Plasma Enhanced Magnetron Sputtering Research Articles

Influence of hexamethyldisilazane vapor on the structure and mechanical properties of TiC-based coatings

Silicon-modified titanium carbide (TiC) coatings exhibit excellent properties and are attractive for a variety of protective coating applications. These coatings are often produced by sputtering silicon from elemental or composite targets, which limits both large area compositional uniformity and the ability to grade silicon composition to improve coating adhesion. Here we demonstrate the use of an organosilicon vapor, hexamethyldisilazane (HMDS), as a silicon source during the plasma enhanced magnetron sputtering (PEMS) of TiC-based coatings. Three coatings, with compositionally graded interlayers, were deposited under various HMDS flow rates onto silicon and stainless steel substrates. The growth structures of the coatings were characterized by scanning electron microscopy and atomic force microscopy. The introduction of HMDS under low flow conditions resulted in an increase in root-mean-square surface roughness from 13 to 41 nm, however, the coating was characterized by a similar columnar growth structure as produced without HMDS flow. At higher HMDS flow, columnar growth was disrupted due to the segregation of sufficient amounts of silicon and excess carbon. Coating composition, as determined by energy dispersive X-ray spectroscopy, indicates that the densification of the growth structure occurred at titanium, silicon, and carbon contents of 29, 9, and 57 at.%, respectively. X-ray diffraction analysis demonstrated that all coatings contained rock-salt structure phases (TiC, TiCN) with 〈111〉 out-of-plane texture. Raman spectroscopy and X-ray photoelectron spectroscopy confirmed the presence of amorphous phases, consisting primarily of silicon and excess carbon (a-C:H/a-SiCx:H), in both coatings produced with HMDS. The simultaneous disruption of columnar growth and formation of a composite microstructure consisting of crystalline and amorphous phases at high HMDS flow resulted in improved mechanical properties when compared to the TiC control coating, evidenced by an increase in the H/E ratio from 0.063 to 0.10. The processing methods demonstrated here may potentially be applied to industrial settings for improved compositional control during the introduction of silicon to TiC-based coatings.

Plasma-enhanced magnetron sputtering of silver nanoparticles on reverse osmosis membranes for improved antifouling properties

The reverse osmosis process is an efficient water purification technology with comparatively low energy consumption. However, unwanted biofilm formation remains a major challenge for membrane plant operators, and effective fouling control strategies are highly sought for. A material-based antifouling approach is the deposition of silver nanoparticles onto the polyamide layer of thin film composite membranes by plasma-enhanced magnetron sputtering, as described in this study. The particle size and distributions were analyzed from Scanning Electron Microscopy (SEM) images and discussed with the elemental composition of the membrane surfaces derived by X-ray Photoelectron Spectroscopy (XPS). The desalination efficiency of the silver coated membranes was determined by use of a coupon tester, and the antimicrobial effect was verified by inducing a reproducible microbial stress on the membranes with a chemostat. In the presence of silver nanoparticles, which had an average diameter of 30 nm, the biofilm formation of pseudomonas sp. was significantly reduced by 64.6% on average after 14 days of continuous cultivation. A sputtering time of 5 s proved to be successful both in significantly improving the antifouling properties as well as fully maintaining the filtration performance of the membranes.

Evaluation of the adhesion and failure mechanism of the hard CrN coatings on different substrates

The CrN coatings were performed on 316 L austenitic stainless steel, skh51 high speed steel, and YG8 cemented carbide using plasma-enhanced magnetron sputtering system. The adhesion and failure mechanism of the hard CrN coatings on different kinds of substrates were investigated. The morphology, microstructure, crystallinity, as well as nano-hardness and Young' modulus of the as-deposited coatings were investigated by scanning electron microscopy, X-ray diffraction, and nano-indentation testing system, respectively. In particularly, the adhesion and failure mechanism of different coating-substrate systems were evaluated by scratch and indentation tests. Apparently, the adhesion and failure mechanism of the CrN coatings were significantly influenced by the species of substrates. The results of the scratch test indicated that the increase of adhesion strength (Lc = 190 N) of the CrN coating to YG8 was associated with the formation of the obvious indented coating-substrate interface, and the higher modulus of the substrate, which provided a better load-carrying capacity, whereas the CrN coating deposited on 316 L in contrast. In Rockwell indentation test, the main failure mechanism of the CrN coatings on substrate with high modulus were mainly brittle fracture, whereas the CrN coatings deposited on soft substrate was failed in ring cracks, which was attributed to the asynchronous recovery between the substrate and the coating.

