Reciprocating Wear Behavior Research Articles

Reciprocating wear behaviour of TiC-stainless steel cermets

TiC based cermets have been prepared with three different grades of stainless steel binder (304L, 316L and 410L). The cermets were densified by vacuum melt infiltration, at 1500°C, which allows the steel binder content to be readily varied from 5 to 30vol%. The cermets were assessed for their hardness and indentation fracture resistance using Vickers testing. The reciprocating wear response was evaluated using a ball on flat geometry, with a WC-Co counter face sphere. It was shown that the coefficient of friction increases with increasing steel binder content, and also with increasing load and wear time. Similarly, the specific wear rate increases with both steel binder content and applied load, but was largely independent of the steel grade used.

The effects of TiC grain size and steel binder content on the reciprocating wear behaviour of TiC-316L stainless steel cermets

TiC-based cermets are heavily utilised in applications demanding good resistance to both wear and corrosion. In the current work, TiC-stainless steel (grade 316L) cermets have been developed, with the TiC grain size varied through heat-treatment, for steel binder contents between 10 and 30vol%. Microstructural analysis showed mean TiC grain sizes of ~4 and 10μm, respectively, for fine- and coarse-grained cermets, with the grain size nominally consistent as a function of binder content. Sliding wear resistance was assessed in a reciprocating motion, using a WC–Co counter face sphere paired against the TiC cermets. Overall, the fine-grained cermets exhibit better wear resistance and hardness. The specific wear rate was seen to increase with applied load and/or binder content, for both fine- and coarse-grained materials. SEM and FIB microscopy were used to assess the microstructural changes occurring during wear. A two- to three-body abrasive wear transition was apparent, together with the formation of a surface tribolayer, which highlights a further evolution to an adhesive wear mechanism. The tribolayer showed incorporation of a high concentration of O, which increased with the applied load, together with a predominance of the binder constituents.

Influence of the heat treatment path on the martensite phase and dry reciprocating wear behavior of dual-phase steels

In order to explore the tribological potential of dual-phase (DP) steel as a wear-resistant material, the wear and friction characteristics of this steel, which consists of soft ferrite and hard martensite phases, was investigated. A low-carbon (0.11% C) steel was subjected to three different annealing heat treatments in order to develop different martensite percentages and morphologies, i.e., island types, a bulky and interconnected network, and fibrous (fine, needle-like), respectively. Dry reciprocating wear tests were performed under atmospheric conditions of 25 °C using a pin-on-disk apparatus at different loading conditions ranging from 18.9 N to 43.6 N and at a constant sliding velocity of 0.22 m/s. The lowest wear rate was obtained for the DP steel with an ~87% volume fraction (V F ) of martensite, reflecting the effect of hardness imparted by the increasing amount of martensite, which is a hard and load-bearing phase, while the highest wear rate was for the DP steel with a ~36% martensite V F . The analysis of the surface, subsurface and wear debris of specimens using a scanning electron microscope (SEM) showed that the wear mechanism was mainly mild oxidative wear. The friction and wear rate of the steels are explained with respect to the microstructure and the wear mechanism.

Reciprocating Wear Behavior of Al Alloys: Effect of Porosity and Normal Load

Aluminum alloys are attractive for critical applications such as pistons, clutch housings and liners in automotive industry for their high strength to weight ratio, high corrosion resistance and good heat conductivity. These alloys can be fabricated using casting and powder metallurgy techniques in which porosity is a common feature. The presences of pores adversely affect the mechanical properties and wear resistance of these components. Not only the total area percentage of porosity influences the degradation in properties but also size, shape and interconnectivity of pores play an important role. In this study, aluminum alloys were produced using powder metallurgy technique. The amount of porosity was varied by varying compaction pressure and amount of wax added before compaction. Reciprocating wear tests (ball-on-flat configuration) were performed against AISI 52100 bearing steel ball under both low (1.5- 5N) and high (6-20N) loads. Scanning electron microscopy was employed in order to identify possible wear mechanisms. Both detrimental and beneficial effects of porosity under different loading conditions were observed. An attempt has been made to develop a relationship between pore size and distribution and wear behavior of aluminum alloys.

