Next Generation Materials Testing: Obtaining Anisotropic Plasticity Parameters using Profilometry-based Indentation Plastometry (PIP)
Lead Research Organisation:
Plastometrex
Department Name: Research and development
Abstract
Mechanical testing is routinely used in almost all industrial sectors. It is used to ensure the quality and safety of components (often mandated by regulations), to reveal important relationships between processing and properties, and to support the development of new materials and novel material systems.
The gold-standard for mechanical testing is the tensile test, which measures the stress-strain properties of materials. This test involves machining of a large test coupon and requires access to a universal mechanical test machine. Although widely used, the tensile test can be time-consuming and cumbersome, with testing turnaround times of hours or even several days if outsourced, and the machinery and capital set-up costs are high. In addition, the tests result in the destruction of the sample and they generate large amounts of wasted material. Despite the clear need for improved testing methods, a risk averse sector and an over-reliance on compliance with the testing standards has hampered progress within this area. It is now evident that current testing procedures are out-dated and inflexible. There is a strong motivation for developing faster, more efficient, more cost-effective, and less wasteful testing methods.
The Plastometrex (PLX) team have developed an innovative mechanical testing method for metallic materials called PIP (or Profilometry-based Indentation Plastometry). PIP measures the same stress-strain properties as the tensile test while overcoming many of its limitations. It is simple to use, reduces testing turnaround times from hours to just three minutes, sample preparation requirements are minimal, and real components can be tested. It is similar in execution to the common hardness test, but unlike the hardness test the entire residual profile shape is measured. The PIP methodology involves three main tasks: (1) Creation of an indent using our Indentation Plastometer (see www.plastometrex.com), (2) Measurement of the residual profile shape using an integrated stylus profilometer, and (3) Analysis of the residual profile shape using our proprietary software package - SEMPID.
PIP is well-suited for materials that are isotropic, i.e. its properties are the same in all directions. However some materials, such as additively manufactured (AM) metals, are anisotropic, i.e. their properties vary depending on the orientation. This research project will extend the capabilities of PIP to include anisotropic materials with a focus on AM metals, allowing quantitative assessment of the properties in different directions. AM could revolutionise the high value manufacturing sector, allowing rapid prototyping, radical design innovation, lower tooling costs, reduced time to market and lower production costs, waste and emissions. This research will allow these components to be rapidly tested, and provide manufacturers with almost real-time feedback on the properties of their parts. Therefore, it is an enabler for AM technology and the potential benefits for manufacturing and wider society that this brings.
The research will mainly take place at Plastometrex Ltd, the host organisation of the fellow, based at the Cambridge Science Park. The research will involve a significant amount of laboratory experiments and modelling work. Oxford University are partners on the project, with their interest in high-throughput testing of AM superalloys, a family of materials that are ubiquitous in aero-engine and power-generation industries. The Manufacturing Technology Centre (MTC) are collaborators on the project. They will provide materials for the research, equipment for characterising the amount of structure of porosity, and their leading knowledge of materials, processing and post-processing for AM metals. The National Physical Laboratory (NPL) will collaborate on the development of a standard for the methodology and conduct tensile test experiments for blind testing as part of technology validation.
The gold-standard for mechanical testing is the tensile test, which measures the stress-strain properties of materials. This test involves machining of a large test coupon and requires access to a universal mechanical test machine. Although widely used, the tensile test can be time-consuming and cumbersome, with testing turnaround times of hours or even several days if outsourced, and the machinery and capital set-up costs are high. In addition, the tests result in the destruction of the sample and they generate large amounts of wasted material. Despite the clear need for improved testing methods, a risk averse sector and an over-reliance on compliance with the testing standards has hampered progress within this area. It is now evident that current testing procedures are out-dated and inflexible. There is a strong motivation for developing faster, more efficient, more cost-effective, and less wasteful testing methods.
The Plastometrex (PLX) team have developed an innovative mechanical testing method for metallic materials called PIP (or Profilometry-based Indentation Plastometry). PIP measures the same stress-strain properties as the tensile test while overcoming many of its limitations. It is simple to use, reduces testing turnaround times from hours to just three minutes, sample preparation requirements are minimal, and real components can be tested. It is similar in execution to the common hardness test, but unlike the hardness test the entire residual profile shape is measured. The PIP methodology involves three main tasks: (1) Creation of an indent using our Indentation Plastometer (see www.plastometrex.com), (2) Measurement of the residual profile shape using an integrated stylus profilometer, and (3) Analysis of the residual profile shape using our proprietary software package - SEMPID.
