Effect of Temperature on Tribological Performances of Ion Nitrocarburized Layer of 42MnCr52 Steel

2013 ◽  
Vol 750-752 ◽  
pp. 389-392
Author(s):  
Chun Hua Hu ◽  
Feng Jun Qi ◽  
Meng Liang Lu ◽  
Guo Ning Wang ◽  
Qian Liu ◽  
...  
Keyword(s):  
Wear Resistance ◽  
Friction Factor ◽  
Wear Scar ◽  
Friction Reduction ◽  
Effect Of Temperature ◽  
Different Temperatures ◽  
Higher Temperature ◽  
Plain Surface ◽  
Nitrocarburized Layer ◽  
Scar Width

The paper studied that effect of temperature on tribological performances of ion nitrocarburized layer of 42MnCr52 steel under CD15W-40 oil lubricating. It is found that the ion nitrocarburized layer has more excellent friction reduction and wear resistance performances than the plain surface under different temperatures, especially under the higher temperature 150°C, the friction factor and wear scar width of ion nitrocarburized layer is 36% and 77% less than that of the plain surface respectively, which indicates that ion nitrocarburized layer can play more excellent friction reduction, wear resistance and scuffing resistance performances under the relative higher temperature.

Study on Tribological Performances of n-Na2B4O7/ion Nitrocarburized Duplex Layer at Different Temperatures

2014 ◽  
Vol 1004-1005 ◽  
pp. 1305-1310
Author(s):  
Chun Hua Hu ◽  
Zhi Chang Deng ◽  
Bao Shan Bian ◽  
Long Li ◽  
Hai Tao Wang
Keyword(s):  
Wear Resistance ◽  
Friction Factor ◽  
Chemical Reaction ◽  
Friction Surface ◽  
Intermediate Frequency ◽  
Friction Reduction ◽  
Solid Lubrication ◽  
Volume Loss ◽  
Different Temperatures ◽  
Higher Temperature

The paper studied the tribological performances of n-Na2B4O7/ion nitrocarburized duplex layer at different temperatures. It is found that the n-Na2B4O7/ion nitrocarburized duplex layer has more excellent friction reduction and wear resistance performances than the intermediate frequency quenched surface under CD15W-40 oil lubricating at different temperatures, especially at the higher temperature 100°C, the friction factor and volume loss of the duplex layer is 63% and 96% less than that of the intermediate frequency quenched surface respectively, which indicates that n-Na2B4O7/ion nitrocarburized duplex layer can play more excellent friction reduction, wear resistance and scuffing resistance performances at the relative higher temperature. This because that the chemical reaction films including oxide, BN and so on formed on the friction surface play the solid lubrication function, and the n-Na2B4O7 particles on the friction surface play the "Micron nanobearing" function.

Effect of n-Na2B4O7 Additive on Tribological Performances of Ion Nitrocarburized Layer

2015 ◽  
Vol 1120-1121 ◽  
pp. 254-259
Author(s):  
Chun Hua Hu ◽  
Hai Jiang ◽  
Yun Feng Du ◽  
Hai Peng Wang ◽  
Zhi Chang Deng
Keyword(s):  
Wear Resistance ◽  
Friction Surface ◽  
Sliding Friction ◽  
Synergetic Effect ◽  
Rolling Friction ◽  
Friction Reduction ◽  
Solid Lubrication ◽  
Higher Temperature ◽  
Different Content ◽  
Nitrocarburized Layer

The paper studied the effect of n-Na2B4O7additives of different content on tribological performances of the ion nitrocarburized layer. It is found that 7% n-Na2B4O7additive can improve greatly the friction reduction and wear resistance of the ion nitrocarburized layer under different conditions. This because that synergetic effect of friction reduction and wear resistance is produced between n-Na2B4O7additive and ion nitrocarburized layer under higher temperature, frequence and load, and the chemical reaction films including oxide, nitride, BN, and sulphide and so on formed on the friction surface play the solid lubrication function, and the n-Na2B4O7particles on the friction surface play the "Micron nanobearing" function, translating the sliding friction into the rolling friction, which can make the ion nitrocarburized layer possess the excellent tribological performances.

Effect of n-LaB4O7 Additive on Tribological Behaviors of Ion Nitrocarburized Layer at Higher Temperature

2015 ◽  
Vol 1120-1121 ◽  
pp. 249-253
Author(s):  
Chun Hua Hu ◽  
Jun Xue ◽  
Yun Kai Wang ◽  
Ya Zhi Li ◽  
Zhi Chang Deng
Keyword(s):  
Wear Resistance ◽  
Friction Surface ◽  
Synergetic Effect ◽  
Friction Reduction ◽  
Solid Lubrication ◽  
Tribological Behaviors ◽  
Temperature Load ◽  
Higher Temperature ◽  
Nitrocarburized Layer

The paper studied the effect of n-LaB4O7additives of different contents on tribological behaviors of the ion nitrocarburized layer at higher temperature. It is found that 7% n-LaB4O7additives can improve obviously the tribological performances of the ion nitrocarburized layer. This because that synergetic effect of friction reduction and wear resistance is produced between the n-LaB4O7additives and ion nitrocarburized layer under higher temperature, load and frequence, and the solid lubrication films including oxide, nitride and sulphate and so on are formed on the friction surface to separate the contact between the metal sufaces, and furthermore the n-LaB4O7particles on the friction surface play the "Micron nanobearing" function, which make the ion nitrocarburized layer have the more excellent tribological performances.

