All Outputs (58)

Modelling the influence of plasticity induced softening on the low cycle fatigue and crack propagation behaviour of a nickel-based superalloy (2023)
Journal Article

Cyclic hysteresis loops generated during high-temperature, isothermal, low-cycle fatigue testing of the nickel-based superalloy RR1000 revealed a gradual decrease in elastic modulus of up to 25 % compared to the initial value in dependence of the acc... Read More about Modelling the influence of plasticity induced softening on the low cycle fatigue and crack propagation behaviour of a nickel-based superalloy.

The Estimation of Taylor-Quinney Coefficients Using Small Ring Specimens (2022)
Journal Article

Background: The use of the Taylor-Quinney coefficient for introducing a thermal dissipation term into material models relies on understanding its dependencies. These are usually determined through extensive experimentation, wherein temperature variat... Read More about The Estimation of Taylor-Quinney Coefficients Using Small Ring Specimens.

Failure modes in dual layer thickness Laser Powder Bed Fusion components using a novel post-mortem reconstruction technique (2022)
Journal Article

To exploit the design freedoms of Powder Bed Fusion, parameters can be varied within sub-volumes of components to achieve the optimal part for both service conditions and manufacturing productivity. This involves prioritising mechanical strength in a... Read More about Failure modes in dual layer thickness Laser Powder Bed Fusion components using a novel post-mortem reconstruction technique.

On the thermomechanical aging of LPBF alloy 718 (2022)
Journal Article

Heat treatment of products post additive manufacture are considered hugely important since the metallurgical condition post process is suboptimal. In the case of nickel-based superalloys, grain size, precipitate distribution and precipitate size are... Read More about On the thermomechanical aging of LPBF alloy 718.

Numerical Investigation into the Influence of Grain Orientation Distribution on the Local and Global Elastic-Plastic Behaviour of Polycrystalline Nickel-Based Superalloy INC-738 LC (2022)
Journal Article

Polycrystalline nickel-based superalloys tend to have large grains within component areas where high loads are dominant during operation. Due to these large grains, caused by the manufacturing and cooling process, the orientation of each grain become... Read More about Numerical Investigation into the Influence of Grain Orientation Distribution on the Local and Global Elastic-Plastic Behaviour of Polycrystalline Nickel-Based Superalloy INC-738 LC.

On the use of multiple layer thicknesses within laser powder bed fusion and the effect on mechanical properties (2021)
Journal Article

Laser Powder Bed fusion is capable of rapid production of parts, from conception, compared with traditional manufacturing methods. This said, the time taken to fabricate a single part can still be significant – typically many hours. Processing thicke... Read More about On the use of multiple layer thicknesses within laser powder bed fusion and the effect on mechanical properties.

A computationally efficient method for the prediction of fretting wear in practical engineering applications (2021)
Journal Article

A method for simulating fretting wear using the Modified Simplex Method for a contact solution has been developed. The initial separation between two contacting bodies was used as an input to solve the contact force distribution. An average cycle pre... Read More about A computationally efficient method for the prediction of fretting wear in practical engineering applications.

Thermomechanical fatigue life due to scatter in constitutive parameters (2021)
Journal Article

For critical component application, such as aerospace turbine rotors, it is imperative to be able to make accurate in-service material behaviour and component life predictions for both design and monitoring of component life. The development of such... Read More about Thermomechanical fatigue life due to scatter in constitutive parameters.

Small specimen techniques for estimation of tensile, fatigue, fracture and crack propagation material model parameters (2021)
Journal Article

Small specimen mechanical testing is an exciting and rapidly developing field in which fundamental deformation behaviours can be observed from experiments performed on comparatively small amounts of material. These methods are particularly useful whe... Read More about Small specimen techniques for estimation of tensile, fatigue, fracture and crack propagation material model parameters.

