Processing Beta Titanium Alloys in Powder-Based Additive Manufacturing
Lead Research Organisation:
University of Sheffield
Department Name: Materials Science and Engineering
Abstract
Advanced Metallic Systems CDT Project
Additive Manufacturing (AM) is a novel near-net-shape fabrication technique used to produce solid components by consolidating layers of powder, or wires or ribbons, by partial or full melting. The materials to be deposited are melted by a focussed heat source, provided by an electron beam (e-beam), laser, or plasma or welding arc. Each layer is a 2D section from a final 3D CAD component model i.e., the 3D geometry of a component is formed by building-up a stack of 2-D profiles, layer-by-layer, by local melting.
Much of the hype surrounding additive manufacturing technologies has been made around advanced designs; however, a significant value proposition exists to manufacture materials in ways which are only able to be exploited using advanced microstructure control mechanisms. Additive manufacturing offers a unique way of microstructure control with a high degree of design freedom. In order to use this in design, a better understanding of process parameters influence on the microstructure during build is required. This project will use experimental and modelling techniques to understand and optimise the effects of processing parameters of parts manufactured from beta titanium alloys.
Additive Manufacturing (AM) is a novel near-net-shape fabrication technique used to produce solid components by consolidating layers of powder, or wires or ribbons, by partial or full melting. The materials to be deposited are melted by a focussed heat source, provided by an electron beam (e-beam), laser, or plasma or welding arc. Each layer is a 2D section from a final 3D CAD component model i.e., the 3D geometry of a component is formed by building-up a stack of 2-D profiles, layer-by-layer, by local melting.
Much of the hype surrounding additive manufacturing technologies has been made around advanced designs; however, a significant value proposition exists to manufacture materials in ways which are only able to be exploited using advanced microstructure control mechanisms. Additive manufacturing offers a unique way of microstructure control with a high degree of design freedom. In order to use this in design, a better understanding of process parameters influence on the microstructure during build is required. This project will use experimental and modelling techniques to understand and optimise the effects of processing parameters of parts manufactured from beta titanium alloys.
Planned Impact
The CDT in Advanced Metallic Systems will help to address the shortage of research and development specialists in metallic materials by helping to expand the talent pool and by acting as an advocate for the discipline to encourage future generations into the sector.
Reviews by EPSRC [1,2], UK government and industry [3,4] have recognised that solving the worldwide shortage of expertise in this field is critical to the UK's future outlook as an advanced manufacturing economy. Manufacturing in metallic materials currently contributes £18 billion of added value, employs over 404,000 people in the UK and businesses sell £38 billion of metals into the manufacturing supply chain [5,6]. Metallic materials are vital to high-value manufacturing across all sectors including transport, energy, renewables, healthcare, food production, and construction. Companies across all of these sectors (many of whom are world-leaders) are dependent on metallic materials in the manufacture of their products.
Advanced materials manufacturing processes are also key enabling technologies underpinning innovation [7]. There are many exciting emerging innovations in metals manufacturing under development, such as 3D printing, or additive manufacturing, laser machining etc., that will underpin the future competitiveness of UK high added-value manufacturing [8]. To simply maintain current numbers, the metals manufacturing industry will need to recruit 3200 new professional material scientists and engineers between 2010 and 2016 [9].
As well as addressing this shortfall, the CDT will also impact directly on the companies with which it collaborates, on the wider high value manufacturing sector and on the UK economy as a whole, as follows:
1. Collaborating companies, across a wide range of businesses in the supply chain including SMEs' and research organisations will benefit directly from the CDT through:
- Targeted projects in direct support of their business and its future development and competitiveness.
- Access to the expertise and facilities of the host institutions.
- Involvement in the training of the next generation of potential employees with advanced technical and leadership skills who can add value to their organisations.
2. The UK High-Value added Manufacturing Community will benefit as the CDT will:
- Develop the underpinning science and advanced-level knowledge base required by future high technology areas, where there is high expectation of gross added value.
- Provide an enhanced route to exploitation, by covering the full spectrum of technology readiness levels.
- Ensure dissemination of knowledge to the sector, through student-led SME consultancy projects and continuous professional development courses.
3. The wider UK economy will benefit as the CDT will:
- Promote materials science and engineering and encourage future generations to enter the field, through outreach activities developed by the students to increase awareness of the discipline and its key contribution to many technologies we now take for granted and its importance to future innovation.
- Develop and exploit new technologies and products which will help to maintain a competitive UK advanced manufacturing sector, ensure an internationally competitive and balanced UK economy for future generations and contribute to technical challenges in key societal issues such as energy, sustainability and health care.
