Abstract
There are many 3D printing technologies available, and each technology has its strength and weakness. The 3D printing of sand moulds, by binder jetting technology for rapid casting, plays a vital role in providing a better value for the more than 5000 years old casting industry by producing quality and economic sand moulds. The parts of the mould assembly can be manufactured by precisely controlling the process parameters and the gas-producible materials within the printed mould.
A functional mould can be manufactured with the required gas permeability, strength, and heat absorption characteristics, and hence the process ensures a high success rate of quality castings with an optimised design for weight reduction. It overcomes many of the limitations in traditional mould design with a very limited number
of parts in the mould assembly. A variety of powders, of different particle sizes or shapes, and bonding materials can be used to change the thermal and physical properties of the mould and hence provide possibilities for casting a broad range of alloys.
Limited studies have been carried out to understand the relationship between the characteristics of the printed mould, the materials used, and the processing parameters for making the mould. These deficiencies need to be addressed to support the numerical simulation of a designed part, to optimise the success rate and for economic as well as environmental reasons. Commonly used binders in this process, e.g. furan resins, are carcinogenic or hazardous, and hence there is a vital need for developing new or improved bonding materials.
1. Introduction
A definition of additive manufacturing (AM) has been given as the “process of joining materials to make parts from 3D model data, usually
layer upon layer, as opposed to subtractive manufacturing and formative manufacturing methodologies”. AM began as a method for
design engineers to realise design concepts without heavily investing in the subsequent manufacturing processes. Advancements in Rapid Prototyping (RP) enabled the conversion of parametric CAD (computer-aided design) data to physical prototypes which could be tested to check if they met the design criteria. This saved not only time but also allowed the testing of multiple models.
Since then, its applications have expanded into the aerospace industry, medicine, architecture and more. This expansion has been aided by
the wide-scale development and innovation in additive manufacturing processes. As the accuracy and the versatility of the processes
improve, the focus of the industry is shifting from Rapid Prototyping to ‘Rapid Manufacturing’ i.e. the process of manufacturing
complete parts from a rapid prototyping device.
For further details, please visit the link:
https://pfa.org.pk/wpcontent/uploads/2017/04/3D_printing_for_rapid_sand_casting_A_rev.pdf
