Introduction to Part Identification

Introduction to Part Identification

Why selecting the right applications matters.

Selecting the right components for Additive Manufacturing is important – no matter at which stage you are. Whether you are just getting started or want to increase the use of AM in your area, part selection never loses its importance.

In this course we will guide you in the process of selecting the right components for AM.

Reasons for part identification

Why selecting the right applications matters

Selecting the right components for Additive Manufacturing is important – no matter at which stage you are in. Whether you are just getting started or want to increase the use of AM in your area, part selection never loses its importance. Some of the reasons making part identification so important are:

  • Set realistic expectations on where AM has an influence on the company – and where not.
  • Understand which technologies and materials to focus on depending on your applications
  • Define your roadmap and strategy related to AM and identify key people that need to be trained. 

Bottom-up vs. top-down

How to find the right applications

Generally speaking, there are two different approaches to part identification: bottom-up and top-down. We propose a bottom-up approach, also referred to as personalized approach, towards identifying the right components for Additive Manufacturing. There are more and more automated tools coming up that promise an automatic identification of suitable parts using a top-down approach by screening your ERP and CAD data. While this might work for some specific cases, such as identifying polymer spare parts, this will in most cases not lead to the identification of parts that add the most value to your company.

We believe that it is you and your colleagues that know your parts best and need to be involved in the part identification process. The part screening process should thus include people from design, sales, purchasing, quality, management and other disciplines to ensure a holistic perspective. In this online learning we will present you a simple methodology and information that will guide you in the process.

Bottom-up

Bottom-up approach

Involvement of employees

Key employees are involved in the process early on

Identification based on experience

Different areas can be integrated into the part identification process

Easy data collection

Lower risk to make decisions based on outdated information

Time consuming training

Employees participating in part identification must be trained with AM skills

Possibly subjective

Evaluation and selection of parts depends on individuals

Screening limited to less parts

Bottom-up approach takes substantial time and is hard to scale

top-down

Top-down approach

Fast screening of many parts

Once the setup has been made, large amounts of parts can be screened automatically

Objective

Parts are objectively screened based on defined criteria

Difficult collection of relevant data

Hard to collect data from varying sources (SAP, CAD, technical drawings) in different formats (analog vs. digital)

Large amount of information

Huge amounts of data must be collected and verified

Software / search tool necessary

The top-down approach requires using software or search tool

Employees are not involved

A lack of involvement from employees can lead to resentment

The part identification process

Define your targets, screen suitable parts and realize your applications

The part identification process proposed in this online learning is structured into three distinct phases:

  • Definition of goals
  • Screening of suitable parts
  • Re-design and realiziation of identified components

In the following topic we will provide a quick overview of selected software tools that can support you in the part identification process.

We will then briefly cover the step Define your targets for the part identification process in the next module. The focus of this online learning will then be on step 2, the actual screening of parts.

Sinter-based AM technologies and process chain

Sinter-based AM - a technology overview

Many different printing technologies - one sintering process

The sinter-based AM (SBAM) technologies have, as the name suggests, the sintering process in common. In this process, the printed green part is consolidated into a dense part and receives its final properties. The green part can be printed in advance using different technologies.They all have in common that metal powder is bound to the desired shape by a binder. The best-known printing technologies include Binder Jetting and Filament Material Extrusion.

In this section, you learn everything about the sinter-based AM  process chain and get an overview of the different printing technologies.

Goal and structure of this course

This course is aimed at engineers, designers and other professionals that are working closely with sinter-based AM technologies. The goal is to cover the most important aspects that will enable engineers and designers to fully grasp the capabilities and technical limitations of the printing technologies and the sintering process to succeed in technology selection and part design. Besides going through the course from the beginning until the end, this course can also act as a constant source of knowledge while working on AM projects. 

The course is structured into the following sections.

This section will start with an overview of the sinter-based AM process chain and its printing technologies, followed by a technology deep dive into the most important aspects of the BJT technology, followed by a closer look at the debinding and sintering step also including sintering simulation .

The second section will provide an overview of the different materials that are available as well as part characteristics that can be achieved with the BJT process and typical methods for quality assurance. Finally, several common defects in the BJT process are presented. 

The last section will act as a guideline for designers. Besides generally describing the process when designing for Additive Manufacturing, actionable restrictions and guidelines for the BJT process are provided. The final section will present several design examples from different industries. 

