prEN ISO/ASTM 52910
(Main)Additive manufacturing - Design - Requirements, guidelines and recommendations (ISO/ASTM DIS 52910:2022)
Additive manufacturing - Design - Requirements, guidelines and recommendations (ISO/ASTM DIS 52910:2022)
Additive Fertigung - Konstruktion - Anforderungen, Richtlinien und Empfehlungen (ISO/ASTMDIS52910:2022)
Fabrication additive - Conception - Exigences, lignes directrices et recommandations (ISO/ASTM DIS 52910:2022)
Dodajalna izdelava - Konstruiranje - Zahteve, smernice in priporočila (ISO/ASTM DIS 52910:2022)
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Standards Content (Sample)
SLOVENSKI STANDARD
01-september-2022
Aditivna proizvodnja - Načrtovanje - Zahteve, smernice in priporočila (ISO/ASTM
DIS 52910:2022)
Additive manufacturing - Design - Requirements, guidelines and recommendations
Additive Fertigung - Konstruktion - Anforderungen, Richtlinien und Empfehlungen
Fabrication additive - Conception - Exigences, lignes directrices et recommandations
Ta slovenski standard je istoveten z: prEN ISO/ASTM 52910
ICS:
25.030 3D-tiskanje Additive manufacturing
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
DRAFT INTERNATIONAL STANDARD
ISO/ASTM DIS 52910
ISO/TC 261 Secretariat: DIN
Voting begins on: Voting terminates on:
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Additive manufacturing — Design — Requirements,
guidelines and recommendations
Fabrication additive — Conception — Exigences, lignes directrices et recommandations
ICS: 25.030
This document is circulated as received from the committee secretariat.
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DRAFT INTERNATIONAL STANDARD
ISO/ASTM DIS 52910
ISO/TC 261 Secretariat: DIN
Voting begins on: Voting terminates on:
Additive manufacturing — Design — Requirements,
guidelines and recommendations
Fabrication additive — Conception — Exigences, lignes directrices et recommandations
ICS: 25.030
This document is circulated as received from the committee secretariat.
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ii
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PROVIDE SUPPORTING DOCUMENTATION. © ISO/ASTM International 2022
ISO/ASTM DIS 52910:2022(E)
Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Purpose . 1
5 Design opportunities and limitations . 5
5.1 General . 5
5.2 Design opportunities . 6
5.3 Design limitations . . 7
6 Design considerations . 8
6.1 General . 8
6.2 Product considerations . 8
6.3 Product usage considerations . 9
6.3.1 General . 9
6.3.2 Thermal environment . . 9
6.3.3 Chemical exposure . 9
6.3.4 Radiation exposure . 9
6.3.5 Other exposure . 10
6.4 Sustainability considerations . . 10
6.5 Business considerations . 11
6.6 Geometry considerations .13
6.7 Material property considerations . 15
6.7.1 General .15
6.7.2 Mechanical properties . .15
6.7.3 Thermal properties . 16
6.7.4 Electrical properties . 16
6.7.5 Other . 16
6.8 Process considerations . 17
6.8.1 General . 17
6.8.2 Specific process considerations . 17
6.8.3 Other considerations . 19
6.9 Communication considerations . 19
7 Warnings to designers .20
Bibliography .22
iii
© ISO/ASTM International 2022 – All rights reserved
ISO/ASTM DIS 52910:2022(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www.iso.org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation on the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to the
World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see the following
URL: www.iso.org/iso/foreword.html.
This document was prepared by ISO/TC 261, Additive manufacturing, in cooperation with ASTM F42,
Additive Manufacturing Technologies, on the basis of a partnership agreement between ISO and ASTM
International with the aim to create a common set of ISO/ASTM standards on additive manufacturing.
iv
© ISO/ASTM International 2022 – All rights reserved
DRAFT INTERNATIONAL STANDARD ISO/ASTM DIS 52910:2022(E)
Additive manufacturing — Design — Requirements,
guidelines and recommendations
1 Scope
This document gives requirements, guidelines and recommendations for using additive manufacturing
(AM) in product design.