PIP is well-suited for materials that are isotropic, i.e. its properties are the same in all directions. However some materials, such as additively manufactured (AM) metals, are anisotropic, i.e. their properties vary depending on the orientation. This research project will extend the capabilities of PIP to include anisotropic materials with a focus on AM metals, allowing quantitative assessment of the properties in different directions. AM could revolutionise the high value manufacturing sector, allowing rapid prototyping, radical design innovation, lower tooling costs, reduced time to market and lower production costs, waste and emissions. This research will allow these components to be rapidly tested, and provide manufacturers with almost real-time feedback on the properties of their parts. Therefore, it is an enabler for AM technology and the potential benefits for manufacturing and wider society that this brings.
The research will mainly take place at Plastometrex Ltd, the host organisation of the fellow, based at the Cambridge Science Park. The research will involve a significant amount of laboratory experiments and modelling work. Oxford University are partners on the project, with their interest in high-throughput testing of AM superalloys, a family of materials that are ubiquitous in aero-engine and power-generation industries. The Manufacturing Technology Centre (MTC) are collaborators on the project. They will provide materials for the research, equipment for characterising the amount of structure of porosity, and their leading knowledge of materials, processing and post-processing for AM metals. The National Physical Laboratory (NPL) will collaborate on the development of a standard for the methodology and conduct tensile test experiments for blind testing as part of technology validation.
Publications
Southern T
(2023)
Indentation Plastometry for Study of Anisotropy and Inhomogeneity in Maraging Steel Produced by Laser Powder Bed Fusion
in steel research international
Reiff-Musgrove R
(2023)
Indentation Plastometry of Particulate Metal Matrix Composites, Highlighting Effects of Microstructural Scale
in Advanced Engineering Materials
Reiff-Musgrove R
(2022)
Effect of Relatively Low Levels of Porosity on the Plasticity of Metals and Implications for Profilometry-Based Indentation Plastometry
in Advanced Engineering Materials
Description | Metals that can be produced by 3D printing can show different mechanical properties in different regions. These variations are difficult or impossible to measuring using conventional methods for testing these materials. It has been demonstrated within this award that some materials show very marked differences in properties (> 10 %) in different locations and these can be accurately measured using indentation, but not readily measured using the conventional methods for testing these materials. |
Exploitation Route | These outcomes can be used throughout the 3D printing of metals industry, which is growing rapidly, to understand the mechanical properties of the materials being produced more completely. To ensure that this method can be used as widely as possible, an international standard is being drafted with support from researchers at the Korea Institute of Materials Science, to allow widespread adoption in the industry. |
Sectors | Aerospace Defence and Marine Digital/Communication/Information Technologies (including Software) Education Energy Manufacturing including Industrial Biotechology |
URL | https://doi.org/10.1002/srin.202200881 |
Description | Entry 1: Findings from the first 9 months have already supported improvements to software products which are used by current Plastometrex customers. These improvements are likely to lead to increased usage of the products, and therefore economic benefits the the company and UK economy. Significant IP has been generated. Currently held as internal 'know how' but it is likely that this will translate into a patent in due course. Case studies with collaborators have been used to drive awareness of the project, driving more interactions with other companies/academics/institutions and wider research ideas. Entry 2: In the second year of the project, significant IP has been generated for which a patent will soon be applied and therefore limited information is given. A draft international standard has been produced, using findings directly from this project. Further refinements to products have been made on the basis of research findings from this project and new collaborations with influential companies in the space have promoted further interest. |
First Year Of Impact | 2023 |
Sector | Aerospace, Defence and Marine,Construction,Energy,Government, Democracy and Justice,Manufacturing, including Industrial Biotechology,Transport |
Impact Types | Societal Economic |
Description | Plastometrex and Alloyed Ltd. |
Organisation | Alloyed |
Department | Materials design and new product development |
Country | United Kingdom |
Sector | Private |
PI Contribution | Access to machines, machining of samples, analysis of data and preparation of materials for external dissemination. |
Collaborator Contribution | 3D printing of materials. |
Impact | Presentation at academic conferences (TMS 2023 (USA)) and an academic publication is being written. |
Start Year | 2022 |