Effect of substrate bias current on structure and properties of CrNx films deposited by plasma enhanced magnetron sputtering

In order to further improve the mechanical properties of CrN films, the influence of substrate bias current on the microstructure and properties of the CrNx films deposited by plasma enhanced magnetron sputtering was studied by scanning electron microscopy, energy dispersive spectroscopy, X-ray diffraction, 3D profiler, nano indenter, and ball-on-disk tribometer. With the increase of substrate bias current, the microstructure of the films is transformed from a dendritic structure into a super dense columnar structure, and the phase composition is evolved from Cr → Cr + Cr2N → pure Cr2N. When the substrate bias current is >1.5 A, the preferred orientation is transformed from Cr2N(111) to Cr2N(300) with increasing substrate bias current. The surface roughness of the films is decreased from 27.3 to 18.7 nm as the substrate bias current is increased from 0.1 to 1.5 A, but the surface roughness remains nearly unchanged when the substrate bias current exceeds 1.5 A. The hardness and effective Young's modulus of the films are obviously increased with increasing the substrate bias current from 0.1 to 3.0 A, while they are almost independent of the substrate bias current when the substrate bias current is no less than 3.0 A. The lowest friction coefficient of 0.43 is obtained when the substrate bias current is 4.5 A. When the substrate bias current is increased, the wear rate of CrN-coated samples is first increased and then decreased, and the lowest wear rates is 4.6 × 10−16 m3/(N·m) when the substrate bias current is 6.0 A.

Numerical estimation of intrinsic stress in physical vapor deposited thin-films

A method of numerically estimating intrinsic stress has been developed for thin-film coatings of TiSiCN prepared by plasma enhanced magnetron sputtering at 280°C. A portable optical setup was designed to be used with a commercial lab microscope, for taking measurements of the radii of curvature of the coated samples. The sensitivity of the optical instrument was optimized for taking measurements over a specific range of radii. A finite element model was developed in Abaqus to computationally determine the intrinsic and residual stresses in the thin films, with the help of the optical measurements. The computationally generated stresses and curvatures were found to agree well with previous analytical work. An average intrinsic stress of −2.49GPa was observed for the thin-film samples. The stress relief in all the samples was calculated to be in the range of (20−30) %. Variations in the intrinsic and residual stress in the coatings indicate the possibility of a non-uniform deposition incidence based on their substrate positions.

Tribocorrosion behavior of low friction TiSiCN nanocomposite coatings deposited on titanium alloy for biomedical applications

The quaternary Ti-Si-C-N nanocomposite is regarded to be promising one in the biomedical field due to its improved tribocorrosion performance and biocompatibility. The deposition of such material on biomedical components surfaces can extend its lifespan by minimizing wear debris and ion releasing inside the physiological environment. Therefore, this work investigates the tribocorrosion behavior of low friction Ti-Si-C-N nanocomposite coatings applied on the ASTM F136 titanium alloy immersed in a phosphate-buffered solution (PBS). The coatings were obtained by the plasma-enhanced magnetron sputtering (PEMS) technique using an assorted precursor flow range of tetramethylsilane (TMS) and hexamethyldisilazane (HMDSN) liquid along with acetylene (C2H2) gas. Reciprocal sliding tribocorrosion tests were performed under PBS solution on the samples and compared to a Ti-6Al-4V bare alloy sample. The microstructure, morphology, chemical structure, mechanical properties, and adhesion of the coated samples were also evaluated. The results presented an expressive reduction of at least 97% in the wear rate of the low friction Ti-(Si)-C-N nanocomposite coatings compared to the titanium bare alloy sample. The tribocorrosion performance of the coated samples demonstrated a strong correlation within the Silicon and Carbon content presented on coatings chemical compositions. As consequence, the roles of nanocrystallites refinement, the presence of amorphous carbon region and the oxides generation were demonstrated as relevant characteristics to improve the tribocorrosion behavior of Ti-Si-C-N nanocomposite.

