Tribocorrosion Tests Research Articles

Research on the synergistic damage behavior of tribocorrosion of CoCrFeNi-X (Ti, Mn, Mo, Al) high-entropy alloys

This study investigates the damage behavior of CoCrFeNi-X (Ti, Mn, Mo, Al) high-entropy alloy coatings under reciprocating friction in a 3.5 wt% NaCl solution. Conventional tribocorrosion experiments and full-contact tribocorrosion tests were conducted to analyze the synergistic effects of corrosion and wear. Electrochemical analysis and surface characterization of the worn samples were performed to quantify the losses resulting from the synergistic effects in tribocorrosion. The results demonstrate a significant increase in the corrosion rate in the worn area by 2–3 orders of magnitude due to friction, accompanied by a notable potential difference between the wear scar region and the surrounding area. While corrosion products can reduce the friction coefficient, the localized damage induced by corrosion significantly enhances the wear volume.

Grain size effect on tribocorrosion kinetics in ultrahigh-purity magnesium

Tribocorrosion readily removes the protective corrosion product, creates new reactive corrosion sites and thus accelerates material loss in metallic materials. This is evidenced by a pronounced or gradual decline in open circuit potential (OCP) during tribocorrosion assessments. Here we report that grain refinement can not only enhance wear resistance in dry conditions, but also induce an anomalously stable OCP variation and fortify tribocorrosion resistance in ultrahigh-purity magnesium during tribocorrosion. The tribocorrosion tests revealed that the fine-grained Mg (FG-Mg) sample exhibited a wear rate (4.56 × 10−4 mm3/Nm) approximately half that of the coarse-grained Mg (CG-Mg) sample (7.87 × 10−4 mm3/Nm). CG-Mg showed a gradual OCP decrease, associated with a thin, unprotective tribocorrosion layer, even thinner than that resulting from dry sliding. Conversely, FG-Mg exhibited stable OCP evolution and quasi-linear tribocorrosion kinetics over time, attributed to a thick, protective tribocorrosion layer. Transmission electron microscopy data suggest that high-diffusivity pathways for oxygen along grain boundaries at the early tribocorrosion stages facilitate the formation of a continuous, protective MgO layer and an adjacent oxidized layer with a depth-dependent oxygen content gradient, enhancing tribocorrosion resistance in FG-Mg. Our findings offer valuable insights for strategically tailoring tribocorrosion resistance by modulating the OCP variation of highly active metals and alloys.

Corrosion and tribocorrosion resistance of superhydrophobic LPBF-NiTi alloys surface fabricated by nanosecond laser and ultrasonic fluorination

NiTi alloys have been extensively studied for their excellent super-elasticity (SE) and shape memory effects (SME). With the development of laser powder bed fusion (LPBF), it is possible to process the complex structure of NiTi alloy, which results in the mechanical properties of LPBF-NiTi alloys receiving great attention. However, the processing method is different from the traditional one, which not only has an impact on the mechanical properties but also seriously affects the anti-corrosion resistance and causes a substantial deterioration. In the research work of this paper, nanosecond laser processing was used to fabricate the bionic mastoid-shaped micro-nano structure on the LPBF-NiTi alloys. An efficient and convenient ultrasonic fluorination treatment was used to achieve the full surface coverage of FAS-17 in 10 min, and the superhydrophobic LPBF-NiTi alloy surface (CA ~ 157°) was successfully achieved. The constructed superhydrophobic LPBF-NiTi alloy surface exhibits excellent anti-corrosion resistance compared with the original surface, and the icorr from (4.42 ± 0.5) × 10−7 A·cm−2 reduced to (3.21 ± 0.5) × 10−9 A·cm−2. Meanwhile, the superhydrophobic surface showed outstanding stability in the 15-day immersion test n 3.5 wt% NaCl solution. And it is also stable after the tribocorrosion tests in 3.5 wt% NaCl solution at 1 N and 5 N pressures. The remarkable anti-corrosion resistance and stability of the superhydrophobic surface can be attributed to the micro-nano structure rich in the TiO2 oxide layer, the air layer formed by the superhydrophobic surface insulates the corrosive liquid and the stable hydrophobic agent film.