Reciprocating wear behavior of mild steel carburized using Na2CO3–NaCl

The surface of the mild steel carburized using Na2CO3–NaCl was dominated by retained austenite. Towards the core, the amount of austenite reduced while the amount of martensite increased. Increasing the duration of the carburization resulted in higher peak hardness and case depth. It also increased the amount of cementite in the grain boundaries and the austenite grains size, rendering the steel more susceptible to cracking. The superior wear resistance of the martensite, as compared to the austenite, could be attributed to its high cracking and adhesive wear resistance owing to its high hardness and tendency to form oxides. The friction was governed by the wear mechanism and the type of microstructure at the worn scar sliding on the carbide ball.

Reciprocating wear behavior of WC–10Ni3Al cermet in contact with Ti6Al4V

Cermets based cutting tools remain widely used in machining processes for their wear resistance. WC–Ni3Al cermets are potential replacements of WC–Co cermets in titanium machining due to their superior mechanical and chemical properties, especially at elevated temperature. In present study the reciprocating sliding wear behavior of WC–10Ni3Al was investigated using a ball-on-flat tester, with the Ti6Al4V sphere as the counter-face material. Meanwhile, the diffusion test between WC–10Ni3Al cermet and Ti6Al4V was conducted for further study of the reciprocating sliding wear mechanisms of WC–10Ni3Al. The WC–8Co was utilized as the reference material. The experimental results show that WC–10Ni3Al has a higher wear resistance than WC–8Co, for all the examined contact loads. Adhesive wear is the main wear mechanism for both WC–10Ni3Al and WC–8Co. The severer adhesion and element diffusion leads to the serious wear of WC–8Co surface, while WC–10Ni3Al can maintain the lower wear due to its low chemical affinity and element diffusion with Ti6Al4V, even under the high contact load.

Reciprocating wear behavior of 7075Al/SiC in comparison with 6061Al/Al2O3 composites

In the present study, the reciprocating wear behavior of 7075Al/SiC composites and 6061Al/Al2O3 composites that are prepared through liquid metallurgy route is analyzed to find out the effects of weight percentage of reinforcement and load at the fixed number of strokes on a reciprocating wear testing machine. The Metal Matrix Composite (MMC) pins are prepared with different weight percentages (10, 15 and 20%) of SiC and Al2O3 particles with size of 36μm. Hardness of these composites increases with increase in wt.% of reinforcement. However, the impact strength decreases with increase in reinforcement content. The experimental result shows that the volume loss of MMC specimens is less than that of the matrix alloy. However, the volume loss is greater in 6061Al/Al2O3 composites when compared to 7075Al/SiC composites. The temperature rise near the contact surface of the MMC specimens increases with increase in wt.% of reinforcement and applied load. The coefficient of friction decreases with increase in load in both cases.

Effect of the amount of SiC, number of strokes, and applied load on the reciprocating wear behavior of Al-SiC composites

Abstract The wear behavior of Al/SiC composites prepared by stir casting technique is investigated to find out the effects of the weight percentage of SiC, load, and the number of strokes on a shaper machine. Metal matrix composite (MMC) pins are prepared with different weight percentages of SiC (10%, 15%, and 20%). The tests are carried out with different load conditions (25, 50 and 75 N) and different number of strokes (420,780 and 1605 strokes). Wear surfaces of tested samples are examined in scanning electron microscope (SEM). Hardness and impact tests are also carried out on the MMC samples. The experimental results show that the hardness of composites increases with an increase in SiC particle, and the impact strength decreases with increase in SiC content. The volume loss of MMC specimens are less than that of the matrix alloy. Moreover, the temperature rise near the contact surface of the MMC specimens increases with increase in wt% of SiC, load, and number of strokes. The coefficient of friction decreases with increase in load and the number of strokes.