Carbon-encapsulated metal nanoparticles deposited by plasma enhanced magnetron sputtering

Carbon-encapsulated gold nanoparticles (CEGNs) were synthesized by plasma enhanced magnetron sputtering using C2H2 and Ar mixtures as the precursor. The morphology, microstructure and optical property of the CEGNs were characterized using TEM, SEM, and UV–Vis absorption spectrum. The results show that the gold NPs with narrow size distribution ranging from 7 nm to 20 nm were encapsulated by amorphous carbon nanospheres. The fraction of C2H2 in the gas mixture of C2H2 and Ar seemed to have a significant influence on the gold particle size and distribution of the as-made CEGNs. As the fraction of the C2H2 increased from 5% to 10%, the average particle size decreased from about 13 nm to 7 nm and the carbon nanospheres with single gold NPs core evolved to the carbon chain with multi-cores. In addition, carbon-encapsulated silver nanoparticles (CESNs) were also prepared by the same method. This indicates that the plasma enhanced magnetron sputtering may be one of the best ways for the deposition of the carbon-encapsulated metal nanoparticles (CEMNs). The UV–Vis absorption spectra of the CEGNs and CESNs reveal strong absorption bands due to the surface plasma resonance of the nanoparticles, implying that the as-made CEMNs could be applied in optical limiting devices.

A comparative study of thick TiSiCN nanocomposite coatings deposited by dcMS and HiPIMS with and without PEMS assistance

As one version of high power impulse magnetron sputtering (HiPIMS) technique, deep oscillation magnetron sputtering (DOMS) generates large oscillation high power pulses to achieve a high fraction of metallic ions of the target species for arc-free reactive HiPIMS sputtering. Plasma enhanced magnetron sputtering (PEMS), an advanced version of conventional dc magnetron sputtering (dcMS), generates an extremely high flux of low energy gas ions with hot filament thermionic emission to produce an extra global plasma in the deposition system. As compared to conventional dcMS, both DOMS and PEMS aim at utilizing a highly ionized plasma to improve the structure and properties of the coatings. To gain a better understanding of the advantages and limits of these techniques, we present a comparative study for the thick TiSiCN nanocomposite coatings (15 μm) deposited using dcMS and DOMS with and without the PEMS assistance. The time averaged ion energy distributions of the plasmas generated by these techniques for TiSiCN coating depositions were characterized using an electrostatic quadrupole plasma mass spectrometer (EQP). The microstructure and mechanical properties of the coatings were characterized using X-ray diffraction, scanning electron microscopy, scratch test and nanoindentation. The microstructure, residual stress, and mechanical properties of the coatings were linked to the plasma properties and discussed in details. It is clear that the PEMS assistance significantly improves the microstructure and mechanical properties of the coatings produced by either dcMS or DOMS along with residual stress reduction.

Tribocorrosion behavior of DLC-coated Ti-6Al-4V alloy deposited by PIID and PEMS + PIID techniques for biomedical applications

One of the main drawbacks observed from the usage of titanium alloys implants is the premature failures due to excessive wear and corrosion. Among the surface modification alternatives, Diamond-like carbon (DLC) coatings appear as a promisor candidate, since it has an amorphous structure chemically inert with desirable properties and still is a solid lubricant. Dense DLC coatings on biomaterials could be obtained by advanced vapor deposition techniques as the plasma immersion ion deposition (PIID) and the plasma enhanced magnetron sputtering (PEMS). This work aims to investigate the tribocorrosion behavior of DLC coatings systems, obtained by PIID only and PEMS+PIID hybrid techniques, applied on Ti-6Al-4V alloy samples for biomedical applications. The tribocorrosion tests were performed under phosphate-buffered saline (PBS) solution on the DLC-coated samples and compared to a Ti-6Al-4V bare alloy sample. Besides tribocorrosion tests, it were performed X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, scanning electron microscopy (SEM), nanoindentation and scratch tests to evaluate the microstructure, morphology, mechanical properties and adhesion of the DLC-coated samples, respectively. The tribocorrosion tests demonstrated at least 5 times less friction coefficient and less than 2% of wear rate DLC-coated samples compared to Ti-6Al-4V bare alloy sample. Nevertheless, the results show that DLC coatings deposited by the advanced plasma enhanced techniques are very promissory to improve tribocorrosion behavior in Ti-6Al-4V alloy implants.