Description | Plastometrex and Korean Institute of Materials Science |
Organisation | Korea Institute of Materials Science |
Country | Korea, Republic of |
Sector | Academic/University |
PI Contribution | Drafting of international standard, know how on handling of anisotropic indentation profiles. |
Collaborator Contribution | Technical advice on standard drafting, assistance on addressing comments from other international experts, gathering international support from other standards bodies for ISO standardisation. |
Impact | Draft of an international standard. |
Start Year | 2023 |
Description | Plastometrex and NASA |
Organisation | National Aeronautics and Space Administration (NASA) |
Department | Glenn Research Center |
Country | United States |
Sector | Public |
PI Contribution | Mechanical testing (tensile, PIP and high temperature), data analysis, finite element simulations |
Collaborator Contribution | Provision of material used in rocket nozzle engines, and material under development to replace the current state of the art (both conventionally and additively manufactured). Insight into material usage, operating conditions and economics of material supply. |
Impact | NASA presentation on the results at the international conference on additive manufacturing. |
Start Year | 2022 |
Description | Plastometrex and the University of Limerick (Ireland) |
Organisation | University of Limerick |
Country | Ireland |
Sector | Academic/University |
PI Contribution | Access to equipment, testing, intellectual input and analysis of materials provided, giving new insights into the true mechanical properties of the material. |
Collaborator Contribution | Production of material and processing, data from conventional testing and intellectual input. |
Impact | Presentations at Academic conferences (ICAM 2022 (USA), TMS 2023 (USA)) Academic Publication that has been recently accepted, title Indentation Plastometry for Study of Anisotropy and Inhomogeneity in Maraging Steel produced by Laser Powder Bed Fusion (DOI not yet available) |
Start Year | 2022 |
Description | Renishaw |
Organisation | Renishaw PLC |
Country | United Kingdom |
Sector | Private |
PI Contribution | Testing of materials produced by Renishaw. Scoping and proposal for further collaborative work together, partnering with the National Physical Laboratory. Data analysis, case study drafting and new finite element modelling approaches. |
Collaborator Contribution | Supply of samples, know-how on how printing parameters used change the mechanical (anisotropic) response of the samples, joint promotion. |
Impact | Case Study on use of PIP for determining mechanical properties of additively manufactured products made by Renishaw |
Start Year | 2023 |
Description | AM-UK (Trade Body) Relaunch |
Form Of Engagement Activity | Participation in an activity, workshop or similar |
Part Of Official Scheme? | No |
Geographic Reach | National |
Primary Audience | Professional Practitioners |
Results and Impact | Almost 100 professionals attending the AM-UK relaunch, a trade body for additive manufacturing in the UK. There were lots of questions about the testing technology that was demonstrated and it resulted in a new collaboration. |
Year(s) Of Engagement Activity | 2022 |
Description | International Standards Meetings |
Form Of Engagement Activity | A formal working group, expert panel or dialogue |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Professional Practitioners |
Results and Impact | Attendance at the ASTM F42 and ISO TC 261 standards committee meetings with around 100 attendees. Along with collaborators at the Korea Institute of Materials Science, we are pursuing a joint ISO/ASTM standard for our new test method. Meetings to date: Penn State, USA, April 2023 Incheon, South Korea, September 2023 Upcoming Ohio State, USA, April 2024 |
Year(s) Of Engagement Activity | 2023,2024 |
Description | Materials Innovation Day |
Form Of Engagement Activity | Participation in an activity, workshop or similar |
Part Of Official Scheme? | No |
Geographic Reach | National |
Primary Audience | Industry/Business |
Results and Impact | An event hosted at the iAero centre in Yeovil jointly by Plastometrex and Leonardo. An industry event to connect with peers and discover how industry leaders like Leonardo drive efficiencies to stay ahead of the curve in material innovation |
Year(s) Of Engagement Activity | 2023 |
URL | https://www.weaf.co.uk/event/business-west-materials-innovation-day/ |
Description | Online Webinar for High throughput testing of Additively Manufactured materials |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Professional Practitioners |
Results and Impact | Webinar coving the current state of the art of the technology offering and current research challenges and future development. |
Year(s) Of Engagement Activity | 2022 |
Description | Webinar on Spatial Mapping of Mechanical Properties: Utilising PIP Testing in Additive Manufacturing |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Industry/Business |
Results and Impact | A webinar hosted with the University of Limerick, to promote the recent journal publication looking at inhomogeneity and anisotropy in additively manufactured parts. |
Year(s) Of Engagement Activity | 2023 |
URL | https://app.livestorm.co/plastometrex/spatial-mapping-of-mechanical-properties-utilising-pip-testing... |