Reciprocating Wear Behavior of Ductile Cast Iron Modified by Pulse Plasma Technology

Wear resistance of ductile iron can be improved through di erent surface engineering techniques, each having some limitations and drawbacks. Recently, a new method called pulse plasma technology has been introduced, which through local reinforcement with inserts improves wear resistance of ductile iron without compromising other properties. This paper deals with the improvement of the wear resistance of ductile iron surface modi ed by pulse plasma technology using a tungsten electrode. The surfaces of the samples were treated by C3H8, air, and oxygen gases. The surface morphology and the phase structure in the near surface region of original and treated samples were analyzed with optic microscope, scanning electron microscope and energy-dispersive spectroscopy. The surface properties were evaluated by measuring the microhardness, wear properties and friction coe cient, as well as the elemental depth pro les and chemical composition of the modi ed layer. It was found that the microhardness of the treated samples was much higher. The tribological resistances were also signi cantly improved, as con rmed by the reduced friction coe cient and wear track width. This improvement can be attributed to the di usion of tungsten on the surface layer.

The reciprocating wear behaviour of TiC–304L stainless steel composites prepared by melt infiltration

TiC-based ceramic–metal composites, or cermets, are widely used in applications requiring wear and corrosion resistance. In the present work, a family of novel TiC–stainless steel (grade 304L) cermets has been developed using vacuum melt infiltration (1500°C/1h), with steel binder contents varied from 5 to 30vol%. Microstructural analysis showed a homogenous distribution of TiC within the steel binder, with mean TiC grain sizes of ∼6μm. Increasing the steel content resulted in an increase in the indentation fracture resistance and a decrease in the hardness. The reciprocating wear resistance of the cermets was assessed using a ball-on-flat geometry, using a WC–Co sphere dry sliding on the polished cermet surface. It was shown that there is an increase in the specific wear rate with both increasing load and binder content. Similarly, a higher coefficient of friction was observed with higher steel binder contents. The morphology of the worn surface was investigated using scanning electron microscopy, and associated energy dispersive X-ray spectroscopy, to more fully understand the operative wear mechanisms. Evidence of a transition from two- to three-body abrasive wear was observed, together with the formation of a tribolayer, indicating that adhesive wear was also occurring.

Reciprocating Wear Behavior of Ni-Co Alloys Produced by Pulse Current Electrodeposition

In the present work, Ni Co alloy coatings were prepared from a modi ed Watt type electrolyte by direct current. For this purpose, current density was investigated for optimization to obtain high quality coatings on the steel copper substrates. The depositions were controlled to obtain speci c thickness (between 50 and 200 μm). The characterization of the coatings was investigated by scanning electron microscopy and X-ray di raction facilities. The hardness of the resultant coatings was also measured. The e ects of the current density on the tribological properties of Ni Co coatings were investigated. The results showed that although increasing current density showed increasing coating thickness, the wear resistance of the Ni Co alloys was decreased due to Co depletion in the deposited layer.

Self-Lubricating Cold-Sprayed Coatings Utilizing Microscale Nickel-Encapsulated Hexagonal Boron Nitride

It is often beneficial to modify surfaces to gain desirable properties such as improved wear and friction resistance. Self-lubricating coatings can improve the performance of contacting surfaces and extend component lifetimes by reducing the coefficient of friction and/or improving resistance to specific wear modes. With these goals in mind, self-lubricating coatings of hexagonal boron nitride (hBN) particles in a deposited nickel matrix were investigated and optimized for friction and wear. These self-lubricating coatings were created via high-velocity particle consolidation or cold spray using micrometer-sized hBN powder encapsulated by nickel and nickel phosphorous alloys. Relatively thick nickel encapsulation via electrolesss Ni plating was required to aid in coating bonding/formation by “tricking” the hBN into acting as monolithic Ni during deposition. Once deposited on aluminum substrates, the coatings were analyzed and found to exhibit enhanced mechanical and tribological properties such as high bond strength and microhardness, a relatively low coefficient of friction, and improved reciprocating wear behavior relative to pure cold-sprayed Ni coatings. Furthermore, the encapsulation process was found to be both scalable and amenable to relatively small hBN particles.