Microstructure and Mechanical Properties of Ti(Cr)SiC(O)N Coatings Deposited by Plasma Enhanced Magnetron Sputtering

TiSiCN, TiSiCON, TiCrSiCN, TiCrSiCON, CrSiCN and CrSiCON coatings have been deposited on WC-Co substrates and Si wafers using plasma enhanced magnetron sputtering (PEMS) technique. The microstructure, composition and mechanical properties of the non-oxygen coatings and oxygen-containing coatings were studied by XRD, SEM, EDS and load-depth-sensing indentation. The tribological behavior of the coatings against Al 2 O 3 balls was conducted by pin-on-disc tests. The results show that TiSiCON, TiCrSiCON and CrSiCON coatings exhibit the face center cubic (fcc) TiN-type (or CrN-type) structure. The existence of oxygen will induce loose structure and more defects for TiSiCON, TiCrSiCON and CrSiCON coatings compared with TiSiCN, TiCrSiCN and CrSiCN, respectively. The addition of oxygen element would lead to the decrease of the hardness ( H ) and elasticity of Ti(Cr)SiCN coatings. TiCrSiCON and CrSiCON coatings with oxygen element have lower friction coefficients and wear rate compared with TiCrSiCN and CrSiCN coatings without oxygen, respectively. The TiSiCON with higher friction coefficient and wear rate shows poor abrasive wear resistance than TiSiCN.

Effect of the filament discharge current on the microstructure and performance of plasma-enhanced magnetron sputtered TiN coatings

Titanium nitride (TiN) coatings were synthesized by plasma-enhanced magnetron sputtering (PEMS) on 316L austenitic stainless steel and YG8 cemented carbide substrates. The plasma enhancement process involved the use of hot filaments as additional sources of electrons for the magnetron discharge. The structural, morphology, crystallinity, thickness, abrasion resistance and adhesion of the TiN coatings, as well as the nanohardness and Young's modulus were investigated at different filament discharge currents. The results showed that with increasing discharge current, the deposition rate of the coating decreased, the structural morphology of the TiN coatings became finer and denser and the columnar grain size decreased. The critical load for failure in scratch adhesion tests of the coatings on stainless steel and YG8 substrates were over 22 N and 141 N, respectively. The nanohardness and Young's modulus both improved significantly from 8 GPa and 200 GPa to 38 GPa and 500 GPa, respectively, after the discharge current increased from 6 A up to 12 A. The adhesion and the abrasion resistance of the coating on cemented carbide increased, and those on stainless steel decreased, with increasing filament discharge current. It was found that matching the Young's modulus of the coating to that of the substrate was important to improve the adhesion and abrasion resistance of the coating. The results demonstrate that TiN coatings can be prepared by PEMS at appropriate filament discharge currents, resulting in coatings with uniform thickness, dense structure and high hardness, abrasion resistance and adhesion.

Silicon Gradients-containing Films for Mid- high Temperature Non-vacuum Solar Absorber Coatings

A new tandem absorber coating for mid-high temperature solar collectors mainly consists of a stress buffer layer Cr2O3, an infrared reflective layer Ag, a diffusion barrier layer Cr2O3, a silicon-based absorbing layer, including p-Si, μc-Si, nc-Si, α-Si, and an anti-reflection layer SiO2 is designed. Plasma enhanced magnetron sputtering (PEMS) and high temperature chemical vapor deposition (HTCVD) are combined in one chamber to prepare this solar selective coating which is expected to be air-stable and able to operate at mid- high temperatures (300-500°C) and also exhibit good spectral selectivity, thermal stability and oxidation resistance, so that it could be suited for solar power generation. This coating achieved a solar absorptance of 0.82-0.59 in the wavelength range of 0.3-0.7μm, while in the wavelength of 0.3-2.5μm the solar absorptance only reached 0.61-0.35. Amorphous silicon and silver structure are dominant in this tandem layer and no diffraction peaks of Cr2O3 and SiO2 were observed. Thermal stability tests indicate that this tandem absorber is stable after annealing in air at 500°C for 1h.