Study on Friction Reduction and Wear Resistance Process and Composition of FeS Solid Lubrication Duplex Layer

2012 ◽  
Vol 502 ◽  
pp. 60-66 ◽  
Author(s):  
Chun Hua Hu ◽  
Jia Ping Zou ◽  
Jiu Juan Qian ◽  
Ding Yun Jin ◽  
Xiao Feng Sun
Keyword(s):  
Wear Resistance ◽  
Surface Layer ◽  
Diffusion Layer ◽  
Steel Surface ◽  
Friction Reduction ◽  
Solid Lubrication ◽  
Wear Volume ◽  
Load Bearing Capacity ◽  
Lubricating Property ◽  
Plain Surface

The composition of FeS solid lubrication duplex layer on 45 steel surface was studied by using SEM, EDS, AES and XPS. The results show that the sulphurized surface layer of FeS solid lubrication duplex is composed of the sulphide aggradation layer deposited on the nitrocarburized sub-surface layer and the sulphide diffusion layer formed by some S element infiltrating the nitrocarburized surface. The sulphide aggradation layer is mainly composed of FeS and FeS2, the key composition of the sulphide diffusion layer is FeS, and Fe(2/3/4)N is the key composition of the nitrocarburized sub-surface layer. The result of friction reduction and wear resistance test combined with the composition of FeS solid lubrication duplex layer explains that the friction coefficient and wear volume of the duplex layer are lower than those of the plain surface, which attribute to the relatively softer sulphurized surface layer provided self-lubricating property while the harder nitrocarburized sub-surface layer provided sufficient load bearing capacity in view of resistance to plastic deformation, so that spallation failure of the sulphurized surface layer can be effectively avoided, and they exert excellent friction reduction and wear resistance functions in different moments during rubbing process respectively.

Tribological Performances of Active Screen Ion Sulphurized Layer under Epinoc Grease Lubricating

2012 ◽  
Vol 472-475 ◽  
pp. 2854-2858
Author(s):  
Chun Hua Hu ◽  
Feng Jiang ◽  
Zhen Duo Zheng ◽  
Jun Cao ◽  
Yu Lin Qiao ◽  
...  
Keyword(s):  
Wear Resistance ◽  
Cast Iron ◽  
Friction Reduction ◽  
Wear Volume ◽  
Grease Lubrication ◽  
Lubrication Condition ◽  
Plain Surface ◽  
Alloy Cast Iron ◽  
Alloy Cast ◽  
Active Screen

The active screen ion sulphurized layer was prepared on the surface of CrMoCu alloy cast iron by using active screen ion sulphurizing technology. Its key composition is FeS. Under epinoc grease lubrication condition, the friction factor and the wear volume of the active screen ion sulphurized layer is 24% and 40% lower than that of the plain surface and close to that of the sulphurized layer, respectively. The active screen ion sulphurized layer has excellent self-lubrication property, and its loose and porous structure tending to store the grease, which make it possess excellent friction reduction and wear resistance performances.

scholarly journals Defibration mechanisms and energy consumption in the grinding zone – a lab scale equipment and method to evaluate groundwood pulping tools

2020 ◽  
Vol 35 (1) ◽  
pp. 25-33 ◽  
Author(s):  
Magnus Heldin ◽  
Urban Wiklund
Keyword(s):  
Energy Consumption ◽  
Separation Process ◽  
Energy Requirements ◽  
Effect Of Temperature ◽  
Robust Testing ◽  
Different Temperatures ◽  
Grinding Stones ◽  
Grinding Tool ◽  
Higher Temperature ◽  
The Cost

AbstractGroundwood pulping is a process that employs large machines, making them difficult to use in research. Lab scale grinders exist, but even though they are smaller, the sizes of the grinding stones or segments make them cumbersome to exchange and tailor. This study presents a method and an apparatus for investigating the detailed mechanisms and the energy requirements behind the fibre separation process. A well-defined grinding tool was used at three different temperatures to demonstrate that the equipment can differentiate levels of energy consumption and defibration rates, confirming the well-known fact that a higher temperature facilitates defibration. It is also shown how the equipment can be used to study the influence of grinding parameters, exemplified by the effect of temperature on the way fibres are separated and the character of the produced fibres. A key feature of the equipment is the use and evaluation of small grinding surfaces, more readily designed, produced, evaluated and studied. This reduces both the cost and time necessary for testing and evaluating. At the same time, a technique to produce well defined grinding surfaces was employed, which is necessary for repeatability and robust testing, not achievable with traditional grinding stones.

scholarly journals Modelling of Average Pore Size and Porosity of Porous Polycaprolactone/Hydroxyapatite (PCL/HA) Composite Blends