Effects of high-temperature and high-pressure immersion corrosion durations on the fretting tribo-corrosion behaviors of Inconel 690 alloy

An Inconel 690 alloy tube acting as a steam generator tube has been widely applied in the second and third generations of nuclear power plants using pressurized water reactors. However, its entire service process is always accompanied by high-temperature and high-pressure (HTHP) liquid medium corrosion and various fretting mechanical damage behaviors. This study first immerses the Inconel 690 alloy tube in HTHP corrosive medium for different lengths of time (0, 4, 8, and 12 h); then, a fretting tribo-corrosion test rig is used to investigate the effect of different fretting mechanical parameters on the surface damage mechanism and electrochemical dynamic response of each test sample. Results show that the corrosion rate of the Inconel 690 alloy tube has significantly increased after being treated by HTHP immersion corrosion, which is mainly due to the pre-existing corrosion products.

Tribocorrosion experimental investigation on Ti6Al4V burnished samples used for hip joint replacement

This work aimed to investigate the effect of the burnishing surface treatment on the tribocorrosion resistance related to Ti6Al4V specimens, in the framework of the head-neck tribo-pair characterising a total hip replacement. The experimental procedure carried out started by choosing the specimens referred to different burnishing conditions together with specimens not treated or treated only with the turning process. Then, tribocorrosion experiments with fixed load and two frequencies were conducted through a reciprocating tribometer equipped with a potentiostat able to measure the electrochemical corrosion potential and current associated to the synergistic wear phenomenon analysed together with the coefficient of friction. Furthermore, optical topographical acquisitions were performed before and after the experiments. The results showed that the non-burnished specimens exhibited unexpected oscillations of the coefficient of friction approximately in the middle of the rubbing phase and the same happens for the cell potential; the wear volume was measured after the tribocorrosion test. This allowed to estimate the wear factor related to all the analysed configurations, showing a greater mean value in correspondence of greater sliding frequencies in the non-burnished cases, while the opposite happens in the burnished cases. Finally, the burnished sample at the lower burnishing force resulted to have the noblest corrosion potential, while the non-burnished samples exhibited the lowest corrosion current density.

Macrophage proteomic analysis of covalent immobilization of hyaluronic acid and graphene oxide on CoCr alloy in a tribocorrosive environment.

In this work, a sequential covalent immobilization of graphene oxide (GO) and hyaluronic acid (HA) is performed to obtain a biocompatible wear-resistant nanocoating on the surface of the biomedical grade cobalt-chrome (CoCr) alloy. Nanocoated CoCr surfaces were characterized by Raman spectroscopy and electrochemical impedance spectroscopy (EIS) in 3 g/L HA electrolyte. Tribocorrosion tests of the nanocoated CoCr surfaces were carried out in a pin on flat tribometer. The biological response of covalently HA/GO biofunctionalized CoCr surfaces with and without wear-corrosion processes was studied through the analysis of the proteome of macrophages. Raman spectra revealed characteristic bands of GO and HA on the functionalized CoCr surfaces. The electrochemical response by EIS showed a stable and protective behavior over 23 days in the simulated biological environment. HA/GO covalently immobilized on CoCr alloy is able to protect the surface and reduce the wear volume released under tribocorrosion tests. Unsupervised classification analysis of the macrophage proteome via hierarchical clustering and principal component analysis (PCA) revealed that the covalent functionalization on CoCr enhances the macrophage biocompatibility in vitro. On the other hand, disruption of the HA/GO nanocoating by tribocorrosion processes induced a macrophage proteome which was differently clustered and was distantly located in the PCA space. In addition, tribocorrosion induced an increase in the percentage of upregulated and downregulated proteins in the macrophage proteome, revealing that disruption of the covalent nanocoating impacts the macrophage proteome. Although macrophage inflammation induced by tribocorrosion of HA/GO/CoCr surfaces is observed, it is ameliorated by the covalently grafting of HA, which provides immunomodulation by eliciting downregulations in characteristic pro-inflammatory signaling involved in inflammation and aseptic loosening of CoCr joint arthroplasties. Covalent HA/GO nanocoating on CoCr provides potential applications for in vivo joint prostheses led a reduced metal-induced inflammation and degradation by wear-corrosion.

Investigation on the tribocorrosion behavior of casting and spark plasma sintering Ni20Cr alloys in 3.5 wt% NaCl solution: Grain size effects

Tribocorrosion tests were performed on the Cast and SPS Ni20Cr alloys sliding against Si3N4 in 3.5 wt% NaCl solution to investigate the grain size effect on the synergy of corrosion and wear. An appealing result was that the SPS alloy with finer grains exhibited less intense corrosion-induced wear, but more severe wear-induced corrosion, compared to the coarse-grained Cast alloy. The mechanism responsible for the significant difference was attributed to the composition and microstructure of the tribo-layer influenced by grain refinement. The finer grain structure facilitated the rapid replenishment of thicker Cr-rich tribo-layer, while meanwhile the dense layer exhibited high hardness and greatly reduced the wear rate of SPS alloy.

