Tribocorrosion Assessment of Laser Clad Ceramic Reinforced TI6Al4V Surface Composites

Summary

Assessing the wear resistance, microhardness, and corrosion resistance of composites with ceramic reinforcement particles (Zr/TiC and Ti/TiC systems) in conditions relevant to biomedical implants (NaCl/H₂SO₄).

Abstract

This article presents a comprehensive experimental protocol for evaluating the tribocorrosion behavior of additively manufactured TI₆Al₄V based composites reinforced with ceramic phases using laser metal deposition (LMD). This protocol addresses the need to understand the synergistic degradation mechanisms that arise in components exposed to mechanical loading and corrosive environments in biomedical and aerospace applications. The protocol includes controlled laser cladding of TI₆Al₄V with Zr/TiC and Ti/TiC reinforcements, followed by detailed microstructural, mechanical, electrochemical, and tribocorrosion characterization. The procedures cover powder handling, substrate preparation, laser processing, metallographic preparation, microscopy, X–ray diffraction, microhardness testing, electrochemical corrosion measurements, and tribocorrosion testing using a reciprocating ball–on–plate tribometer under electrochemical control in a NaCl/H₂SO₄ electrolyte. This method enables real-time assessment of wear–corrosion interactions, including passive film breakdown and re–passivation under sliding conditions, while accounting for additive manufacturing-induced microstructural features. The protocol serves as a standardized framework for evaluating the effectiveness of ceramic reinforcement strategies in improving the functionality of additively manufactured metallic systems intended for challenging environments.

Introduction

Laser surface modification incorporating ceramic phases is an effective approach to enhance the surface performance of metallic implants, enabling the formation of corrosion–resistant and mechanically reinforced coatings via laser metal deposition (LMD)¹. Titanium alloy TI₆Al₄V is widely used in biomedical implants due to its biocompatibility, high strength–to–weight ratio, and corrosion resistance^2,3. Nevertheless, it remains vulnerable to corrosion and tribocorrosion in aggressive physiological environments, where mechanical wear and el....

Protocol

1. Materials, equipment, and starting powders

1. Starting powders
   1. Obtain gas atomized TI₆Al₄V powder (ASTM F136) with a particle size range of 15–53 µm, zirconium (Zr) powder with ≥99.5 wt% purity and particle size of 10–45 µm, and titanium carbide (TiC) powder with ≥99 wt% purity and particle size of 2–10 µm.
   2. Store all powders in sealed containers under a dry argon atmosphere to prevent oxidation and moisture uptake prior to processing.
2. Substrate preparation
   1. Cut TI₆Al₄V substrate plates to dimens....

Results

Powder and substrate characterization
Representative scanning electron microscopy (SEM) micrographs of the starting reinforcement powders ((A) Ti, (B) Zr, and (C) TiC) are shown in Figure 1. The Images illustrate typical particle morphologies obtained from gas atomized and commercially sourced powders. Titanium and zirconium particles predominantly exhibited spherical to near spherical shapes, whereas titanium carbide (TiC) particles displayed more angul.......

Discussion

This methods article presents a reproducible protocol for the fabrication, characterization, and tribocorrosion evaluation of additively manufactured TI₆Al₄V based composites reinforced with ceramic phases using laser metal deposition (LMD). The methodology integrates powder characterization, automated in situ mixing, laser cladding, microstructural analysis, electrochemical testing, and coupled tribocorrosion assessment to address the complex degradation mechanisms encountered by titanium .......

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
Raw Materials / Powders
Ti6Al4V Powder			Gas-atomized, 15–53 μm (ASTM F136) Use in Study: Matrix material for laser cladding and substrate.
Zirconium (Zr) Powder			Purity ≥99.5 wt.%, 10–45 μm Use in Study: Composite reinforcement  and stabilizer material.
Titanium Carbide (TiC) Powder			Purity ≥99 wt.%, 2–10 μm Use in Study: Ceramic reinforcement material for composite.
Ti/TiC Powder			Blended composite powder (specific weight ratios) Use in Study: Reinforcement blend for composite.
Zr/TiC Powder			Blended composite powder (specific weight ratios) Use in Study: Reinforcement blend for composite.
Gases & Chemicals
Nitrogen (N2)			Controlled environment/Safety precaution Use in Study: Controlled environment for powder mixing and Laser Metal Deposition (LMD) system.
Argon (Ar)			Purging environment, Carrier/Shielding Gas Use in Study: Powder loading, LMD atmosphere, and coaxial nozzle with carrier gas.
Acetone			Cleaning solvent Use in Study: Cleaning of Ti6Al4V substrate.
Ethanol			Cleaning solvent Use in Study:
Cooling Solution			water Use in Study: Cleaning of Ti6Al4V substrate.
Transparent Epoxy Resin			Mounting material Use in Study: Mounting specimens for electrode or metallographic preparation.
Conductive Epoxy			Mounting material Use in Study: Mounting Specimens for Microscopy (Post-Sectioning)
Emery Paper (SiC)			Various grit sizes Use in Study: Grinding samples (metallographic preparation).
Diamond Paste			Polishing compound Use in Study: Polishing the exposed surfaces of electrodes and cross-sections.
Simulated Body Fluid (SBF)			Electrolyte Use in Study: Electrochemical corrosion testing.
NaCl/H2SO4 Electrolyte			Unspecified concentration Use in Study: Electrochemical corrosion testing.
Equipment & Instrumentation
Scanning Electron Microscope (SEM)			With Energy Dispersive Spectroscopy (EDS) Use in Study: Characterization of powders and substrates, microstructural analysis, reinforcement dispersion, and EDS mapping.