Study on the Effect of Process Parameters on Reciprocating Wear Behavior of Components Produced by Selective Laser Sintering (SLS)

This work presents the results of a study carried out to determine the reciprocating wear behavior and its effect on the process parameters of components manufactured by selective laser sintering (SLS). A standard procedure and specimen had been used in the present study to find the wear behavior. Using Taguchi’s experimental technique, an orthogonal array of modified L9 had been developed. Reciprocating wear testing was carried out and analysis of variance (ANOVA) technique was used to investigate the effect of process parameters and to identify the main process parameter that influences the properties of wear behavior on the SLS components. It has been found that laser power had more influence on wear as compared to other selected process parameters. Micro-structural analysis was also carried out using scanning electron microscope on the wear testing sample.

The reciprocating wear behaviour of TiC–Ni3Al cermets

TiC-based cermets have become more popular as a replacement to traditional WC–Co ‘hardmetals’ due to their superior mechanical properties at elevated temperatures, improved corrosion resistance and significantly lower density. The current study assesses the reciprocating wear response of TiC–Ni3Al cermets fabricated by melt infiltration, with Ni3Al binder contents ranging from 20 to 40vol.%. Wear testing was performed using a ball-on-flat geometry, with a WC–Co sphere used as the counter-face material. It is demonstrated that the cermets are affected by similar wear mechanisms for each of the binder contents, but displayed the lowest wear when prepared with 30vol.% Ni3Al. Additionally, the 40vol.% samples displayed a clear transitional behaviour, with an improved wear resistance comparable to the 30vol.% samples at low applied loads, but a degraded wear response comparable to the 20vol.% samples at high applied loads.

The effect of electromagnetic stirring and cerium addition on dry sliding reciprocating wear of hypereutectic aluminium–silicon alloy

Influences of electromagnetic stirring (EMS) and rare earth (RE) CeO2 addition on reciprocating wear behaviour of hypereutectic Al–Si alloys have been presented in this article. Reciprocating wear tests were carried out at different contact loads (from 15 to 90 N) and speeds (from 0.2 to 1.0 m/s) using pin-on-plate configuration for a constant sliding distance of 500 m. It was observed that EMS and RE (CeO2) addition refined the microstructure and improved the hardness. EMS reduced the wear rates of hypereutectic Al–Si alloy irrespective of applied load and sliding velocity. Transition from mild to severe wear was observed in as-cast alloy at 90 N normal load (constant sliding velocity = 0.4 m/s). Scanning electron microscopy of worn surfaces and wear debris was carried out to study the wear mechanism of material removal under different sliding conditions.

Reciprocating Wear Behaviour of Two Dimensionally Reinforced Carbon-Phenolic and Carbon-Epoxy Composites

A comparative study has been carried out on performance of two-dimensionally reinforced carbon/phenolic (C/P) and carbon/epoxy (C/E) composites, subjected to low amplitude reciprocating wear at different temperatures. The C/P composite has shown greater wear rate than the C/E composite, with the difference being modest at room temperature, and larger at 250 °C. The values of coefficient of friction, surface roughness, and depths of craters on worn surfaces have been measured, which along with surface morphologies examined by scanning electron microscope have been correlated to both amount of weight loss and mechanisms of damage by wear.