Nodular defects aggravated tribocorrosion failure mechanism in Cr/GLC multilayer coatings for marine applications

Amorphous carbon coatings by various physical vapor deposition (PVD) have been widely attempted for enhancing both anti-wear and corrosion resistance of bulk materials used in harsh marine environments. However, PVD coatings are apt to be worn due to the existence of growth defects mostly like macro-size nodular particles. In this work, we deliberately fabricated the SiO2 nanoparticles with a size of 200 nm as nodular defects in Cr and graphite-like carbon (Cr/GLC) multilayer coatings, and the dependence of tribocorrosion behavior of coating on the nodular defects was focused by the comprehensively tribological and electrochemical tests. The results showed that introducing SiO2 nodular particles could not degrade the mechanical properties of Cr/GLC coating, but significantly accelerated both the abrasive wear in early sliding-stage under dry friction and the corrosive failure in chloride solution. Particularly, once the tribocorrosion tests in 3.5 wt.% NaCl solution were conducted for the Cr/GLC coating with nodular defects, the distinct ploughing damage originated from abrasive wear promoted the localized spallation of coatings, which thereafter enabled the easy water wedging along spallation for the substantial catastrophe of coatings. The present observations could evident the importance to fabricate the defect-free protective coatings required for harsh tribocorrosion applications.

Structural, mechanical and tribocorrosion behaviors of Mo-Ni-Si alloys

Mo-Ni-Si alloys were fabricated using arc melting, and their structural and tribocorrosion behaviors were investigated. The results revealed that the alloys have good comprehensive mechanical properties and tribocorrosion resistance with increasing Mo content. The alloys exhibit lower friction coefficients and wear rates owing to the creation of the MoO3-NiO-SiO2 passivation layer. The wear rates of the alloys were approximately one-tenth of that of 0Cr18Ni9. During the tribocorrosion tests, the OCP values of the alloys are inversely related to the friction coefficient, which is attributed to the synergistic effect of wear and corrosion. The main tribocorrosion mechanisms for Mo-Ni-Si alloys are pure wear and preferential tribocorrosion of the NiMo phase, whereas the wear loss of 0Cr18Ni9 is dominated by corrosion-induced wear.

Micro-arc and thermal oxidized titanium matrix composites for tribocorrosion-resistant biomedical implants

Superior tribocorrosion resistance is offered by titanium matrix composites (TMCs) compared to their unreinforced matrix metal, but bioactivity concerns are raised for biomedical applications. Simple methods such as micro-arc oxidation (MAO) and thermal oxidation (TO) are employed to enhance the bioactivity and degradation resistance of Ti. However, the impact of those surface treatments on TMC surfaces is poorly understood. Therefore, the present work aimed to explore the influence of MAO and TO treatments on the surfaces of in-situ Ti-TiB-TiC and ex-situ Ti-B4C composites, and to assess their corrosion and tribocorrosion performance. Corrosion and tribocorrosion tests were conducted in phosphate-buffered saline solution (PBS) at body temperature. Electrochemical assays were performed by means of potentiodynamic polarization scans while additional potentiostatic tests were performed for the untreated ex-situ composites. Tribo-electrochemical assays were conducted under open circuit potential (OCP) and under normal loads of 0.5 and 10 N against a 10 mm diameter alumina ball in a reciprocating ball-on-plate tribometer. Results revealed reinforcement detachments in ex-situ composites after both treatments. This was primarily attributed to oxide layer growth at the reinforcement/reaction zone interface. Hence, the use of MAO and TO on ex-situ Ti-B4C composites may not be appropriate for biomedical applications, mainly because the B4C particles tend to detach during the treatment. In contrast, TO-treated in-situ composites displayed excellent combination of corrosion and tribocorrosion performance, even under elevated applied loads, mainly due to the existence of the oxygen diffusion zone (ODZ) beneath the oxide surface produced by TO, together with the more stable electrochemical properties observed during steady-state conditions.

