Surface generation on titanium alloy through powder-mixed electric discharge machining with the focus on bioimplant applications

Abstract

The inflammation around poorly osseointegrated bioimplant is one of the root causes of its failure. Therefore, the biomedical industry constantly strives for new ways to develop bioactive surfaces in permanent implants to enhance the service life. In this regard, implant surface modification at micro/nanoscales is carried out to enrich substrate with higher engineering attributes and biocompatibility. Considering the complexities of post-processing of implants, this study evaluates the potentiality of an integrated process of implant machining and surface modification, namely, powder-mixed electric discharge machining (PMEDM). Ti6Al4V ELI implant material, as substrate, is machined under two distinct (Si, SiC) mixed additive conditions using a full factorial design of experiments. The surface quality, surface morphology, recast layer depth, surface chemistry, and work hardening have been holistically investigated. The bioactivity analysis of machined surfaces shows more porosity in the case of Si powder particles (200 to 400 nm) compared to SiC (100 to 250 nm). Furthermore, the study optimized the process parameters for minimum roughness and recast layer depth considering 5 g/L powder concentration, 5A pulse current, 50 µs pulse on time for Si, and 100 µs pulse on time for SiC. A comprehensive review of surface features based on process physical science is established, and nanoscale surface topography influencing protein absorption is analyzed.

Electric Discharge Machining of Ti6Al4V ELI in Biomedical Industry: Parametric Analysis of Surface Functionalization and Tribological Characterization

“…During the process, no direct contact exists between the tool electrode and the workpiece; therefore, no residual stresses are produced. The process requires the tool and workpiece to be immersed in a dielectric liquid [ 6 ]. The machined surface contains random features such as craters and porosity, and has improved mechanical properties because of the surface treatment [ 7 , 8 , 9 , 10 ].…”

“…In this regard, the machining challenges associated with the material are thoroughly explored in this research, which considers a wide range of process parameters such as pulse current, pulse ON time, pulse OFF time, and polarity. A SiC-mixed dielectric was used based on the recommendations of Farooq et al [ 6 ] for machining titanium alloy. Similarly, Mughal et al [ 8 ] recommended using a SiC-mixed dielectric for improved surface integrity and related attributes.…”

Helical Milling of CFRP/Ti6Al4V Stacks Using Nano Fluid Based Minimum Quantity Lubrication (NF-MQL): Investigations on Process Performance and Hole Integrity

“…The workpiece was cross-sectioned after each experiment to measure the roughness precisely. A surface texture meter (Surtronic S-128) by Taylor Hobson Precision UK was used to measure the surface roughness (Ra, as it is the most commonly used in industry) of holes [ 34 ]. The surface texture meter had a gauge range of 300 mm, a resolution of 0.01 mm, a traverse length of 0.25–25 mm, and a diamond stylus with a cut-off length of 0.80 mm and an evaluation length of 4 mm.…”

Achieving effective interlayer bonding of PLA parts during the material extrusion process with enhanced mechanical properties

“…Multi-objective optimization was used to reduce the quantity of materials needed for the structural support, lowering material costs, and increasing work efficiency 7 . The reuse of 3D printed items also contributes significantly to decreasing environmental issues.…”