It is applicable during the design of all types of products, devices, systems, components or parts that
are fabricated by any type of AM system. This document helps determine which design considerations
can be utilized in a design project or to take advantage of the capabilities of an AM process.
General guidance and identification of issues are supported, but specific design solutions and process-
specific or material-specific data are not supported.
The intended audience comprises three types of users:
— designers who are designing products to be fabricated in an AM system and their managers;
— students who are learning mechanical design and computer-aided design;
— developers of AM design guidelines and design guidance systems.
2 Normative references
There are no normative references in this document.
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO/ASTM 52900 apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
4 Purpose
4.1 This document provides requirements, guidelines and recommendations for designing parts
and products to be produced by AM processes. Conditions of the part or product that favour AM
are highlighted. Similarly, conditions that favour conventional manufacturing processes are also
highlighted. The main elements include the following:
— the opportunities and design freedoms that AM offers designers (Clause 5);
— the issues that designers should consider when designing parts for AM, which comprises the main
content of these guidelines (Clause 6);
— warnings to designers, or “red flag” issues, that indicate situations that often lead to problems in
many AM systems (Clause 7).
4.2 The overall strategy of design for AM is illustrated in Figure 1. It is a representative process for
designing mechanical parts for structural applications, where cost is the primary decision criterion.
© ISO/ASTM International 2022 – All rights reserved
ISO/ASTM DIS 52910:2022(E)
The designer could replace cost with quality, delivery time, or other decision criterion, if applicable. In
addition to technical considerations related to functional, mechanical or process characteristics, the
designer should also consider risks associated with the selection of AM processes.
4.3 The process for identifying general potential for fabrication by AM is illustrated in Figure 2. This is
an expansion of the “identification of general AM potential” box on the left side of Figure 1. As illustrated,
the main decision criteria focus on material availability, whether or not the part fits within a machine’s
build volume, and the identification of at least one part characteristic (customization, lightweighting,
complex geometry) for which AM is particularly well suited. These criteria are representative of many
mechanical engineering applications for technical parts, but are not meant to be complete.
4.4 An expansion for the “AM process selection” box in Figure 1 is presented in Figure 3, illustrating
that the choice of material is critical in identifying a suitable process or processes. If a suitable
material and process combination can be identified, then consideration of other design requirements
can proceed, including surface considerations and geometry, static physical and dynamic physical
properties, among others. These figures are meant to be illustrative of typical practice for many types
of mechanical parts, but should not be interpreted as prescribing necessary practice.
© ISO/ASTM International 2022 – All rights reserved
ISO/ASTM DIS 52910:2022(E)
Figure 1 — Overall strategy for design for AM
© ISO/ASTM International 2022 – All rights reserved
ISO/ASTM DIS 52910:2022(E)
Figure 2 — Procedure for identification of AM potential
© ISO/ASTM International 2022 – All rights reserved
ISO/ASTM DIS 52910:2022(E)
Material: metal
Powder bed Material
Main technical issues Material jetting Sheet lamination
fusion extrusion
Surface
Roughness
Staircase effect
Geometrical properties
Geometrical accuracy
Static physical properties
Porosity
Tensile strength
Ductility
Dynamic physical properties
Life cycle fatigue
Figure 3 — Parameters for the AM process selection
5 Design opportunities and limitations
5.1 General
Additive manufacturing differs from other manufacturing processes for several reasons and these
differences lead to unique design opportunities and freedoms that are highlighted here. As a general
rule, if a part can be fabricated economically using a conventional manufacturing process, that part
should probably not be produced using AM. Instead, parts that are good candidates for AM tend to have
complex geometries, custom geometries, low production volumes, special combinations of properties
or characteristics, or some combination of these characteristics. As processes and materials improve,
the emphasis on these characteristics will likely change. In Clause 5, some design opportunities are
highlighted and some typical limitations are identified.