Investigating the Roles of Protein on the Cobalt Alloy Surface Degradation for Biomedical Implant Through Tribocorrosion Mechanisms

Previous investigation has established the formation of tribofilm is influenced by tribochemical reactions between the electrolyte and the articulating surface of cobalt alloy through sliding tests in various simulated fluids. Although it has successfully characterized the film composition via spectroscopy analysis and indicated to have impact on material loss, a comprehensive understanding of the material degradation mechanism in tribocorrosion condition was still lacking. Therefore, this study aims to investigate the role of protein in the tribocorrosive degradation of cobalt-chromium-molybdenum (CoCrMo) alloy in different simulated physiological electrolytes. Using a similar testing protocol, tribocorrosion tests were conducted with reciprocating ceramic ball against CoCrMo samples immersed in saline and culture medium, compared to both electrolytes diluted with 25% fetal bovine serum (FBS). Synergistic and mechanistic approaches were employed to model the tribocorrosive degradation. Results reveal that protein plays a beneficial role in reducing corrosive (electrochemical) surface degradation under tribocorrosion condition, whilst increasing mechanical wear degradation in the process. Despite studies have shown that tribocorrosion behavior in metal alloys is highly influenced by the presence of organic matter, this study provides a more clarity of the roles played by protein in tribocorrosive degradation on CoCrMo surface as its novel finding.

Research on the construction of gradient nanostructure and anti-tribocorrosion behavior of aluminum alloy surface

Gradient nanostructure in aluminum alloy, constructed via a two-dimensional ultrasonic surface burnishing process, displays enhanced tribocorrosion resistance in artificial seawater. Corrosion tests are undertaken to understand the influence of gradient nanostructure on corrosion resistance, and crystal plasticity finite element models are developed to examine wear resistance. Tribocorrosion tests are performed through wear tests in the artificial seawater environment. The results indicate that the processed samples' corrosion rate decreases from 3.12 × 10−2 mm/a to 2.45 × 10−3 mm/a. The wear scar sizes of the processed samples are approximately half the unprocessed samples. The gradient nanostructure obstructs dislocation glide during wear, diminishes the accumulation shear, and promotes high-hardness corrosion product formation, effectively isolating the direct contact between the friction pairs, thus improving the tribocorrosion resistance.

Tribocorrosion behavior of martensitic stainless cutlery steel in pressed Shanghai Bok Choy

The martensitic stainless cutlery steel is frequently exposed to conditions where there were both wear and corrosion in the daily usage of kitchen cutlery. To understand the degradation mechanism of the cutlery steel under practical application environments, tribocorrosion tests were performed on 60Cr16MoMA martensitic stainless steel (MSS) in 3.5 wt% NaCl solution and pressed Shanghai Bok Choy (pSBC). The results revealed that compared with 3.5 wt% NaCl solution, the 60Cr16MoMA steel exhibited better tribocorrosion resistance in pSBC during sliding. Through analysis of cross-sectional wear track profiles, it was found that the 60Cr16MoMA steel had the least volume loss when tested in pSBC. High performance liquid chromatography-mass spectrometry results showed that flavonoids and ascorbic acid were present in pSBC, which may act as corrosion inhibitors and stabilize the passive film through physisorption or chemisorption. X-ray photoelectron spectrometer results further confirmed that the passive film formed in pSBC was more stable due to higher Fe2+/Fe3+ and Cr2O3/Cr(OH)3 ratios. These findings further confirm the MSS are subjected to the hazards of wear, corrosion and tribocorrosion, and provide important empirical and theoretical support for evaluating cutlery steel volume loss in practical application environments in the future.

In situ production of low-modulus Ti-Nb alloys by selective laser melting and their functional assessment toward orthopedic applications.

This work aimed to manufacture Ti-28.5Nb and Ti-40.0Nb (wt%) alloys in situ via selective laser melting (SLM) from Ti and Nb elemental powders. X-ray diffraction analysis revealed complete β-phase (cubic) in Ti-40.0Nb and a mixture of (α'' orthorhombic + β cubic) phases in Ti-28.5Nb were formed, whereas few of the Nb particles remained only partially fused during manufacturing. The fraction of partially melted Nb particles was determined as ∼2 and ∼18% in Ti-28.5Nb and Ti-40Nb, respectively. Mechanical characterization revealed higher hardness and more strength in Ti-28.5Nb than in Ti-40.0Nb due to the presence of the α'' phase in the former. Tribocorrosion tests reveal a significantly better wear-corrosion resistance for Ti-40.0Nb, as determined from a lower total volume loss in Ti-40.0Nb (∼2 × 10-4 mm-3) than in Ti-28.5Nb (∼13 × 10-2 mm-3). The lower volume loss and better corrosion resistance behavior are attributed to the β phase, which was dominant in Ti-40.0Nb. Cell studies reveal no toxicity for up to 7 days. Both the alloys were better at supporting cell proliferation than wrought Ti6Al4V. This study presents a route to preparing Ti-Nb alloys in situ by SLM that are promising candidates for biomedical applications.

