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Wear behavior of boronized GGG‐80 ductile cast iron were studied against WC‐Co ball for determining the effect of boronizing time and temperature.

Ball on disk arrangement was used for determination of tribological properties of boronized ductile cast iron depending on process time and temperature. Boronizing treatment was performed on GGG‐80 ductile cast iron using salt bath immersion boronizing technique at 850 and 950°C for 2‐8 h. Friction and wear tests were carried out at dry test conditions under 2, 5 and 10 N loads with 2.5 m/min sliding speed.

The result showed that the friction coefficient values ranged from 0.12 to 0.2 depending on the process parameters. The higher the treatment temperature and the longer the treatment time, the thicker the boride layer, the more the FeB phase and the higher the specific wear rate became. The specific wear rate of boronized ductile cast irons depending on process time, temperature and applied load against WC‐Co ball ranged from 1.25 × 10⁻⁵ to 42.45 × 10⁻⁵ mm³/Nm. Values of coefficient of boronized ductile cast irons increases with increase in load in the wear test and increase in boronizing time and temperature.

The study deals with only ductile cast irons and their tribological properties.

The results are very useful for practical applications and academic study. There is a little number of studies on the boronizing of cast irons. This study will be helpful for the researcher studied on boronizing of cast irons.

The properties of the tribological properties of ductile cast irons have not explained detail in the earlier study. There are new results in this study on the tribological properties of boronized ductile cast irons. Because of this, the paper is original.

The purpose of this paper is to study the tribological behavior of hardened, boronized and boro‐chromized AISI 52100 steel balls against boro‐chromized AISI 1040 steel disk under 2, 5 and 10 N loads at 0.1 and 0.3 m/s sliding speeds.

Boronizing treatment was realized at 1,000°C for 2 h in a slurry salt bath consisting of borax, boric acid and ferro‐silicon. Some of the boronized steels were chromized at 1,000°C for 2 h by pack method in the powder mixture consisting of ferro‐chromium, ammonium chloride and alumina. Similarly, AISI 1040 steel disk was boronized at 900°C for 4 h in the same bath and then chromized by pack method. Friction and wear tests were carried out using a ball‐on‐disk machine.

The results showed that the specific wear rate of hardened and boronized AISI 52100 steel balls decreased with increasing load and decreasing sliding speed. Untreated AISI 52100 steel balls showed much greater specific wear rate than the boronized and boro‐chromized AISI 52100 steel balls. Boronized steel balls exhibited the highest wear resistance. The specific wear rates of hardened, boronized and borochromized steel balls were between 9.6422 × 10⁻⁵ and 1.6714 × 10⁻⁴, 4.4079 × 10⁻⁶ and 3.2829 × 10⁻⁵, and 1.0135 × 10⁻⁵ and 3.0559 × 10⁻⁵ mm³ N⁻¹ m⁻¹, respectively. The lowest coefficient of friction was recorded on a boro‐chromized steel disk, tested against boronized steel ball at 0.3 m/s sliding speed and under low‐load value.

Tests have been made on the basis of atmospheric conditions. The study can be detailed using some lubricants on the wear test.

The research has shown that boronizing and boro‐chromizing treatments realized on steels have a good wear resistance in the open atmosphere. Boronizing treatment has been used for tribological applications for a long time. Boro‐chromizing treatment can be applied on steels, successfully.

Tribological properties of boro‐chromized steels are explained in the present study for the first time.

This paper aims to research the tribological features of AISI 1035 steel, boronized at various parameters.

The samples were boronized via box boronizing method. By using Ekabor 2 powders, boronizing was conducted at 840, 880, 920, 960 and 1,000°C for two, four and six hours. Wear resistance of boronized samples at determined parameters were analysed. Wear experiments were conducted under 40 N constant load at pin‐on‐disk experiment setup. Also, microstructures and microhardness values of boronized samples were analysed to determine the most suitable boronizing parameters against wearing.

As a result of this study, the following findings are reported: it was determined as the temperature increased, the thicker the boride layer obtained during the boronizing. In the case of longer boronizing time, the distinct columnar structure was clearer. Whenever applying higher temperature and longer boronizing time, wear decreased and hardness values increased. It was also determined that when boronizing was conducted at 900 and 1,000°C for at least four to six hours, better results were obtained. Furthermore, the increment in the boronizing temperature and longer duration caused an increase in hardness from the surface to inwards and thus a decrease in wear ratio.

In the present study, only 40 N is used for a wear load and that is the limitation of the research.

Boronizing of the parts using 900 and 1,000°C temperature and four to six hours time, the better results can be obtained. Wear resistance can be improved in the determined temperature interval for boronizing process. Therefore, the industrial firms can be gained huge economical profits.

The outcome of the study will be beneficial for the academicians and industrial firms working on wear process. The service life of the steel parts can be extended via boronizing of steels working on quarries.

This paper aims to clarify the relationship between the slurry erosion and one of the case hardening treatments, i.e. boronizing in this study, for AISI-5117 steel alloy. AISI-5117 steel alloy was used because of its variety applications in the field of submarine equipment. Most of the slurry erosion factors such as velocity, impact angle and mechanism of erosion were studied at different impact angles.

At first, the samples were prepared and subjected to the boronizing treatment in controlled atmosphere. By using a slurry erosion test-rig, all experiments for studying the slurry erosion factors were carried out. Moreover, the studied specimens were investigated via scanning electron microscope, optical microscope and X-ray diffraction to study the erosion mechanism in the different conditions.