© ISO/ASTM International 2022 – All rights reserved
ISO/ASTM DIS 52910:2022(E)
5.2 Design opportunities
5.2.1 Background — AM fabricates parts by adding material in a layer-by-layer manner. Due to the
nature of AM processes, AM has many more degrees of freedom than other manufacturing processes.
For example, a part can be composed of millions of droplets if fabricated in a material jetting
process. Discrete control over millions of operations at micro to nano scales is both an opportunity
and a challenge. Unprecedented levels of interdependence are evident among considerations and
manufacturing process variables, which distinguishes AM from conventional manufacturing processes.
Capabilities to take advantage of design opportunities can be limited by the complexities of process
planning.
5.2.2 Overview — The layer-based, additive nature means that virtually any part shapes can be
fabricated without hard tooling, such as moulds, dies or fixtures. Geometries that are customized to
individuals (customers or patients) can be economically fabricated. Very sophisticated geometric
constructions are possible using cellular structures (honeycombs, lattices, foams) or more general
structures. Often, multiple parts that were conventionally manufactured can be replaced with a single
part, or smaller number of parts, that is geometrically more complex than the parts being replaced.
This can lead to the development of parts that are lighter and perform better than the assemblies they
replace. Furthermore, such part count reduction (called part consolidation) has numerous benefits for
downstream activities. Assembly time, repair time, shop floor complexity, replacement part inventory
and tooling can be reduced, leading to cost savings throughout the life of the product. An additional
consideration is that geometrically complex medical models can be fabricated easily from medical
image data.
5.2.3 In many AM processes, material compositions or properties can be varied throughout a part.
This capability leads to functionally graded parts, in which desired mechanical property distributions
can be fabricated by varying either material composition or material microstructure. If effective
mechanical properties are desired to vary throughout a part, the designer can achieve this by taking
advantage of the geometric complexity capability of AM processes. If varying material composition or
microstructure is desired, then such variations can often be achieved, but with limits dependent on the
specific process and machine. Across the range of AM processes, some processes enable point-by-point
material variation control, some provide discrete control within a layer, and almost all processes enable
discrete control between layers (vat photopolymerization is the exception). In the material jetting and
binder jetting processes, material composition can be varied in virtually a continuous manner, droplet-
to-droplet or even by mixing droplets. Similarly, the directed energy deposition process can produce
variable material compositions by varying the powder composition that is injected into the melt pool.
Discrete control of material composition can be achieved in material extrusion processes by using
multiple deposition heads, as one example. Powder bed fusion (PBF) processes can have limitations
since difficulties can arise in separating unmelted mixed powders. It is important to note that specific
machine capabilities will change and evolve over time, but the trend is toward increasing material
composition flexibility and property control capability.
5.2.4 A significant opportunity exists to optimize the design of parts to yield unprecedented
structural properties. The concept of “design for functionality” can be realized, meaning that if a part’s
functions can be defined mathematically, the part can be optimized to achieve those functions. Novel
topology and shape optimization methods have been developed in this regard. Resulting designs can
have very complex geometric constructions, utilizing honeycomb, lattice or foam internal structures,
can have complex material compositions and variations, or can have a combination of both. Research is
needed in this area, but some examples of this are emerging.
5.2.5 Other opportunities involve some business considerations. Since no tooling is required for part
fabrication using AM, lead times can be very short. Little investment in part-specific infrastructure is
needed, which enables mass customization and responsiveness to market changes. In the case of repair,
remanufacturing of components could be highly advantageous both from cost as well as lead time
perspectives.