Machine learning to determine the main factors affecting creep rates in laser powder bed fusion (2021)
Journal Article

There is an increasing need for the use of additive manufacturing (AM) to produce improved critical application engineering components. However, the materials manufactured using AM perform well below their traditionally manufactured counterparts, par... Read More about Machine learning to determine the main factors affecting creep rates in laser powder bed fusion.

Powder Bed Fusion of nickel-based superalloys: A review (2021)
Journal Article

Powder Bed Fusion (PBF) techniques constitute a family of Additive Manufacturing (AM) processes, which are characterised by high design flexibility and no tooling requirement. This makes PBF techniques attractive to many modern manufacturing sectors... Read More about Powder Bed Fusion of nickel-based superalloys: A review.

Interlaced layer thicknesses within single laser powder bed fusion geometries (2021)
Journal Article

The geometrical design freedoms associated with additive manufacturing techniques are currently well exploited and finding commercial application. The capability of layer-based processes to allow modification of composition and microstructure in proc... Read More about Interlaced layer thicknesses within single laser powder bed fusion geometries.

Multi-laser scan strategies for enhancing creep performance in LPBF (2021)
Journal Article

Laser Powder Bed Fusion (LPBF) enables complex structures to be manufactured, which is attractive to industries where augmented service performance can be achieved. However, the build time of LPBF can be slower than traditional manufacturing processe... Read More about Multi-laser scan strategies for enhancing creep performance in LPBF.

The creep behaviour of nickel alloy 718 manufactured by laser powder bed fusion (2021)
Journal Article

Components manufactured by laser powder bed fusion (LPBF) are limited by their performance for use in critical applications. LPBF materials have microstructural defects, such as suboptimal grain size and morphology, and macroscale anomalies, such as... Read More about The creep behaviour of nickel alloy 718 manufactured by laser powder bed fusion.

On the use of small ring testing for the characterisation of elastic and yield material property variation in additively manufactured materials (2020)
Journal Article

© 2020 Elsevier B.V. The present work introduces a small volume, high throughput testing method that may be used to quickly, and with high spatial fidelity, investigate local material properties in additively manufactured materials. A case study appl... Read More about On the use of small ring testing for the characterisation of elastic and yield material property variation in additively manufactured materials.

A review of non-destructive testing techniques for the in-situ investigation of fretting fatigue cracks (2020)
Journal Article

© 2020 The Authors Fretting fatigue can significantly reduce the life of components, leading to unexpected in-service failures. This phenomenon has been studied for over a century, with significant progress being made during the past decade. There ar... Read More about A review of non-destructive testing techniques for the in-situ investigation of fretting fatigue cracks.

DevTMF – Towards code of practice for thermo-mechanical fatigue crack growth (2020)
Journal Article

© 2020 Elsevier Ltd The current paper presents work on identification and evaluation of a range of factors influencing accuracy and comparability of data generated by three laboratories carrying out stress-controlled thermo-mechanical fatigue crack g... Read More about DevTMF – Towards code of practice for thermo-mechanical fatigue crack growth.

The prediction of crack propagation in coarse grain RR1000 using a unified modelling approach (2020)
Journal Article

© 2020 Elsevier Ltd The polycrystalline nickel-base superalloy RR1000 is used as turbine rotor material in Rolls-Royce aero engines and has to withstand a wide variety of load and temperature changes during operation. In order to maximize the potenti... Read More about The prediction of crack propagation in coarse grain RR1000 using a unified modelling approach.

Potential difference methods for measuring crack growth: A review (2020)
Journal Article

© 2020 Elsevier Ltd Non-destructive testing techniques are widely applied in industry for the evaluation of quantities of interest without inflicting additional damage accumulation. Crack detection and monitoring is a prime example of where non-destr... Read More about Potential difference methods for measuring crack growth: A review.

A viscoelastic – viscoplastic material model for superalloy applications (2020)
Journal Article

© 2020 Elsevier Ltd An understanding of rate dependency over a wide range of time scales is vitally important in approximating the transient response of critical components operating in extreme environments. Many examples of viscoplastic model formul... Read More about A viscoelastic – viscoplastic material model for superalloy applications.