ISO/TC 261/JWG 11 - Joint ISO/TC 261 - ISO/TC 61/SC 9 WG: Additive manufacturing for plastics

This document establishes the required or the achievable classes of part properties for additive manufactured polymer parts in order to get a common understanding on part quality. It is aimed at providers of manufacturing services for polymer parts who use additive manufacturing machines and at the customers for these services. Designers of parts as well as buyers and providers of manufacturing services can specify, in a traceable manner, the required or the achievable level of part properties with the aid of this document. The classification is based on mechanical, physical and geometrical properties. Further properties can be defined between buyer and provider of manufacturing. This document is applicable to parts that have been manufactured from a thermoplastic polymer by means of thermal reaction fusion of material typically applied by a powder bed fusion (PBF) or material extrusion (MEX) processes. This document is also applicable to thermoplastic parts made by other processes, provided that due consideration is given to process-specific topics. The classification of part properties applies to parts in as-built condition, that have been unpacked from the build space, with all support structures removed, but prior to any post-processing operations. Specific industries (e.g. aerospace and medical) typically specify additional requirements.

This document specifies the general principles to be followed when test specimens of thermoplastic materials are prepared by laser-based powder bed fusion (PBF-LB/P), which is commonly known as laser sintering. The (PBF-LB/P) process is used to prepare test specimens layer upon layer in which thermal energy selectively fuses regions of a powder bed. This document provides a basis for establishing reproducible and reportable sintering conditions. Its purpose is to promote uniformity in describing the main process parameters, build orientation of the sintering process and also to establish uniform practice in reporting sintering conditions. This document does not specify the test procedure itself.

This document provides guidance and recommendations for the qualification of polymeric materials intended for laser-based powder bed fusion of polymers (PBF-LB/P). The parameters and recommendations presented in this document relate mainly to the material polyamide 12 (PA12), but references are also made to polyamide 11 (PA11). The parameters and recommendations set forth herein cannot be applicable to other polymeric materials.

ISO 27547-1:2010 specifies the general principles of test specimen preparation using mouldless techniques. Sometimes, these techniques are called “tool-less” methods. Common to all these techniques is the fact that the specimens are produced layer by layer. The shape and dimensions of the specimens are defined in terms of a numerical description using CAD techniques. This computer model of the specimen is “sliced” into layers by means of suitable software. The specimen-preparation process then builds up the specimens automatically, layer by layer, using the computer model and a suitable computer-controlled laser-sintering machine. The three software systems used (for CAD, slicing the specimen into layers and machine control) may be independent systems interfacing separately with the machine or they may be integrated with the machine. This part of ISO 27547 also specifies the general principles to be followed when test specimens of thermoplastic materials are prepared by laser sintering. The laser-sintering process is used to prepare specimens layer-wise by sintering the particles of a thermoplastic powder using the energy of a laser beam. This part of ISO 27547 provides a basis for establishing reproducible sintering conditions. Its purpose is to promote uniformity in describing the main parameters of the sintering process and also to establish uniform practice in reporting sintering conditions.