Tribological performance of quaternary CrSiCN coatings under dry and lubricated conditions

This paper presents an experimental study of friction and wear performance of quaternary CrSiCN coatings deposited on a hardened H-13 steel substrate by a plasma enhanced magnetron sputtering (PEMS) technique. Friction and wear tests were conducted with a reciprocating line contact between a hardened 4370 steel roller and coated and uncoated flat specimens under dry and lubricated conditions. The effects of coating thickness (1, 3.5 and 7.5µm) on the mechanical properties, friction and wear performance were also assessed. In dry sliding, the friction of coated surfaces was about the same as for uncoated surfaces, except for the 1-µm coating, which had higher friction. Friction for coated surfaces under lubricated contact was in general higher than for uncoated surfaces. There was no measurable wear on any of the coated surfaces, under either dry or lubricated conditions. However, wear was higher on the steel roller counterface sliding against the coated surfaces, with the amount of wear proportional to the mating coating thickness. The effectiveness of formulated lubricant additives was also modified by the coating, resulting in major effects on friction and wear behavior. This reduction in lubricant additive efficacy is due to the fact that the additives were designed and optimized for ferrous surfaces.

Synthesis of c-axis oriented AlN thin films at room temperature

In this study, aluminium nitride (AlN) thin films were synthesised by plasma-enhanced reactive DC magnetron sputtering on glass and Si (100) substrates and the effect of bias voltages on the structural, optical and morphological properties of the coatings has been studied. According to the grazing angle XRD studies, AlN in hexagonal (wurtzite) structure has been obtained for all the coatings. (002) plane c-axis oriented films have been achieved at 150 and 175 V bias voltages. AFM analyses demonstrated that with the increase in the bias voltages, a transformation from coarse to fine granular morphology has been occurred and smoother surfaces with a decrease in the surface roughness from 3.40 nm to about 1.90 nm were obtained. The results also demonstrated that the high transmittance values of AlN films were not affected by the change in the bias voltages and about 80% of transmittance obtained for all AlN films deposited in this study.

Structure and properties of GLC films deposited by PEMS

In this paper, an unbalanced plasma enhanced magnetron sputtering system was adopted to deposit four types of the graphite-like carbon (GLC) films under different currents of ion source. The results show that a moderate Ar+ bombardment effectively adjusts the content of sp3 hybrid structure, and significantly improves the film’s compactness. With the increase of ion source current, the hardness, H/E and H3/E2 ratios of the film present a change rule of increasing first and decreasing subsequently, and all achieve their maximum values under the ion source current of 10 A. Moreover, the average values of the studied GLC films are all below 0.05 with slight fluctuation, while the wear rate of the film presents a significant difference with the increase of ion source current. Especially, when the ion source current is 10 A, the friction coefficient and the wear rate of the GLC films are 0.01 and 1.7 × 10−16 m3 N−1 m−1, respectively, presenting excellent tribological properties.

Development and evaluation of low friction TiSiCN nanocomposite coatings for piston ring applications

Abstract To minimize the frictional losses and wear of piston rings in an automotive engine, thick low friction TiSiCN nanocomposite coatings have been developed. The coatings were deposited by sputtering titanium targets in argon, nitrogen, hexamethyldisilazane (HMDSN), and acetylene (C 2 H 2 ) using plasma enhanced magnetron sputtering (PEMS). The substrates were AISI 304 stainless steel coupons and piston rings with bore diameters of 137 mm and 86 mm. The elemental composition and microstructure of the coatings were optimized by varying the HMDSN and C 2 H 2 flow rates separately to achieve a combination of excellent adhesion, good mechanical properties, low coefficient of friction (COF) and wear rate. The optimized TiSiCN coatings exhibited a typical nanocomposite structure which showed excellent adhesion and dry COF in the range of 0.17 to 0.2 using a ball-on-disk tribometer. The tribological performance of the coated piston rings was evaluated using Plint TE77 tests in SAE 10W-30 diesel engine oil. The TE77 tests showed a 10% reduction in the COF (0.058) of the optimized coating compared to the uncoated baseline (0.065) at test conditions of 20 Hz, 30 N, and 25 mm stroke length. Finally, the coated rings were evaluated in a single cylinder gasoline engine using SAE 5W-20 engine oil and in a heavy duty diesel engine using 4.1% sooted SAE 10W-30 diesel engine oil. The gasoline engine test showed that the uncoated piston rings contributed 25% to 34% of the frictional loss in two separate baseline engine tests. In contrast, the coated rings contributed to 18% of the total frictional loss in the engine test. The diesel engine durability test showed a 28% and 40% lower ring weight loss for the coated top and second rings, respectively, as compared to the uncoated baseline. In addition, the cylinder liner, which was not coated, showed an average 50% lower wear than that in the uncoated baseline engine test.

