scholarly journals Simulation of Neutron/Self-Emitted Gamma Attenuation and Effects of Silane Surface Treatment on Mechanical and Wear Resistance Properties of Sm2O3/UHMWPE Composites

Polymers ◽  
2021 ◽  
Vol 13 (19) ◽  
pp. 3390
Author(s):  
Donruedee Toyen ◽  
Yupadee Paopun ◽  
Dararat Changjan ◽  
Ekachai Wimolmala ◽  
Sithipong Mahathanabodee ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Wear Resistance ◽  
Surface Treatment ◽  
Gamma Rays ◽  
Surface Hardness ◽  
Thermal Neutrons ◽  
Simulation Code ◽  
Neutron Shielding ◽  
Wear Rates ◽  
Uhmwpe Composites

This work reports on the simulated neutron and self-emitted gamma attenuation of ultra-high-molecular-weight polyethylene (UHMWPE) composites containing varying Sm2O3 contents in the range 0–50 wt.%, using a simulation code, namely MCNP-PHITS. The neutron energy investigated was 0.025 eV (thermal neutrons), and the gamma energies were 0.334, 0.712, and 0.737 MeV. The results indicated that the abilities to attenuate thermal neutrons and gamma rays were noticeably enhanced with the addition of Sm2O3, as seen by the increases in µm and µ, and the decrease in HVL. By comparing the simulated neutron-shielding results from this work with those from a commercial 5%-borated PE, the recommended Sm2O3 content that attenuated thermal neutrons with equal efficiency to the commercial product was 11–13 wt.%. Furthermore, to practically improve surface compatibility between Sm2O3 and the UHMWPE matrix and, subsequently, the overall wear/mechanical properties of the composites, a silane coupling agent (KBE903) was used to treat the surfaces of Sm2O3 particles prior to the preparation of the Sm2O3/UHMWPE composites. The experimental results showed that the treatment of Sm2O3 particles with 5–10 pph KBE903 led to greater enhancements in the wear resistance and mechanical properties of the 25 wt.% Sm2O3/UHMWPE composites, evidenced by lower specific wear rates and lower coefficients of friction, as well as higher tensile strength, elongation at break, and surface hardness, compared to those without surface treatment and those treated with 20 pph KBE903. In conclusion, the overall results suggested that the addition of Sm2O3 in the UHMWPE composites enhanced abilities to attenuate not only thermal neutrons but also gamma rays emitted after the neutron absorption by Sm, while the silane surface treatment of Sm2O3, using KBE903, considerably improved the processability, wear resistance, and strength of the composites.

scholarly journals Properties of Journal Bearing Materials That Determine Their Wear Resistance on the Example of Aluminum-Based Alloys

Materials ◽  
2021 ◽  
Vol 14 (3) ◽  
pp. 535
Author(s):  
Alexander Mironov ◽  
Iosif Gershman ◽  
Eugeniy Gershman ◽  
Pavel Podrabinnik ◽  
Ekaterina Kuznetsova ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Wear Resistance ◽  
Journal Bearing ◽  
Tribological Behavior ◽  
Secondary Structures ◽  
Magnesium Content ◽  
Wear Rates ◽  
Relative Extension ◽  
Bearing Materials ◽  
Antifriction Alloys

Potential relations of tribological characteristics of aluminum antifriction alloys with their compositions and mechanical properties were investigated. In this regard, the properties of eight aluminum alloys containing tin from 5.4% to 11% doped with lead, copper, silicon, zinc, magnesium, and titanium were studied. Mechanical properties such as hardness, strength, relative extension, and impact strength were analyzed. Within the tribological tests seizure load and wear of material were evaluated and secondary structures were studied afterwards. The absence of a definitive correlation between tribological behavior and mechanical properties was shown. It was determined that doping tin over 6% is excessive. The seizure load of the alloys increases with the magnesium content. Secondary structures of the alloys with higher wear rates contain one order less magnesium and tin.