© ISO/ASTM International 2022 – All rights reserved
ISO/ASTM DIS 52910:2022(E)
5.3 Design limitations
5.3.1 Overview — It is useful to point out design characteristics that indicate situations when
AM should probably not be used. Stated concisely, if a part can be fabricated economically using
a conventional manufacturing process and can meet requirements, then it is not likely to be a good
candidate for AM. The designer should balance cost, value delivered and risks when deciding whether
to pursue AM.
5.3.2 A primary advantage of AM processes is their flexibility in fabricating a variety of part shapes,
complex and customized shapes, and possibly complex material distributions. If one desires mass
production of simple part shapes in large production volumes, then AM is not likely to be suitable
without significant improvements in fabrication time and cost.
5.3.3 A designer shall be aware of the material choices available, the variety and quality of feedstocks,
and how the material’s mechanical and other physical properties vary from those used in other
manufacturing processes. Materials in AM have different characteristics and properties because they
are processed differently than in conventional manufacturing processes. Designers should be aware
that the properties of AM components are highly sensitive to process parameters and that process
variability is a significant issue that can constrain freedom of design. Additionally, designers should
understand the anisotropies that are often present in AM processed materials. In some processes,
properties in the build plane (X, Y directions) are different than in the build direction (Z axis). With
some metals, mechanical properties better than wrought can be achieved. However, typically fatigue
and impact strength properties are not as good in AM processed parts in their as-built state as in
conventionally processed materials.
5.3.4 All AM machines discretize part geometry prior to fabricating a part. The discretization can
take several forms. For example, most AM machines fabricate parts in a layer-by-layer manner. In
material and binder jetting, discrete droplets of material are deposited. In other processes, discrete
vector strokes (e.g. of a laser) are used to process material. Due to the discretization of part geometry,
external part surfaces are often not smooth since the divisions between layers are evident. In other
cases, parts can have small internal voids.
5.3.5 Geometry discretization has several other effects. Small features can be ill-formed. Thin walls
or struts that are slanted, relative to the build direction, can be thicker than desired. Also, if the wall
or strut is nearly horizontal, the wall or strut can be very weak since relatively little overlap can occur
between successive layers. Similarly, small negative features such as holes can suffer the opposite
effect, becoming smaller than desired and having distorted shapes.
5.3.6 Post-processing is required for many AM processes or can be desired by the end user. A variety
of mechanical, chemical and thermal methods may be applied. Several AM process types utilize support
structures when building parts which need to be removed. In some cases, supports can be removed
using solvents, but in others the supports have to be mechanically removed. One should be aware of
the additional labour, manual component handling and time these operations require. Additionally,
designers should understand that the presence of support structures can affect the surface finish or
accuracy of the supported surfaces. In addition to support structure removal, other post-processing
operations can be needed or desired, including excess powder removal, surface finish improvement,
machining, thermal treatments and coatings. If a part has any internal cavities, the designer should
design features into the part that enable support structures, unsintered powder (PBF) or liquid resin
(VP) to be removed from those cavities. Depending on accuracy and surface finish requirements, the
part can require finish machining, polishing, grinding, bead blasting or shot-peening. Metal parts can
require a thermal treatment for relieving residual stresses, for example. Coatings can be required, such
as painting, electroplating or resin infiltration. Post processing operations increase the cost of AM
components.
© ISO/ASTM International 2022 – All rights reserved
ISO/ASTM DIS 52910:2022(E)
5.3.7 Each AM process has a limited build envelope. If a part is larger than the build envelope of an
AM process, then it can be divided into multiple parts, which are to be assembled after fabrication. In
some cases, this is not technically or economically feasible.
6 Design considerations
6.1 General
Several categories of design considerations have been identified, including product, usage, sustainability,
business, geometric, material property, process and communication considerations.
6.2 Product considerations
6.2.1 Design effectiveness — The designer can generate part shapes and configurations that optimize
performance and efficiency. Parts can be designed for desired properties, such as minimum weight,
maximum stiffness, etc., by designing shapes that are as efficient as possible. It can also be possible to
design a part to perform multiple functions, through the use of multiple materials, complex shapes or
part consolidation, which can have significant efficiency benefits.