Effects of carbon doping on microstructure, electrochemical and tribo-corrosion performances of biocompatible TiZrNbTaMoCxNy coatings

To improve the longevity of medical devices in physiological environments, a series of TiZrNbTaMoCxNy coatings were fabricated on 316L stainless steel using RF magnetron sputtering. The work demonstrated that appropriate carbon doping can effectively enhance the density, electrochemical properties, and resistance to tribo-corrosion of the coatings. Among the tested samples, coating S4 with a carbon content of 24 at. % exhibited the lowest wear rate (6.496 × 10−7 mm3 N−1 m−1) during the tribo-corrosion tests, due to its favorable lubrication characteristic (COF = 0.127) and enhanced resistance to plastic deformation (H3/E2 = 0.78 Gpa). Additionally, coating S5 with a carbon content of 28 at. % showed superior electrochemical performance (icorr = 5.21 × 10−8 A), attributed to its higher coating density and ability to form passive films. Both S4 and S5 exhibited superior biocompatibility compared to 316L.

The electrochemical and tribocorrosion behavior of hybrid ceramic film-coated Ti alloys

In this study, anodic TiO2 ceramic coating was formed on titanium alloys produced by SLM by using the anodization method. After then, hybrid ceramic coatings are produced by combining a formation of ZrO2 nanostructures in the TiO2 coating with the SILAR technique. The microstructure, wettability, electrochemical properties, and tribocorrosion behavior of anodic TiO2 and hybrid ceramic coatings were also investigated. According to XRD results, two TiO2 peaks are observed in anodic TiO2 films. After the SILAR process, the tetragonal-ZrO2, and monoclinic-ZrO2 with TiO2 peaks were obtained in the hybrid ceramic coatings. Especially, while the intensity of the TiO2 peaks decreased, the intensity of the ZrO2 peaks increased with the increase in cycle time. The surface wettability experiments indicate that the HB-80 specimen exhibits superhydrophobic behavior, and it also has the highest contact angle value among all specimens. Corrosion tests in SBF solution confirmed that hybrid ceramic films importantly increased the anticorrosion performance of anodic TiO2 film, depending on the cycle times owing to filling the pores, and the best outcomes for corrosion resistance were obtained from the HB-80 specimen owing to its superhydrophobic properties. Moreover, the results of tribocorrosion tests revealed that all hybrid ceramic films displayed higher tribocorrosion resistance than anodic TiO2 ceramic film and uncoated Ti6Al4V substrate, and the best performance was seen from the HB-80 specimen due to its decreased porosity and the direct contact area between pin and surface.

Replacing Toxic Hard Chrome Coatings: Exploring the Tribocorrosion Behaviour of Electroless Nickel-Boron Coatings

Electroless nickel-boron coatings present outstanding properties such as high hardness, excellent wear resistance and uniform coating, and thus they are considered to be alternative to toxic hard chrome coatings. However, they contain lead that is toxic and used as stabilizer in the plating bath. This study aims to investigate the tribocorrosion behaviour of lead-free electroless nickel-boron coatings. In the present research, several tests were carried out to investigate the behaviour of these coatings under both dry and tribocorrosion reciprocating sliding wear against alumina balls, at room temperature. The open circuit potential (OCP) method was used to determine the degradation mechanism of the coatings. The results of the tribocorrosion and dry wear tests showed that the performance of coatings was very different from each other. A steady state for the coefficient of friction (COF) is achieved during the tribocorrosion test, whereas the constant production of debris and their presence in the contact implied an increase in COF with distance during the dry wear test. The wear mechanisms of these coatings also presented variations in these tests. It was found that the wear area calculated from tribocorrosion is lower (56 µm2) than the one from dry sliding test (86 µm2).