What you will find in this section

Sinter-based AM process chain

From digital model to finished part

Data preparation

Simulation to compensate the deformation during the sintering step, nesting of parts and definition of printing parameters

Printing

Through various printing processes, different feedstocks such as metal powders, filaments, pellets or dispersions are processed into green parts

Unpacking

Unpacking of fragile green parts needs to be done carefully and is typically a manual process.

Debinding

Debinding describes the process of removing the binder which results in a brown part

Sintering

To reach the structural integrity of a metal part, a sinter process is required. The powder particles fuse together to a coherent, solid structure via a mass transport that occurs at the atomic scale driven via diffusional forces.

The brown part shrinks ~13-21 % in each direction.

The process chain of sinter-based technologies differs from other AM Technologies. Especially the post-printing processes (debinding and sintering) are crucial to achieve the intended mechanical properties.

Technology principle

How does Binder Jetting work?

Binder Jetting is a powder based Additive Manufacturing technology in which a liquid polymer binder is selectively deposited onto the powder bed binding the metal particles and forming a green body.

The metal powder is applied to a build platform in a typical layer thickness of 40 µm to 100 µm. Subsequently a modified 2D print head apply a binder selectively onto the powder bed. Depending on machine technology a hardening or curing process of the binder is performed in parallel for each layer and/or at the end of the whole build. During the in-situ curing process a heat source is used to solidify the binder and form a solid polymer – metal powder composite.

Working Principle of Binder Jetting

Afterwards the build platform moves downward by the amount of one layer thickness and a new layer of powder is applied. Again, the liquid binder is deposited and hardened in the required regions of the next layer to form the green body. This process is repeated until the complete part is printed. After the complete printing process is finished the parts have to be removed from the “powder cake” meaning the surrounding loose but densified powder. To improve the removal of the excess powder from the green body often brushes or a blasting gun with air pressure are used.

To create a dense metal part the 3D printed green body has to be post-processed in a debinding and sintering process. Similar to the metal injection molding process BJT parts are placed in a high temperature furnace, where the binder is burnt out and the remaining metal particles are sintered together. The sintering results in densification of the 3D printed green body to a metal part with high densities of 97 % to 99,5%, dependent of the material.

Printing Technologies

Metal Binder Jetting

Binder Jetting is a powder based Additive Manufacturing technology in which a liquid polymer binder is selectively deposited onto the powder bed binding the metal particles and forming a green body.

The metal powder is applied to a build platform in a typical layer thickness of 40 µm to 100 µm. Subsequently a modified 2D print head apply a binder selectively onto the powder bed. Depending on machine technology a hardening or curing process of the binder is performed in parallel for each layer and/or at the end of the whole build. During the in-situ curing process a heat source is used to solidify the binder and form a solid polymer – metal powder composite.

Working Principle of Binder Jetting

Material Extrusion

Binder Jetting is a powder based Additive Manufacturing technology in which a liquid polymer binder is selectively deposited onto the powder bed binding the metal particles and forming a green body.

The metal powder is applied to a build platform in a typical layer thickness of 40 µm to 100 µm. Subsequently a modified 2D print head apply a binder selectively onto the powder bed. Depending on machine technology a hardening or curing process of the binder is performed in parallel for each layer and/or at the end of the whole build. During the in-situ curing process a heat source is used to solidify the binder and form a solid polymer – metal powder composite.

Working Principle of Binder Jetting

Mold Slurry Deposition

Binder Jetting is a powder based Additive Manufacturing technology in which a liquid polymer binder is selectively deposited onto the powder bed binding the metal particles and forming a green body.

The metal powder is applied to a build platform in a typical layer thickness of 40 µm to 100 µm. Subsequently a modified 2D print head apply a binder selectively onto the powder bed. Depending on machine technology a hardening or curing process of the binder is performed in parallel for each layer and/or at the end of the whole build. During the in-situ curing process a heat source is used to solidify the binder and form a solid polymer – metal powder composite.

Working Principle of Binder Jetting

Metal Selective Laser Sintering

Binder Jetting is a powder based Additive Manufacturing technology in which a liquid polymer binder is selectively deposited onto the powder bed binding the metal particles and forming a green body.

The metal powder is applied to a build platform in a typical layer thickness of 40 µm to 100 µm. Subsequently a modified 2D print head apply a binder selectively onto the powder bed. Depending on machine technology a hardening or curing process of the binder is performed in parallel for each layer and/or at the end of the whole build. During the in-situ curing process a heat source is used to solidify the binder and form a solid polymer – metal powder composite.

Working Principle of Binder Jetting