6.2.2 Part or product consolidation — It is good design practice to minimize the number of parts in a
product or module, but not at a loss of functionality. A part can be merged into neighbouring part(s) if
they can be fabricated out of the same material, do not need to move relative to each other, and do not
need to be removed to enable access to another part. This practice is often called part consolidation,
which is a standard design-for-assembly consideration.
6.2.3 Assembly features — This is a standard design-for-assembly consideration. One should design
parts with features that enable easy insertion and fixation during assembly operations. AM can
enable integration of assembly features into most part designs, such as snap-fits, alignment features
and features to support other parts (ribs, bosses). The capability of AM to fabricate geometrically
complex designs provides a greater degree of design flexibility/freedom and designers are encouraged
to be innovative in designing assembly features. Designers should also take note of the assembly
requirements where mating surfaces require additional traditional machining, for AM metal parts
in particular. For example, there are design considerations where a part is designed for conventional
machining followed by assembly.
6.2.4 Multi-part mechanisms — In many AM processes, it is possible to design working mechanisms,
i.e. parts that move relative to one another, without the need for secondary assembly operations.
Kinematic joints, such as revolute, sliding and cam joints, can be designed to enable relative motion
between parts. In powder bed fusion processes, joints can provide motion if powder can be removed.
In vat photopolymerization processes, liquid resin easily flows out of joints, which enables motion. In
other processes requiring support structures, moving mechanisms are possible if the support material
can be removed easily from joint regions, for example if soluble support material is used.
6.2.5 Compliant mechanisms — AM can enable creative designs of complex 2D and 3D mechanisms. In
contrast to multi-part mechanisms, other types of mechanisms cause relative movement between the
input and the output through designed bending patterns. That is, structural elements of the mechanism
bend in a manner that causes desired input-output behaviour. The simplest types of compliant
mechanisms simply replace pin joints with thin plates that act as compliant hinges.
6.2.6 Relationships with processes and process chains — The accuracy and surface finish of part
surfaces depend on build orientation and other process variables. A sequence of processes (“process
chain”) can be needed in order to achieve desired accuracy and finish requirements, which the designer
needs to consider. By designing a suitable process chain, it can be possible to use an AM process for part
fabrication, even if that process alone is not capable of meeting all design requirements.
© ISO/ASTM International 2022 – All rights reserved
ISO/ASTM DIS 52910:2022(E)
6.3 Product usage considerations
6.3.1 General
Design considerations shall also be based upon the type of environment which the product experiences
throughout its useful life. This can include operating conditions, but can also refer to conditions
in storage or during maintenance and repair. Material properties can be affected by the following
environmental conditions.
6.3.2 Thermal environment
6.3.2.1 Exposure temperature range (extremes) — The maximum and minimum temperatures to
which the product is exposed should be defined. The designer should ensure that the selected part
material maintains the required physical properties over the entire temperature range that the
product experiences during its operational life. Product designs need to be functional over the entire
temperature range.
6.3.2.2 Operational temperature range — The material properties should exceed the required
functional performance when exposed to the entire temperature range the product will experience
over the majority of its operational life. The designer should ensure that the selected part material
maintains required physical geometry and material properties over its operational temperature range.
6.3.2.3 Cyclic thermal exposure (or thermal fatigue) — Periodic thermal changes that the product
experiences during its operational life can permanently degrade material properties (i.e. aging).
6.3.2.4 Coefficient of thermal expansion (CTE) properties — Thermal expansion of the product while
operating near or at the extremes of its temperature range can change part geometry and material
properties. CTE mismatch between mating components can lead to induced stresses and potentially
failures. This is commonly reported using ASTM E228.
6.3.3 Chemical exposure
6.3.3.1 Chemicals — Identification of chemicals that can come in contact with the product should be
determined due to possible chemical reactivity with the product material.
