Rapid manufacturing of metallic objects

Purpose - The purpose of this paper is to review additive and/or subtractive manufacturing methods for metallic objects and their gradual evolution from prototyping tools to rapid manufacture of actual parts. Design/methodology/approach - Various existing rapid manufacturing (RM) methods have been classified into six groups, namely, CNC machining laminated manufacturing, powder-bed technologies, deposition technologies, hybrid technologies and rapid casting technologies and discussed in detail. The RM methods have been further classified, based on criteria such as material, raw material form, energy source, etc. The process capabilities springing from these classifications are captured in the form of a table, which acts as a database. Findings - Due to the approximation in RM in exchange for total automation, a variety of multi-faceted and hybrid approaches has to be adopted. This study helps in choosing the appropriate RM process among these myriad technologies. Originality/value - This review facilitates identification of appropriate RM process for a given situation and sets the framework for design for RM.