Tribocorrosion behaviors of VNbMoTaWCr high entropy alloy coatings

In this work, four BCC-structured VNbMoTaW and VNbMoTaWCr high entropy alloy (HEA) coatings with different Cr contents were fabricated on the surface of 304 stainless steel (304SS) plates by a pulsed DC magnetron sputtering system. In addition to the dry pin-on-disk wear test and pure corrosion test, two kinds of tribocorrosion tests were performed. For the tribocorrosion test without applied potential, the HEA coatings were immersed in a 3.5 wt% NaCl aqueous solution at room temperature under 1 N load using a pin-on-disk tribometer. For the tribocorrosion test with applied potentials, the potentiodynamic polarization test was conducted to investigate the effects of external potentials and sliding loads on the corrosion current density, polarization resistance, and wear rates of HEA coatings. The hardness, corrosion resistance, and tribocorrosion (without applied potential) resistance of VNbMoTaWCr HEA coatings increased with increasing Cr content. The VNbMoTaWCr coatings with higher than 24.7 at.% Cr had a high hardness of 16.4 to 16.5 GPa and excellent corrosion resistance in pure corrosion and tribocorrosion without applied potential. On the other hand, as the tribocorrosion was executed with an applied potential higher than the breakdown potential and high current density, the tribocorrosion resistance of HEA coatings was greatly influenced by its protection degradation ratio, Pdr (the polarization resistance ratio between pure corrosion and tribocorrosion setup 2). Finally, the lowest wear rate of 2.55 × 10−5 mm3N−1 m−1, which was 1.4 times better than 304SS, was obtained for the VNbMoTaWCr coating containing 11.65 at.% Cr after the tribocorrosion test with applied high potential because of its lower Pdr value and less decay of corrosion protection ability.

Polypyrrole zinc-doped film deposited on a plasma-treated surface improves the tribocorrosion behavior of titanium dental implant material

Polypyrrole (PPy) films have shown attractive electrochemical properties and promising implant applications when electrodeposited on plasma electrolytic oxidation (PEO) surfaces. Although the PEO + PPy surface demonstrates excellent mechanical and electrochemical performance, there are no reports on the effects of combined corrosion and mechanical interactions, which simulates the oral environment. In addition, since implant failures may be related to deficiencies in the osseointegration process, the electrodeposition of zinc (Zn) on the coating can promote an osteogenic substrate. Therefore, we aimed to investigate the tribocorrosion behavior of PEO-treated surfaces coated with PPy films with and without Zn and whether such PPy films affect the cellular response of MG-63 human osteoblast-like cells. Titanium discs with machined and PEO-modified surfaces were considered as controls. The experimental groups used PEO surfaces followed by electrodeposition of PPy (PEO + PPy) and PPy and Zn (PEO + PPy/Zn). The surfaces' physical-chemical properties were assessed. The tribocorrosion tests were run under free potential and potentiostatic (anodic and cathodic potentials) conditions using a pin-on-disk tribosystem simulating the oral environment (load = 1 N, stroke = 2 mm, number of cycles = 2000). Electrochemical impedance spectroscopy was performed before and after tribocorrosion to analyze the changes in corrosion kinetics. Worn areas were observed using white-light-interferometry and scanning electron microscopy. For in vitro cell experiments, the viability, number of live/dead cells, adhesion ability, and mineralization property of cells were evaluated. Our outcomes revealed that PPy films improved tribocorrosion performance by exhibiting more positive OCP values and slight fluctuation and variation of the current value during the sliding phases. In general, due to the films' morphology and “cushion effect”, PPy films enhanced the surface resistance against corrosion and wear, indicating a low total weight loss (Kwc) and wear-corrosion degradation mechanism. The PEO + PPy/Zn surface was cytocompatible, enhancing the cell adhesion and proliferation on the surface. Overall, PPy films represent a promising coating to improve the stability and lifetime of biomedical implants.

Friction and tribocorrosion behavior of Fe-Cr-B alloys manufactured by laser directed energy deposition

The current assessment of tribocorrosion in alloys for mining machinery repair is insufficient. This study explored four Fe-Cr-B alloys with similar compositions but varying hardness. Dry and wet (water) friction tests align with the hardness hierarchy, indicating enhanced wear resistance with higher hardness. However, tribocorrosion tests yield diverse results. Notably, High-hardness alloys (JG-11# and 431) had many boride phases, displaying corrosion pits, leading to early corrosion failure. Low-hardness alloys (JG-3#) had fewer boride phases, indicating friction-dominated failure. Balancing both hardness and corrosion resistance, the alloy (JG-8#) demonstrates excellent tribocorrosion performance while ensuring the absence of micro corrosion pits.