6.3.3.2 Liquid absorption — Some AM materials can absorb certain liquids that contact them, possibly
causing the material to swell, degrade or suffer other unintended negative consequences.
6.3.3.3 Degradation/aging of material — This is a possible consequence of exposure to chemicals,
whether they are gases, liquids or solids. This can also be a consequence of usage, wear-and-tear, etc. An
example is humidity; a product might not have a problem in dry (arid) areas but fail when it is operating
in a more humid environment.
6.3.3.4 Forms of corrosion — The surrounding materials and the environment in which the AM
metallic product will be in contact need to be understood to mitigate all possible forms of corrosion.
6.3.4 Radiation exposure
6.3.4.1 Non-ionizing — Damaging radiation such as visible light, radio waves, microwaves and low
level exposures to UV light can affect material properties depending upon exposure levels.
6.3.4.2 Ionizing — Alpha, beta, cosmic rays, gamma rays and X-ray radiation exposure levels need to
be considered for possible effects to material properties.
© ISO/ASTM International 2022 – All rights reserved
ISO/ASTM DIS 52910:2022(E)
6.3.5 Other exposure
6.3.5.1 Biological exposure — Exposure to biological materials can cause material degradation or
changes in properties. These materials can include human fluids or tissues, other animal fluids or
tissues, plants or plant tissues, and algae or other microscopic organisms. Many of these considerations
are covered by US FDA or other international regulations and designers should reference the relevant
regulations.
6.3.5.2 Environmental combinations — Combinations of all environmental considerations (thermal,
chemical and radiation) need to be considered as material properties are affected when multiple
conditions are present.
6.4 Sustainability considerations
6.4.1 Companies, consumers and governments often want to understand the impact of a product and
its manufacturing process on the Earth’s environment and natural resources. Sustainability typically
deals with ecological impact and the desire to reduce negative human impact. As such, the topic of
sustainability deserves attention when designing parts to be fabricated by AM. The presentation of
considerations starts with the concept of reduce, recycle and reuse.
6.4.2 Reduce — Reduction in material content in parts can yield significant savings over the lifetime
of a product. For example, a 1 kg reduction in airplane mass across a fleet can save many thousands of
litres of jet fuel and eliminate millions of kilograms of CO emissions per year. Compared to conventional
manufacturing processes, no tooling is needed, which reduces the usage of material during fabrication.
Another example is the elimination of initial “stock” for machining and the need to machine off the
majority of the material in order to fabricate a complex part. Designers are encouraged to use available
design freedom to creatively design parts to be as efficient as possible while achieving all requirements.
6.4.3 Recycle — Recyclability refers to the capability of recovering the materials used in a part or
product. Recycled materials become raw materials for a subsequent manufacturing process. Typically,
metals are easily recycled, many thermoplastics are recyclable (to an extent), but thermoset polymers
are not typically recyclable. ABS, polycarbonate (used in extrusion processes) and polyamide (used
in polymer powder bed fusion) tend to be recyclable; however, designers should check the particular
polymer blends used for AM processes. Typically the photopolymers used in material jetting and vat
photopolymerization processes are not recyclable.
Although most materials are, technically, recyclable, limitations exist in many instances where specific
materials are not commercially recycled due to various factors, including logistics, separation issues
or economics. Users are advised to take this into consideration when evaluating this aspect of material
selection.
6.4.4 Recycling logos — Originally developed by the Society of Plastics Industry (SPI), the resin
identification coding system dictates the symbols to be used on plastic parts to indicate the specific
polymer composition of the part. The ASTM committee D20 currently manages the resin identification
coding system and has developed a standard practice for this topic as ASTM D7611-13. The identification
symbols are readily visible on consumer parts and are often used in community recycling programs to
assist workers in separating different materials. Part designers should add these resin identification
code symbols to their designs if parts are to be used for production purposes.