Process controllability of inductively coupled plasma-enhanced reactive sputter deposition for the fabrication of amorphous InGaZnOx channel thin-film transistors

The process controllability of inductively coupled plasma-enhanced reactive sputter deposition for the fabrication of amorphous InGaZnOx (a-IGZO) channel thin-film transistors (TFTs) was investigated. a-IGZO film deposition with the addition of H2 gas was performed using a plasma-assisted reactive sputtering system to control the oxidation process during a-IGZO film formation by balancing the oxidation and reduction reactions. Optical emission spectroscopy measurements indicate the possibility for the oxidation reaction to be inhibited by a decrease in the density of oxygen atoms and the reduction effect of hydrogen during a-IGZO film deposition due to the addition of H2 gas. The characteristics of TFTs fabricated using a-IGZO films deposited with a plasma-enhanced magnetron sputtering deposition system were investigated. The results indicate the possibility of expanding the process window by controlling the balance between oxidation and reduction with the addition of H2 gas. TFTs with a-IGZO films that were deposited with the addition of H2 gas exhibited good performance with a field-effect mobility (μFE) of 15.3 cm2 V−1 s−1 and a subthreshold gate voltage swing (S) of 0.48 V decade−1.

Characterization of TiAlSiON coatings deposited by plasma enhanced magnetron sputtering: XRD, XPS, and DFT studies

The results of characterization of TiAlSiON hard coatings deposited on ferric-chromium AISI 430 stainless steel by plasma enhanced magnetron sputtering are presented. The coating with maximum hardness (of 43GPa) was obtained at the following optimal values of elemental concentrations: Si ~5at.%, Al ~15at.%, and Ti ~27at.%. The value of gaseous mixture (Ar–N2) pressure was of 0.13Pa and the value of partial pressure of oxygen (O2) was 1.3·10−3Pa. The X-ray diffraction (XRD) measurements showed the presence of Ti(Al)N. High-energy resolved XPS spectra of core levels revealed the formation of Ti–N, Ti–O–N, Si–N and Al–O–N bonds. Comparison of XPS valence band spectra with specially performed density functional theory calculations for disordered Ti0.5Al0.5N1−xOx (0≤x≤0.3) phases demonstrated that a Ti(Al)OxNy phase is formed on the surface of AISI430 steel upon the plasma enhanced magnetron sputtering, which can provide a good combination of high hardness and additional oxidation resistance of this material.

Microstructure and age hardening of C276 alloy coatings

C276 alloy layers were deposited on 4140 steel substrates by plasma enhanced magnetron sputtering. The as-deposited 12-μm-thick coatings exhibit a face centered cubic nanocrystalline structure with a grain size of 37–46nm and a uniform composition that replicates the C276 alloy deposition source. The as-deposited coating hardness H=6.2±0.3GPa is four times larger than the known bulk H=1.5–1.9GPa. This is attributed to the small grain size and associated Hall–Petch hardening. Annealing in air for 1h at 600°C, 700°C, and 800°C causes negligible changes in grain size but results in changes in microstructure and texture and a significant increase in H to 7.3–8.5GPa. Compositional maps by Auger electron and energy-dispersive spectroscopies as well as a secondary x-ray diffraction peak suggest that this increase is due to segregation and precipitation of Cr- and Mo-rich regions.

Mechanical properties, sliding wear and solid particle erosion behaviors of plasma enhanced magnetron sputtering CrSiCN coating systems

CrSiCN coating systems with different concentrations of Cr, Si, C, and N were investigated for their microstructure, mechanical properties (hardness H, elastic modulus E and indentation fracture toughness KIC) and tribological behaviors using SEM, nano-indentation, indentation, pin-on-disk wear test, and sand particle erosion test. The wear behaviors, such as specific wear rate and Archard wear coefficient, showed inverse relationships with H3/E2 ratio, confirming that the resistance to plastic deformation is the essential factor governing sliding wear behavior. High H3/E2 ratios also contributed to increased resistances to erosion at low impingement angles. However, at higher impingement angles (>60°), coatings with lower index of brittleness (B=2.656µm−1/2), higher critical load (P⁎=6.670N) for crack initiation and fracture surface energy (γf=0.123Jm−2) offered a higher erosion resistance. The indentation fracture toughness (KIC), hardness (H) and elastic modulus (E) are limited to interpret erosion behaviors in a comprehensive approach, suggesting that erosion is a complex process where multiple mechanical properties contribute to erosion performance.