1. EPSRC Materials International Review 2008
2. EPSRC Materially Better Call 2013
3. Materials UK Structural Materials Report, 2009
4. A Review of Light alloys technology and recommendations for MOD research. Dstl/CR13675 V2.0, 2005
5. Materials UK Structural Materials Report, www.matuk.co.uk, 2009
6. The Metals Sector Skills & Performance Strategy Report, 2005
7. Materials for Key Enabling Technologies, EMRS, 2011
8. Landscape for the future of high value manufacturing, TSB, 2012
9. Semta Labour Market Intelligence Factsheet Metals, 2010
Reviews by EPSRC [1,2], UK government and industry [3,4] have recognised that solving the worldwide shortage of expertise in this field is critical to the UK's future outlook as an advanced manufacturing economy. Manufacturing in metallic materials currently contributes £18 billion of added value, employs over 404,000 people in the UK and businesses sell £38 billion of metals into the manufacturing supply chain [5,6]. Metallic materials are vital to high-value manufacturing across all sectors including transport, energy, renewables, healthcare, food production, and construction. Companies across all of these sectors (many of whom are world-leaders) are dependent on metallic materials in the manufacture of their products.
Advanced materials manufacturing processes are also key enabling technologies underpinning innovation [7]. There are many exciting emerging innovations in metals manufacturing under development, such as 3D printing, or additive manufacturing, laser machining etc., that will underpin the future competitiveness of UK high added-value manufacturing [8]. To simply maintain current numbers, the metals manufacturing industry will need to recruit 3200 new professional material scientists and engineers between 2010 and 2016 [9].
As well as addressing this shortfall, the CDT will also impact directly on the companies with which it collaborates, on the wider high value manufacturing sector and on the UK economy as a whole, as follows:
1. Collaborating companies, across a wide range of businesses in the supply chain including SMEs' and research organisations will benefit directly from the CDT through:
- Targeted projects in direct support of their business and its future development and competitiveness.
- Access to the expertise and facilities of the host institutions.
- Involvement in the training of the next generation of potential employees with advanced technical and leadership skills who can add value to their organisations.
2. The UK High-Value added Manufacturing Community will benefit as the CDT will:
- Develop the underpinning science and advanced-level knowledge base required by future high technology areas, where there is high expectation of gross added value.
- Provide an enhanced route to exploitation, by covering the full spectrum of technology readiness levels.
- Ensure dissemination of knowledge to the sector, through student-led SME consultancy projects and continuous professional development courses.
3. The wider UK economy will benefit as the CDT will:
- Promote materials science and engineering and encourage future generations to enter the field, through outreach activities developed by the students to increase awareness of the discipline and its key contribution to many technologies we now take for granted and its importance to future innovation.
- Develop and exploit new technologies and products which will help to maintain a competitive UK advanced manufacturing sector, ensure an internationally competitive and balanced UK economy for future generations and contribute to technical challenges in key societal issues such as energy, sustainability and health care.
1. EPSRC Materials International Review 2008
2. EPSRC Materially Better Call 2013
3. Materials UK Structural Materials Report, 2009
4. A Review of Light alloys technology and recommendations for MOD research. Dstl/CR13675 V2.0, 2005
5. Materials UK Structural Materials Report, www.matuk.co.uk, 2009
6. The Metals Sector Skills & Performance Strategy Report, 2005
7. Materials for Key Enabling Technologies, EMRS, 2011
8. Landscape for the future of high value manufacturing, TSB, 2012
9. Semta Labour Market Intelligence Factsheet Metals, 2010
| Description | The current key finding of this project is the process development of ß21S titanium alloy for electron beam melting methods using the Arcam Q10+ system. ß21S titanium is an alloy primarily used in aerospace exhaust components and is not currently widely produced using powder based additive manufacturing methods where there is industry interest in doing so. There are a number of process parameters that can be changed on the Arcam systems. Through several trials, the plate heat and preheat themes in the system have been developed to work with ß21S titanium alloy (adjusted from the default themes on the machine designed for Ti-6Al-4V). These themes are important parameters in creating a stable sintered powder bed for the build to be melted on. Using the initial developed themes, simple geometries and lattices were successfully built with the powder. Optical microscopy images of the structures were taken and from that porosity levels were measured and some of the samples have seemingly acceptable levels of porosity (meaning low enough to possible fix through post process heat treatment, although that will need to be tested). This is an initial indication that the alloy is suitable for the process and further development is required to test how much control over the printed material can be achieved. A series of numerical analysis has also been done on the material using ThermoCalc and Matlab software to predict thermal response of the alloy. Data from practical work were compared against initial numerical analysis, changes can later be made to the numerical analysis to develop a more accurate prediction model for the alloy, |
| Exploitation Route | The developed themes can be put to use for manufacturers looking to print using ß21S titanium alloy. The work will give a good indication of what process parameters should be used for this material. After further development it may even be possible to use the results to aid printing with the material for parts with specific requirements for microstructure and therefore properties. The development of processing parameters for ß21S titanium alloy also gives understanding to how the process can be adapted to print beta titanium alloys in general. The resulting process themes can be a starting point for others researching and developing similar alloys. |
| Sectors | Aerospace, Defence and Marine,Manufacturing, including Industrial Biotechology |