6.4.5 Reuse — Reuse refers to using a part after its original use without destroying its geometry,
as is done in material recycling. Often, a reused part is used for a different purpose, one that is not as
demanding on the part’s properties. Other times, a part can be refurbished and reused for its original
purpose. If a company wants to pursue a reuse strategy, then designers should design parts for extended
lifetimes. Hence, there can be a tradeoff between “reduce” objectives and “reuse” objectives.
© ISO/ASTM International 2022 – All rights reserved
ISO/ASTM DIS 52910:2022(E)
6.4.6 Input stream — This generally refers to the materials that are inputs to the various
manufacturing processes, including the materials from which parts will be fabricated, support
structure materials, etc. In many powder bed fusion processes, powder is reused from one build to
the next. This powder recycling is important from an economic viewpoint, but has limits. Typically
AM process feedstock is very carefully controlled by the AM machine vendors to ensure quality parts,
reducing the importance of input stream considerations. However, as a wider variety of feedstocks is
accepted, part designers will need to consider material choices carefully so that they have confidence
that claimed physical properties are representative of as-fabricated properties.
6.4.7 Waste stream — The materials that remain after a product is dismantled and recyclable
materials are separated are typically considered waste; these materials become the waste stream.
In the case of AM processes, the products of part post-processing shall also be considered wastes,
including support structures (except metal supports), cleaning solvents and powders that can no longer
be recycled in powder bed fusion machines.
6.4.8 Energy consumption — Considerable energy can be consumed during part fabrication. AM
machines use energy while heating up, processing materials, and even during cool-down if fans are
running. This is not something that is easy to evaluate when designing parts or selecting manufacturing
processes, but should become of increasing interest to AM machine vendors. Designers should also
include energy consumption during post processing and finishing of parts.
6.4.9 Water consumption — Many companies are very concerned about water usage in factories, since
in many parts of the world, water is a scarce resource. Some vat photopolymerization processes require
considerable amounts of water for post-processing.
6.4.10 Carbon footprint — This is a more general type of sustainability analysis that deals with most
aspects of part manufacture across the supply chain. Carbon footprint is an overall measure of resources
consumed and pollution emitted that starts with the extraction and processing of raw materials (e.g.
mining) and ends with the recycling of product materials or reuse of parts. Good databases and tools
are available for evaluating the carbon footprint of parts manufacturing for many common materials
and many common manufacturing processes.
6.4.11 Life-cycle impact — Some summary comments can be made. It is important to consider that
AM processes can be replacing other manufacturing processes and evaluations of the impact of AM
production should be determined relative to the impacts of these other processes. Just because an AM
process can consume significant energy, for example, does not mean it should not be used. The total
impact (energy, water, carbon footprint, wastes, etc.) should be considered of the entire alternative
process chains for the expected product life. Furthermore, the overall life-cycle impact of the product,
given material and process choices, should be determined before adopting or rejecting the use of AM.
6.5 Business considerations
6.5.1 There are several business considerations when deciding if AM is the best method for production
of a part.
6.5.2 Cost — There are several aspects to the consideration of cost: AM fabrication cost, total part
fabrication cost, life cycle cost and up front engineering cost, among others.
6.5.2.1 AM fabrication cost — Is it more effective to use AM? This consideration requires a cost
analysis capability for the target process. Furthermore, it will be helpful if cost analyses are available
for several AM processes and for one or more conventional manufacturing processes so that relative
comparisons can be made. The capability of considering multiple materials will also be useful.
6.5.2.2 Total part fabrication cost — A process chain can be necessary to fabricate a part, where AM is
only one process in the chain. Costs for all of these processes should be considered.
© ISO/ASTM International 2022 – All rights reserved
ISO/ASTM DIS 52910:2022(E)
6.5.2.3 Up front engineering costs — Extensive design freedom can be a significant benefit, but
considerable time and cost can be expended in searching extensive design spaces. Additionally,
considerable time can be spe
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