Wear Properties of Y-TZP Ceramics Dispersed with Second Phase Particles

2008 ◽  
Vol 368-372 ◽  
pp. 744-747
Author(s):  
Xiao Ping Liang ◽  
Shao Bo Xin ◽  
Xiao Hui Wang ◽  
Zheng Fang Yang
Keyword(s):  
Mechanical Properties ◽  
Wear Resistance ◽  
Mass Fraction ◽  
Normal Load ◽  
Roller Bearing ◽  
Second Phase ◽  
Wear Properties ◽  
Wear Rates ◽  
Second Phase Particles ◽  
Better Than

The wear properties of ADZ (alumina dispersed in Y-TZP) and MDZ (mullite dispersed in Y-TZP) were investigated by using a ring-on-block tribometer. The results showed that for Y-TZP ceramic, the addition of alumina phase (with 10-20% in mass fraction) leads to an improved wear resistance. With the increase of the normal load, the wear rates of ADZ ceramics increase. Under low and medium normal load (100N and 300N), the wear resistance is controlled by the hardness of ceramics, and under high normal load (500N) the fracture toughness is obviously contributed to the wear resistance of the ceramics. For MDZ ceramic, the wear resistance of 15MDZ (15wt% mullite dispersed in Y-TZP) is better than that of 20 MDZ (20wt% mullite) under the normal load from 100 N to 500 N. The mechanical properties of 15MDZ are worse than that of Y-TZP ceramic, but the wear resistance is enhanced due to the action of “needle roller bearing” of the fractured rod-like mullite particles.

ENHANCEMENT OF MECHANICAL PROPERTIES OF UHMWPE POLYMER BY NITROGEN ION IMPLANTATION

2020 ◽  
Vol 15 (4) ◽  
Author(s):  
Venkat Kishore N ◽  
Nagendra M ◽  
Venkateswara Rao T
Keyword(s):  
Mechanical Properties ◽  
Wear Resistance ◽  
Ion Implantation ◽  
Surface Treatment ◽  
Energy Levels ◽  
Testing Machine ◽  
Constant Load ◽  
Wear Testing ◽  
Treatment Technology ◽  
Nitrogen Ion

The use of ion implantation as a surface treatment technology has been conquered by its applications to prevent wear and oxidation in metal alloys, even though some early works already pointed out that ion implantation could also be effective as a surface treatment for other materials, including polymers. Further research has shown that low dose implantation of energetic light ions could be very effective for improving properties such as wear resistance and hardness in many different polymers. Cross linking of polymeric chains due to ionization energy provided by the stopping process is the main mechanism to explain the changes in mechanical properties. According to this model the lighter the ion is, the stronger is the effect. This thesis presents the results obtained by nitrogen implantation in ultra-high molecular weight polyethylene (UHMWPE). N+ ions were implanted at 80 keV, 100 keV and 120 keV energy levels which are maintained at a fluencies or dose of 5×1015 ions/cm2 . Wear resistance was measured using pin-on-disc wear testing machine at a constant load of 18 kg or 177N with a sliding speed of 2 m/s for about 1000m sliding distance. The results clearly show a lower weight and volume loses for samples implanted with nitrogen, in comparison to those implanted with untreated samples. Hence from the results of weight and volume loses of the treated or implanted samples with nitrogen ion, gives very good wear resistance than untreated samples.

Hardening Performance and Mechanism of Fluosilicate Surface Treatment Agent on Cement-Based Materials

2017 ◽  
Vol 898 ◽  
pp. 1996-2003
Author(s):  
Xiao Liu ◽  
Jia Nan Guan ◽  
Yun Sheng Zheng ◽  
Zi Ming Wang ◽  
He Qing Shen ◽  
...  
Keyword(s):  
Wear Resistance ◽  
Surface Treatment ◽  
Surface Hardness ◽  
Rapid Improvement ◽  
Soaking Time ◽  
Hardening Effect ◽  
Ecological Resources ◽  
Cement Based Materials ◽  
Treatment Agent ◽  
Silicate Surface