It was expected that the boronization of the AISI-5117 steel would increase its slurry erosion resistance due to its positive impact on the surface hardness. However, the results observed show the opposite, where the boronization of AISI-5117 steel decreased its slurry erosion resistance as implied by the increase of the mass loss percentage at all impact angles.

This research, for the first time, exhibits the effect of boronizing treatment on the slurry erosion in different impact factors accompanied by the erosion mechanism at each impact angle.

This paper aims to investigate the effects of boriding on the structural, mechanical and tribological properties of CoCrW dental alloy manufactured by the method of selective laser melting.

In this study, CoCrW alloy samples that are used in dentistry were manufactured by the method of laser melting, and boriding treatment was made on the samples at 900°C and 1,000°C for 1, 4 and 8 h. The structural, mechanical and tribological effects of boriding on the samples were analyzed using X-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectroscopy, microhardness and an abrasion test device.

According to the results, the best outcomes in terms of abrasion strength and hardness were obtained in the sample that was subjected to boriding at 1,000°C for 4 h.

This study produced CoCrW alloys, which are fundamental biomaterials that are used in dentistry, by a different production method called selective laser melting and improved their surface characteristics by boriding.

This paper aims to improve the wear resistance of titanium alloy using a high-hardness boride layer, which was fabricated on Ti6Al4V by a high-temperature boronizing process.

The boride layers on Ti6Al4V were obtained at 1000°C for 5–15 h. Scanning electron microscopy, energy dispersive analysis and X-ray diffractometer were used to characterize the properties of the boride layer. The tribological performance of the boride layer at room and elevated temperatures was investigated.

The X-ray diffraction analysis showed that the boride layers were a dual-phase structure of TiB and TiB₂. When the boronizing time increased from 5 h to 15 h, the microhardness increased from 1192 HV_0.5 to 1619.8 HV_0.5. At 25°C and elevated temperatures, the friction coefficients of the boride layers were higher than that of Ti6Al4V. The wear track areas of T-5 at 200°C and 400°C were 2.5 × 10^–3 and 1.1 × 10^–3 mm², respectively, which were 6.1% and 2.6% of that of Ti6Al4V, indicating boride layer exhibited a significant wear resistance. The wear mechanisms of the boride layer transformed from slight peeling to oxidative wear and abrasive wear as the temperature was raised.

The findings provide an effective strategy for improving the wear resistance of Ti6Al4V and have important implications for the application of titanium alloy in a high-temperature field.

The purpose of this paper is to produce cobalt (Co)-based thin films by metalorganic chemical vapor deposition (CVD) technique and then to evaluate structural and mechanical integrity.

Co-based thin films were produced by metalorganic CVD technique. Boronizing, carburization and nitridation of the produced Co thin films were accomplished through a post-treatment stage of thermal diffusion into as-deposited Co thin films, in order to produce cobalt boride (Co₂B), cobalt carbide and cobalt nitride thin films in the surface layer of Co. The surface topography and the crystal structure of the produced thin films were evaluated through scanning electron microscopy and X-ray diffraction, respectively. The mechanical integrity of the produced thin films was evaluated through nanoindentation technique.

The obtained results indicate that Co₂B thin film exhibits the highest nanomechanical properties (i.e. H and E), while Co thin film has enhanced plasticity. The cobalt oxide thin film exhibits higher resistance to wear in comparison to the cobalt thin film, a fact that is confirmed by the nanoscratch analysis showing lower coefficient of friction for the oxide.

This work is original.

Erosion and abrasion are the prominent wear mechanisms reducing the lifetime of machine components. Both wear mechanisms are playing a role meanwhile, generating a synergy, leading to a material removal on the target. The purpose of study is to create a mathematical expression for erosive abrasive wear.

Many factors such as environmental cases and material character have an influence in erosive abrasive wear. In the work, changes in abrasive size and material hardness have been analyzed. As an abrasive particle, quartz sand has been used. All tests have been done in 20 wt.% slurry. Heat treatment has been applied to different steel specimens (steel grades C15, St 37 and Ck45) to change hardness value, which ranged from 185 to 880 Vickers hardness number.

After the four-hour test, it is determined that by an increase in abrasive size and decrease in material hardness, wear rate increases. Worn surfaces of the targets have been examined to figure out the wear mechanisms at different conditions under scanning electron microscopy. The results indicate that by an increase in material hardness, the number and diameter of micro-craters on the worn surfaces decrease. The diameters of micro-craters have been about 3–8 µm in hard materials and about 120–140 µm in soft materials.

It is determined that by an increase in abrasive size and decrease in material hardness, wear rate increases. The results indicate that by an increase in material hardness, the number and diameter of micro-craters on the worn surfaces decrease.

The study enables to indicate the dominant factor in worn steel used in mechanical components.

After analyzing the test results, a novel mathematical expression, considering both abrasive size and material hardness, has been developed.

Plasma transferred arc (PTA) coating is a novel method for surface-coating applications. In this method, the substrate is melted using a plasma arc, and surfacing agents such as carbides are introduced to the melt pool. The purpose of this study is to investigate the effect of boron carbide (B₄C) in nickel-based coating on AISI 4140 steel.

Samples were tested on a ball-on-disc wear device, and the microstructure, as well as wear properties, were investigated using SEM and XRD.

The effect of B₄C addition was shown to be linear, with a p-value of 0.0248, indicating strong evidence. The reason for this increase was found to be the increase in third-body generation resulting from hard phases that form couples with the soft base material, nickel. It was concluded that using 6 per cent B₄C was the optimal solution.

In the literature, the effect of neither low temperature on a nickel coating with B₄C nor B₄C as a single surfacing agent in a nickel base has been investigated.