds

Various material systems have been created for Binder Jetting of sand molds; however, a formal analysis comparing the materials to commonly used foundry molding materials has not been conducted. In this paper the authors investigate potential differences in the material properties from four different commercially available binders systems for chemically bonded sand molds. Specifically, the authors compared the binder burnout characteristics and the tensile strength of sand created by 3D printing and conventional chemically bonded molding materials. Increased binder content can strengthen the mold but have adverse effect on part quality. Understanding the binder characteristics of printed molds are essential due to the potential defects from large amounts of gas generated from binder while pouring molten metal.Mechanical Engineerin

A design-for-casting integrated approach based on rapid simulation and modulus criterion

This paper presents a new approach to the design of cast components and their associated tools. The current methodology is analysed through a case study and its main disadvantages underlined. Then, in order to overcome these identified drawbacks, a new approach is proposed. Knowing that this approach is mainly based on a rapid simulation of the process, basics of a simplified physical model of solidification are presented as well as an associated modulus criterion. Finally, technical matters for a software prototype regarding the implementation of this Rapid Simulation Approach (RSA) in a CAD environment are detailed

Tehnologije dodavanja materijala u metalurgiji – Studija slučaja produkcije ventila iz sivog lijeva

Additive Fabrication technologies are well known from the last two decades. In that time Additive Fabrication technologies have evolved from strictly prototype part production into an option that can also be used to produce end-user parts. With development of Additive Fabrication machines capable of producing metal parts, a complete substitution of conventional metal casting technologies is possible. However, direct Additive Fabrication of metal parts is still not time/cost effective when producing large volume parts, and nowadays there is still lack of materials that can be used on those machines. This paper presents a method how a conventional sand casting process can be assisted by Additive Fabrication technologies. A sand mould pattern is produced by Selective Laser Sintering. Additive Fabrication is also used in direct manufacturing of cores.Tehnologije sa dodavanjem materijala dobro su poznate od posljednja dva desetljeća. U to vrijeme tehnologije dodavanja su se razvije od tehnologija koje se upotrebljavaju strogo za brzo proizvodnju prototipnih dijelova, do tehnologija, sa kojima se može direktnu proizvodnju konačne produkte. Sa razvojem tehnologija za direktnu izradu metalnih dijelove, moguća je potpuna zamjena konvencionalnih tehnologija lijevanja metala. Međutim, direktna izrada dijelova još uvijek nije dovoljno ‘’cost efficient’’ kada su u pitanju komadi velikog volumna i danas još uvijek je samo nekoliko materijala , koji su testirani na strojevima za direktnu proizvodnju metalnih komada. Ovaj rad predstavlja metodu kako se mogu tehnologije dodavanja koristiti kao pomoć kod konvencionalnih lijevarskih procesa. Pješčani kalup izrađen je po postupku selektivnog laserskog sinteriranja pijeska, a postupci direktne proizvodnje su korišteni kod proizvodnje jezgra ventila

A design-for-casting integrated approach based on rapid simulation and modulus criterion

International audienceThis paper presents a new approach to the design of cast components and their associated tools. The current methodology is analysed through a case study and its main disadvantages underlined. Then, in order to overcome these identified drawbacks, a new approach is proposed. Knowing that this approach is mainly based on a rapid simulation of the process, basics of a simplified physical model of solidification are presented as well as an associated modulus criterion. Finally, technical matters for a software prototype regarding the implementation of this Rapid Simulation Approach (RSA) in a CAD environment are detailed

Emerging tools in casting technology and future of Aalto ENG foundry

Casting is the oldest metal manufacturing process known to humans. While the competence of casting technology has kept it popular since its advent, recent development in additive manufacturing has disrupted the status quo to some extent. Additive manufacturing is both acting as a competition through direct metal printing and also revolutionizing the casting technology through its inclusion at foundries in many different ways. This work starts with a literary study of comparison between casting and metal additive manufacturing. After wards, it discusses the emerging tools of casting technology which are becoming popular, many of which are possible through different additive manufacturing technologies. At the end, recommendations are given as to which of these tools could be implemented at Aalto Engineering foundry lab

Design for additive manufacturing: Trends, opportunities, considerations, and constraints

The past few decades have seen substantial growth in Additive Manufacturing (AM) technologies. However, this growth has mainly been process-driven. The evolution of engineering design to take advantage of the possibilities afforded by AM and to manage the constraints associated with the technology has lagged behind. This paper presents the major opportunities, constraints, and economic considerations for Design for Additive Manufacturing. It explores issues related to design and redesign for direct and indirect AM production. It also highlights key industrial applications, outlines future challenges, and identifies promising directions for research and the exploitation of AM's full potential in industry

Design for additive manufacturing: trends, opportunities, considerations, and constraints

© 2016 CIRP. The past few decades have seen substantial growth in Additive Manufacturing (AM) technologies. However, this growth has mainly been process-driven. The evolution of engineering design to take advantage of the possibilities afforded by AM and to manage the constraints associated with the technology has lagged behind. This paper presents the major opportunities, constraints, and economic considerations for Design for Additive Manufacturing. It explores issues related to design and redesign for direct and indirect AM production. It also highlights key industrial applications, outlines future challenges, and identifies promising directions for research and the exploitation of AM's full potential in industry

Desarrollo de un sistema de moldeo automatizado para piezas complejas en superaleaciones

El presente trabajo de investigación tiene como finalidad establecer las condiciones actuales del proceso de moldeo de la empresa de Cronite de México, así como el desarrollo de propuestas que ayuden a mejorar el mismo con la correcta implementación de tecnologías novedosas para el área de moldeo, estableciendo así un estándar de trabajo que no existe actualmente en México, incrementando la competitividad de la empresa en que la empresa es líder a nivel mundial. Para que esto se lleve a cabo deberán conocerse a fondo los procesos que se desarrollan en la empresa para así encontrar la tecnología que mejor se adapte a los procesos que la empresa realiza en la fabricación de sus productos. Actualmente la empresa cuenta con dos métodos de moldeo; el primero es el moldeo en verde, cuyo método ha sufrido muy pocos cambios desde su aparición en la antigüedad, y el método de moldeo con el uso de resinas, que, vale la pena señalarlo, es un método más “moderno” por haberse empezado a utilizar durante el siglo XX, sin embargo ambos métodos se basan en el mismo principio, la utilización de “modelos”. El moldeo de arena debe su éxito a que es un proceso muy simple, relativamente económico y ofrece una gran versatilidad que puede verse traducida en la fabricación de piezas de gran tamaño y con geometrías complejas. Justamente pensando en la versatilidad que ofrecen los métodos de moldeo de arena se ideó este proyecto de investigación, en el cual se tratará de llevar tecnología del siglo XXI al moldeo de arena, adecuando un sistema automatizado de fabricación de moldes, la idea es impactar en los tiempos de entrega de piezas, logrando producir prototipos en un menor tiempo, acortando así su validación y producción en masa. Para esto se deben tomar a consideración las propiedades con las que debe contar la arena que se desea utilizar, así como las herramientas que intervendrán en el proceso para hacer de este método algo posible