Based on the theory of ecological resources recycling, the effects of matrix quality, surface treatment method, soaking time, age after treatment and fluosilicate cation on hardening cement based materials were investigated by using the byproduct of phosphate fertilizer production namely fluosilicate as the surface treatment agent of cement-based materials and changing different surface treatments. The results showed that the permeation capacity of surface hardener solution , the wear resistance and surface hardness of cement-based materials were significantly improved by the treatments of surface sanding and oven drying. Both surface spraying and submerging methods can promptly increase the hardening effect by more than 20%, manifesting as the rapid improvement of wear resistance in 1 day and the maintenance of that in 7 days. The effective spraying amount and soaking time were 100g/m2-200g/m2 and 6 h, respectively. The fluosilicate surface hardener exhibited better hardening effect than the silicate surface hardener for those matrix materials with different quality, especially for the matrix materials with low compactness. The magnesium fluosilicate displayed the best hardening effect. Besides, the mechanism of fluosilicate and silicate surface hardeners were discussed and compared. The results show that the fluosilicate surface hardener produced crystals and colloids by reacting with cement hydrates to fill the void and improve the compactness, other than the silicate surface hardener which produced calcium silicates by reacting with cement hydrates. As a result, the hardness and wear resistance of cement-based materials are improved, but also the probability of a potential alkali-aggregate reaction is substantially reduced.

scholarly journals Effects of the Prefabricated Cu-Ti Film on the Microstructure and Mechanical Properties of the Multiphase Coating by Thermo Plasma Nitriding on C17200 Cu Alloy

Coatings ◽  
2019 ◽  
Vol 9 (11) ◽  
pp. 694
Author(s):  
Yandan Zhu ◽  
Mufu Yan ◽  
Quanli Zhang ◽  
Qiwen Wang ◽  
Hangyu Zhuo
Keyword(s):  
Mechanical Properties ◽  
Wear Resistance ◽  
Plasma Nitriding ◽  
Surface Hardness ◽  
Cross Sectional ◽  
Cu Alloy ◽  
Cu Substrates ◽  
Modified Surface ◽  
N Compounds ◽  
Ti Films

To improve the surface wear resistance, plasma nitriding of the prefabricated Cu-Ti films on the C17200 Cu alloy is performed to investigate the effects of the composition of the Cu-Ti films on the microstructure and the mechanical properties of the modified surface. The results firstly showed that obvious microstructure evolution appeared during the thermo-plasma nitriding process, where both the surface morphology of the composed phases and the cross-sectional profiles of the multiphase coatings varied for the three types of films. Small amounts of Ti-N compounds, Be3Ti2Cu, and different types of Cu-Ti intermetallics formed in the multiphase coating after plasma nitriding, which is dependent on the composition of the prefabricated Cu-Ti film. Correspondingly, the surface hardness and the wear resistance of the C17200 Cu substrates were obviously improved, with the obtained adhesive strength of the substrate reaching a satisfactory range.

scholarly journals Surface Modification of Ti-6Al-4V Alloy by Electrical Discharge Coating Process Using Partially Sintered Ti-Nb Electrode

Materials ◽  
2019 ◽  
Vol 12 (7) ◽  
pp. 1006 ◽  
Author(s):  
Chander Prakash ◽  
Sunpreet Singh ◽  
Catalin Pruncu ◽  
Vinod Mishra ◽  
Grzegorz Królczyk ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Wear Resistance ◽  
Electric Discharge ◽  
Composite Layer ◽  
Surface Hardness ◽  
Thick Layer ◽  
Dielectric Fluid ◽  
Machining Processes ◽  
Coated Surface ◽  
Coated Layer