A Fractional Factorial Design Study of Reciprocating Wear Behavior of Al-Si-SiCp Composites at Lubricated Contacts

The lubricated reciprocating wear behavior of two composites A319/15%SiCp and A390/15%SiCp produced by the liquid metallurgy route was investigated by means of an indigenously developed reciprocating friction wear test rig using a fractional factorial-design approach. The main purpose was to study the influence of wear and friction test parameters such as applied load, sliding distance, reciprocating velocity, counter surface temperature and silicon content in composites, as well as their interactions on the wear and friction characteristics of these composites. Two output responses (wear loss and coefficient of friction) were measured. The input parameter levels were fixed through pilot experiment conducted in the newly developed reciprocating friction and wear test rig. The counter surface material used for the wear study was cast iron having Vickers hardness of 244 HVN. It had been demonstrated through established equations that A390/15%SiCp composite is subjected to low wear compared to the A319/15%SiCp composite. The experimental results indicate that the proposed mathematical models suggested could adequately describe the performance indicators within the limits of the factors that are being investigated. The applied load, sliding distance, reciprocating velocity, counter surface temperature, and silicon content in composite are the five important factors controlling the friction and wear characteristics of the composite in lubricated condition. Moreover, the two factor interactions have a strong effect on the wear of composites. The results give a comprehensive insight into the wear of the composites.

Effect of Experimental Parameters on Reciprocating Wear Behavior of Al-Si-SiCp Composites under Dry Condition

In this paper the nonlinear dry reciprocating wear behavior of three composites A319/15%SiCp A336/15%SiCp and A390/15%SiCp subjected to high temperature were reported. Composites were produced through liquid metal metallurgy route. Five controllable input parameters selected for the wear study were applied load, reciprocating velocity, sliding distance, counter surface temperature and silicon content in composites. Two output responses wear and coefficient of friction were measured. The input parameter levels were fixed through pilot experiment conducted in the indigenously developed reciprocating friction and wear test rig. The counter surface material used for the wear study was cast iron having Vickers hardness of 244 HVN. Wear study under dry condition was carried out through response surface methodology by considering five input parameters as variables and two output parameters as responses. It had been demonstrated through established equations that the nonlinearity is more pronounced with the increase in applied load and reciprocating velocity. Also it was found that high percentage silicon content composite exhibited a low wear compared to the low percentage silicon content composite. Moreover, the wear increased with increasing applied load, sliding distance and counter surface temperature and it decreased with silicon content in composites and square of reciprocating velocity.

Wear characterization of Ti–6Al–4V under fretting–reciprocating sliding conditions

Wear affects life, vibrational characteristics, and dimensional stability of the components that slide against each other in small oscillatory movements. This study investigated the fretting–reciprocating wear behavior of a titanium alloy under cylinder-on-flat contact configuration (both Ti–6Al–4V) with bulk cyclic loading. Four series of tests were conducted to characterize the effects of sliding and loading parameters on the wear behavior. These were the relative slip, contact load, number of cycles, and bulk cyclic stress. The reciprocating wear produced “U-” and “W-”shaped (scar with multiple valleys) scars on the specimen as well as on the pad. Optical and scanning electron microscopy of the wear scars was conducted to study the wear mechanism(s). MATLAB-based computer programs were developed to determine the wear volume using the three-dimensional profilometry data, the product of contact load ( P) and relative slip ( δ), and the energy dissipated ( E d) per fretting cycle. Analysis of the experimental data showed that the cyclic stress increased the relative slip. The ratio of shear force to contact load ( Q/ P) increased with number of fretting cycles. The wear volume was proportional to the cumulative products of Σ Pδ n and the dissipated energy Σ E d. The microscopy of W-shaped scars showed that the valleys were covered by abrasive grooves, whiles the peaks showed signs of adhesive wear, thus suggesting that the wear was caused by both the adhesion and abrasion processes.

Effect of copper addition on the temperature dependent reciprocating wear behaviour of CrN coatings

CrN–Cu nanocomposite coating was produced by hybrid method using both cathodic arc and magnetron sputtering PVD technique. Reciprocating wear behaviour of the coatings was investigated at room temperature, 50, 100 and 150 °C. The tribological behavior of copper doped CrN is compared with undoped coatings. The differences observed in the wear behavior are related to the character of the wear debris formed at the tribocontact regions which are characterized with micro-Raman spectroscopy. The results of this study showed that it is possible to design CrN coatings showing temperature independent wear behavior by introducing oxygen into their structure.