Bhanupratap Gaur, Samrat Sagar, Chetana M. Suryawanshi, Nishant Tikekar, Rupesh Ghyar and Ravi Bhallamudi
Ti6Al4V alloy patient-customized implants (PCI) are often fabricated using laser powder bed fusion (LPBF) and annealed to enhance the microstructural, physical and mechanical…
Abstract
Purpose
Ti6Al4V alloy patient-customized implants (PCI) are often fabricated using laser powder bed fusion (LPBF) and annealed to enhance the microstructural, physical and mechanical properties. This study aims to demonstrate the effects of annealing on the physio-mechanical properties to select optimal process parameters.
Design/methodology/approach
Test samples were fabricated using the Taguchi L9 approach by varying parameters such as laser power (LP), laser velocity (LV) and hatch distance (HD) to three levels. Physical and mechanical test results were used to optimize the parameters for fabricating as-built and annealed implants separately using Grey relational analysis. An optimized parameter set was used for fabricating biological test samples, followed by animal testing to validate the qualified parameters.
Findings
Two optimized sets of process parameters (LP = 100 W, LV = 500 mm/s and HD = 0.08 mm; and LP = 300 W, LV = 1,350 mm/s and HD = 0.08 mm) are suggested suitable for implant fabrication regardless of the inclusion of annealing in the manufacturing process. The absence of any necrosis or reaction on the local tissues after nine weeks validated the suitability of the parameter set for implants.
Practical implications
To help PCI manufacturers in parameter selection and to exclude annealing from the manufacturing process for faster implant delivery.
Originality/value
To the best of the authors’ knowledge, this is probably a first attempt that suggests LPBF parameters that are independent of inclusion of annealing in implant fabrication process.
Details
Keywords
Sanjay Sitaram Phadnis and Mukul Kulshrestha
The quantity and quality of available water resources have been recognized limiting factors in development of most of the arid and semi arid regions. The purpose of this paper is…
Abstract
Purpose
The quantity and quality of available water resources have been recognized limiting factors in development of most of the arid and semi arid regions. The purpose of this paper is to evaluate the efficiency, for water users' associations (WUA), of irrigation project Samrat Ashok Sagar (Halali) in India, using benchmarking by data envelopment analysis as the performance evaluation tool and to integrate the outcome of the benchmarking process for planning, design and effective management of available water resources.
Design/methodology/approach
To collect information or data required to calculate indicators, there was personal interaction with water users and executive engineers in‐charge of the project, and competent authority for WUA (sub‐engineers), with other technical staff and with establishment staff and the purpose of the study explained. In the analysis, the performance gap was compared within the scheme. The causes of the performance gap and the action required for closing the performance gap were explored. Data envelopment analysis was done for different sets of input output by input‐oriented model through software. The data collected were real time and validated from Samrat Ashok Sagar Irrigation and Drainage Project Authority.
Findings
It was found that the majority of WUAs as per model I to model VI had efficiency below 70 per cent, which is a matter of serious concern. It is evident that considerable variations occur amongst the various WUAs in terms of the operational characteristics reflected by the independent variables.
Originality/value
The paper demonstrates that it is evident that considerable variations occur amongst the various WUAs in terms of the operational characteristics reflected by the independent variables.
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The purpose of this study is to investigate the effects of entropy generation of some embedded thermophysical properties on heat and mass transfer of pulsatile flow of…
Abstract
Purpose
The purpose of this study is to investigate the effects of entropy generation of some embedded thermophysical properties on heat and mass transfer of pulsatile flow of non-Newtonian nanofluid flows between two porous parallel plates in the presence of Lorentz force are taken into account in this research.
Design/methodology/approach
The governing partial differential equations (PDEs) were nondimensionalized using suitable nondimensional quantities to transform the PDEs into a system of coupled nonlinear PDEs. The resulting equations are solved using the spectral relaxation method due to the effectiveness and accuracy of the method. The obtained velocity and temperature profiles are used to compute the entropy generation rate and Bejan number. The influence of various flow parameters on the velocity, temperature, entropy generation rate and Bejan number are discussed graphically.
Findings
The results indicate that the energy losses can be minimized in the system by choosing appropriate values for pertinent parameters; when thermal conductivity is increasing, this leads to the depreciation of entropy generation, and while this increment in thermal conductivity appreciates the Bejan number, the Eckert number on entropy generation and Bejan number, the graph shows that each time of increase in Eckert will lead to rising of entropy generation while this increase shows a reduction in Bejan number. To shed more light, these results were further demonstrated graphically. The current research was very well supported by prior literature works.
Originality/value
All results are presented graphically, and the results in this article are anticipated to be helpful in the area of engineering.