In the present research, a composite layer of TiO2-TiC-NbO-NbC was coated on the Ti-64 alloy using two different methods (i.e., the electric discharge coating (EDC) and electric discharge machining processes) while the Nb powder were mixed in dielectric fluid. The effect produced on the machined surfaces by both processes was reported. The influence of Nb-concentration along with the EDC key parameters (Ip and Ton) on the coated surface integrity such as surface topography, micro-cracks, coating layer thickness, coating deposition, micro-hardness has been evaluated as well. It has been noticed that in the EDC process the high peak current and high Nb-powder concentration allow improvement in the material migration, and a crack-free thick layer (215 μm) on the workpiece surface is deposited. The presence of various oxides and carbides on the coated surface further enhanced the mechanical properties, especially, the wear resistance, corrosion resistance and bioactivity. The surface hardness of the coated layer is increased from 365 HV to 1465 HV. Furthermore, the coated layer reveals a higher adhesion strength (~118 N), which permits to enhance the wear resistance of the Ti-64 alloy. This proposed technology allows modification of the mechanical properties and surface characteristics according to an orthopedic implant’s requirements.

scholarly journals The Abrasion Behaviour of X40CrMoV5-1 Steel Under Various Surface Treatments

2020 ◽  
Vol 3 (1) ◽  
pp. 50-54
Author(s):  
László Tóth ◽  
Tünde Kovács ◽  
Zoltán Nyikes ◽  
Mhatre Umesh
Keyword(s):  
Heat Treatment ◽  
Wear Resistance ◽  
Surface Layer ◽  
Surface Treatment ◽  
Surface Hardness ◽  
Surface Treatments ◽  
Plasma Nitridation ◽  
Pvd Coating ◽  
Abrasion Wear ◽  
Wear Tests

AbstractFor evolving a surface layer on the X40CrMoV5-1 steel, a plasma-nitridation and PVD coating process was applied. In our experiments, the samples were heat-treated (high-temperature hardening, annealed three times) and surface treatments (plasma-nitridation, PVD coating by TiAlN, duplex surface treating by plasma nitridation and after that, PVD coating TiAlN). After the heat treatments, we performed hardness tests and surface abrasion wear tests. The abrasion wear resistance of the specimens was studied in order to understand the heat treatment effects on abrasion behaviour. It was observed that the heat treatment and surface treatment process greatly influence the tool steel surface hardness and abrasion resistance behaviour. By plasma-nitridation the surface hardness doubled compared to the quenched surface hardness while the PVD coated TiAlN surface layer hardness is more than five times that of the hardened one. There was no relevant difference between the PVD coated (TiAlN) surface hardness and the duplex surface-treated hardness. On the basis of the results of the comparative abrasive wear tests, it can be concluded that the duplex surface treatment resulted in the greatest wear resistance..

scholarly journals Effect of pack carburizing with chicken egg shell powder agent and vibrator quenching on the mechanical properties of AISI 9310 steel

2021 ◽  
Vol 6 (12 (114)) ◽  
Author(s):  
Sinarep Sinarep ◽  
Sujita Darmo
Keyword(s):  
Mechanical Properties ◽  
Wear Resistance ◽  
Cooling Rate ◽  
Surface Hardness ◽  
Specimen Surface ◽  
Hardness Number ◽  
Cooling Medium ◽  
Chicken Egg ◽  
Egg Shell ◽  
Shell Powder

The effects of vibrator quenching (QV) on the carbon content, microstructure, and mechanical properties (surface hardness number, wear resistance) in the pack carburizing of AISI 9310 steel were studied. The aim of this research is to increase the surface hardness and improve the wear resistance of AISI 9310 steel. The problem that often occurs in the quenching treatment after pack carburizing is that the thick cooling medium does not evenly wet the surface of the specimen, so that the cooling rate is not uniform, the impact is the distribution of the specimen surface hardness is not the same. Therefore, it is necessary to research the implementation of the vibrator in the quenching treatment.  The specimens were treated with pack carburizing at a temperature of 875 °C, soaking time for 3 hours. The carburizing agent consisted of chicken egg shell powder (CESP) and rice husk charcoal (RHC) with various weight ratios of 5 %:95 %, 15 %:85 %, and 30 %:70 %. Followed by quenching treatment using a 10 % cane molasses cooling medium and vibrator. Hardness testing was carried out using a Vickers microhardness tester, wear resistance test using the pin-on-disc method, and a scanning electron microscope (SEM-EDX) was used to observe changes in the microstructure and carbon elemental content on the specimen surface. The results showed that the application of VQ caused the formation of a small martensite microstructure while without VQ it was large martensite and a few of residual ferrite. The highest surface hardness number is 685 kg/mm2, the wear resistance is 0.32 cm/mg for pack carburizing, using carburizing agent 70 % RHC, 30 % CESP and VQ. VQ causes a more even distribution of the thick cane molasses cooling medium so that the cooling rate of the specimens is uniform.

