Short answer

When designing with additively manufactured titanium alloys for corrosive environments, account for the significant impact of as-produced surface topography on performance and consider post-processing to achieve consistent results.

Field: Final Production
Source: Metals (2020)
Method: Comparative experimental analysis
Evidence: Moderate effect

The as-produced surface topography of additively manufactured Ti-6Al-4V parts, while offering unique shapes for biomedical applications, leads to less predictable and potentially inferior corrosion resistance in simulated body fluid compared to conventionally processed materials. This final production research insight is drawn from a 2020 study published in Metals. Using Comparative experimental analysis, researchers explored how this design variable affects real-world outcomes. The key design takeaway: When designing with additively manufactured titanium alloys for corrosive environments, account for the significant impact of as-produced surface topography on performance and consider post-processing to achieve consistent results.

Study

Final ProductionHigh ImpactModerate effect

As-produced additive manufactured Ti-6Al-4V exhibits variable corrosion resistance compared to wrought material

Metals · 2020

Key Findings

01As-produced EBM and DMLS Ti-6Al-4V parts exhibit different microstructures and surface topographies compared to wrought material.
02Additively manufactured parts show more complex and variable electrochemical behavior than wrought material.
03Mechanically polished additively manufactured parts demonstrate similar electrochemical performance to each other but retain some instability compared to polished wrought material.

Application

Design takeaway

How to apply

When selecting materials for implantable devices, evaluate the as-produced surface finish of additively manufactured components and its potential impact on long-term stability. Consider post-processing techniques like polishing or coating to mitigate risks associated with surface variability.

Project actions

01When comparing manufacturing methods, always consider the 'as-produced' state and its implications.
02Investigate how surface finish affects material properties relevant to the product's intended use.

Method & Evidence

AimTo investigate the relationship between the surface topography of as-produced Electron Beam Melting (EBM) and Direct Metal Laser Sintering (DMLS) Ti-6Al-4V parts and their corrosion resistance in a simulated body fluid, comparing them to wrought material.

MethodComparative experimental analysis

ProcedureSpecimens of Ti-6Al-4V were produced using EBM and DMLS, alongside wrought material. Metallographic, crystallographic, and topographic analyses were conducted on both as-produced and mechanically polished surfaces. Electrochemical properties were assessed using potentiodynamic polarization tests in a simulated body fluid.

ContextBiomedical device manufacturing, additive manufacturing of titanium alloys

Variables

IV["Manufacturing method (EBM, DMLS, wrought)","Surface condition (as-produced, polished)"]

DV["Corrosion resistance (electrochemical behavior)","Surface topography","Microstructure"]

CV["Material (Ti-6Al-4V)","Simulated body fluid composition","Testing temperature"]

Strengths & Limitations

Strengths

+Direct comparison of as-produced AM parts with wrought material.
+Multi-faceted analysis including metallographic, crystallographic, topographic, and electrochemical properties.

Limitations

The study used a simulated body fluid, which may not perfectly replicate the complex biological environment. Only two additive manufacturing methods were compared.

Reliability & validity

The use of standardized electrochemical testing methods enhances the reliability of the corrosion resistance data. The comparison across multiple analytical techniques (metallography, topography, electrochemistry) strengthens the validity of the findings regarding the relationship between surface and performance.

Think critically

To what extent can design choices mitigate the inherent surface variability of additive manufacturing processes in critical applications?

Design Principles

"Surface topography directly influences material performance in its operating environment."

For designers and engineers working with titanium alloys in demanding environments like biomedical implants, understanding the as-produced surface characteristics is crucial. The inherent variability in additive manufacturing processes can significantly impact long-term performance and patient safety, necessitating careful consideration of post-processing or material selection.

What This Means for Your Design

3D printed titanium parts have rougher surfaces than traditionally made ones, which can affect how they behave in the body. Polishing helps, but the 3D printed parts can still be a bit unpredictable.

How to use in your project

1.Reference this study when discussing the trade-offs between different manufacturing methods for metal components, particularly concerning surface finish and performance.

Add to My Project

Quick Cite

Paragraph starter

This research by Acquesta and Monetta (2020) demonstrates that the as-produced surface topography of additively manufactured Ti-6Al-4V parts, generated via EBM and DMLS, leads to variable electrochemical behavior in simulated body fluid compared to wrought material. This suggests that for critical applications, post-processing to achieve a consistent and predictable surface finish is essential.

Source

Metals

As-Built EBM and DMLS Ti-6Al-4V Parts: Topography–Corrosion Resistance Relationship in a Simulated Body Fluid

journal · 2020

View source

Questions About This Research

What does the research say about as-produced additive manufactured ti-6al-4v exhibits variable corrosion resistance compared to wrought material?: When designing with additively manufactured titanium alloys for corrosive environments, account for the significant impact of as-produced surface topography on performance and consider post-processing to achieve consistent results. Evidence: Metals (2020).
Why does "As-produced additive manufactured Ti-6Al-4V exhibits variable corrosion resistance compared to wrought material" matter for design?: For designers and engineers working with titanium alloys in demanding environments like biomedical implants, understanding the as-produced surface characteristics is crucial. The inherent variability in additive manufacturing processes can significantly impact long-term performance and patient safety, necessitating careful consideration of post-processing or material selection.
How can designers apply this research?: When designing with additively manufactured titanium alloys for corrosive environments, account for the significant impact of as-produced surface topography on performance and consider post-processing to achieve consistent results.
What were the main findings?: As-produced EBM and DMLS Ti-6Al-4V parts exhibit different microstructures and surface topographies compared to wrought material.. Additively manufactured parts show more complex and variable electrochemical behavior than wrought material.. Mechanically polished additively manufactured parts demonstrate similar electrochemical performance to each other but retain some instability compared to polished wrought material.
What research method was used?: Comparative experimental analysis.
How strong is the evidence?: Evidence strength is rated Moderate effect, based on a 2020 journal from Metals.
What should I do differently in my next project?: When selecting materials for implantable devices, evaluate the as-produced surface finish of additively manufactured components and its potential impact on long-term stability. Consider post-processing techniques like polishing or coating to mitigate risks associated with surface variability.
What are the limitations?: The study focused on a specific simulated body fluid and may not represent all physiological conditions. The range of AM parameters tested was limited.