Dry Sliding Behaviour of Peo (Plasma Electrolytic Oxidation) Treated AA 2618/20% Al2O3p Composite

2011 ◽  
Vol 678 ◽  
pp. 61-74 ◽  
Author(s):  
Lorella Ceschini ◽  
Carla Martini ◽  
Giuliano Sambogna ◽  
Fabrizio Tarterini
Keyword(s):  
Wear Resistance ◽  
Plasma Electrolytic Oxidation ◽  
Surface Hardness ◽  
Dry Sliding ◽  
Tribological Behaviour ◽  
Severe Wear ◽  
Wear Rates ◽  
Electrolytic Oxidation ◽  
Steel Particle ◽  
Plasma Electrolytic

The present study focuses on the influence of the PEO (Plasma Electrolytic Oxidation) treatment on the tribological behaviour of the AA2618/20 % vol. Al2O3p composite, dry sliding against induction hardened UNI C55 steel. Particle-reinforced Al based composites offer a higher wear resistance by comparison with the corresponding unreinforced alloys, however, the presence of critical loads and/or velocities which lead to transition towards severe wear regime, was often observed. In such conditions, the composite can show higher wear rates than those of unreinforced alloys. For this reason, surface modifications, such as PEO, might contribute to improve wear resistance. In this paper, topography, microstructure, phase constitution and surface hardness of the PEO-treated composite were investigated and its tribological behaviour was studied by dry sliding tests using a block-on-ring tribometer. The results were compared with those from the uncoated composite, demonstrating a very positive effect of the PEO treatment, which moved transitions from mild to severe wear towards more severe test conditions, in terms of both load and velocity.

scholarly journals Mechanical Properties of Multi-Walled Carbon Nanotube/Waterborne Polyurethane Conductive Coatings Prepared by Electrostatic Spraying

Polymers ◽  
2019 ◽  
Vol 11 (4) ◽  
pp. 714 ◽  
Author(s):  
Fangfang Wang ◽  
Lajun Feng ◽  
Man Lu
Keyword(s):  
Mechanical Properties ◽  
Electrical Conductivity ◽  
Wear Resistance ◽  
Carbon Nanotube ◽  
Surface Hardness ◽  
Waterborne Polyurethane ◽  
Conductive Coatings ◽  
Mwcnt Content ◽  
Electrostatic Spraying ◽  
Multi Walled Carbon Nanotube

Electrostatic spraying (ES) was used to prepare multi-walled carbon nanotube (MWCNT)/waterborne polyurethane (WPU) abrasion-proof, conductive coatings to improve the electrical conductivity and mechanical properties of WPU coatings. The dispersity of MWCNTs and the electrical conductivity, surface hardness, and wear resistance of the coating prepared by ES (ESC) were investigated. The ESC was further compared with coatings prepared by brushing (BrC). The results provide a theoretical basis for the preparation and application of conductive WPU coatings with excellent wear resistance. The dispersity of MWCNTs and the surface hardness and wear resistance of ESC were obviously better than those of BrC. With an increase in the MWCNT content, the surface hardness of both ESC and BrC went up. As the MWCNT content increased, the wear resistance of ESC first increased and then decreased, while the wear resistance of BrC decreased. It was evident that ESC with 0.3 wt% MWCNT was fully capable of conducting electricity, but BrC with 0.3 wt% MWCNT failed to conduct electricity. The best wear resistance was achieved for ESC with 0.3 wt% MWCNT. Its wear rate (1.18 × 10−10 cm3/mm N) and friction coefficient (0.28) were the lowest, which were 50.21% and 20.00% lower, respectively, than those of pure WPU ESC.

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