2019 ◽  
Vol 9 (1) ◽  
pp. 5791-5797
Keyword(s):  
Pore Size ◽  
Average Pore Size ◽  
Effect Of Temperature ◽  
Coefficient Of Determination ◽  
Average Pore ◽  
Foaming Process ◽  
Different Temperatures ◽  
Higher Temperature ◽  
Predicted Values ◽  
Experimental Values

The objective of this paper is to develop mathematical relationship between average pore size and porosity of porous polycaprolactone/hydroxyapatite (PCL/HA) composite and investigate the combined effect of temperature and pressure of foaming process and presence of HA. Porous PCL/HA composite was prepared using supercritical carbon dioxide (ScCO2) solid state foaming process. Three different temperatures and pressures of foaming process were varied at 35°C, 40°C, 45°C and 10MPa, 20MPa, 30MPa respectively. Meanwhile weight of HA was varied at 10, 20, 30 and 40 wt%. The result from analysis of variance (ANOVA) using Microsoft Excel found that average pore size is reduced with higher pressure and content of HA presence does not significantly affect the average pore size due to poor distribution of HA. Meanwhile for porosity, higher temperature is more dominant in increasing of porosity compared to the HA content. In addition, both designed models have low values of Average Absolute Relative Deviation (%AARD) and high value of coefficient of determination (R2 ) which reflects a good and satisfying result between the experimental values and model predicted values.

scholarly journals THE EFFECT OF TEMPERATURE ON THE PERFORMANCE OF ACTIVATED CARBON OVER CATALYTIC CRACKING OF CRUDE PALM OIL

2018 ◽  
Vol 5 (1) ◽  
Author(s):  
Nazarudin Nazarudin ◽  
Ulyarti Ulyarti ◽  
Oky Alfernando ◽  
Ira Galih ◽  
Susilawati Susilawati ◽  
...  
Keyword(s):  
Activated Carbon ◽  
Palm Oil ◽  
Active Carbon ◽  
Catalytic Cracking ◽  
Effect Of Temperature ◽  
Crude Palm Oil ◽  
Carbon Catalyst ◽  
Different Temperatures ◽  
Higher Temperature ◽  
Catalyst Increase

This research was carried out to investigate the effect of temperature in carbon production on its performance in the catalystic cracking of CPO to fuel.  The carbon was produced using palm shell at 2 different temperatures (450 and 550oC).  The cracking of CPO was carried out with and without the active carbon catalyst.  The result showed that the use of catalyst increase the conversion of both gas and liquid conversion.  The use of higher temperature in the production of active carbon catalyst increased the performance of the catalyst, in particular, for the liquid conversion. Keywords :Activated carbon, catalyst, catalytic cracking, crude palm oil

Effect of temperature on the bond-slip between I-shaped steel and concrete

2021 ◽  
pp. 136943322199355
Author(s):  
Yuzhuo Wang ◽  
Bingjie Zhang ◽  
Ziqing Liu ◽  
Ying Gao ◽  
Chuanguo Fu
Keyword(s):  
Bond Strength ◽  
High Temperatures ◽  
Room Temperature ◽  
Effect Of Temperature ◽  
Bond Slip ◽  
Steel Columns ◽  
Different Temperatures ◽  
Higher Temperature ◽  
S Curve ◽  
Test Furnace

This paper presents results from an experimental study on the effect of temperature on bond strength of I-shaped steel and concrete. Eleven concrete encased steel (CES) specimens were tested by home-made fire test furnace to evaluate bond strength at various constant high temperatures (20°C600°C). The test results showed that: (1) the trend of the bond-slip curves at high temperatures were much similar to that at room temperature. Compared with room temperature specimen, the ultimate bond load and the residual bond load of specimens at high temperatures were significantly decreased. The specimens with the higher temperature had the less ultimate bond load and residual bond load. (2) In the descending stage, the P-S curve of the specimens with higher temperatures had more flat slope. The P-S curve of the specimens at the temperatures higher than 250°C had invisible descending stage. The ultimate bond load of the specimen at 600°C left with only about 5% of that at room temperature. (3) The ultimate slippages (i.e. the slippage at the ultimate bond load) of specimens at high temperatures were larger than that at room temperature, and varied from 2 to 5 mm. (4) The calculation formulas of ultimate bond load, ultimate slippage, and residual bond load at different temperatures were presented, the constitutive equations of bond-slip at different temperatures were obtained, which will provide a reference for the fire-resistant design of concrete encased steel columns.

Effect of Multiple Firing on Wear Behavior of Dental Veneering Ceramic

2008 ◽  
Vol 368-372 ◽  
pp. 1245-1247
Author(s):  
Q.P. Gao ◽  
Yong Lie Chao ◽  
F. Guo ◽  
Xin Chun Jian ◽  
C.J. Xu
Keyword(s):  
Wear Resistance ◽  
Wear Behavior ◽  
Frictional Coefficient ◽  
Wear Test ◽  
Wear Scar ◽  
Severe Wear ◽  
Significant Difference ◽  
All Ceramic ◽  
Oral Environment ◽  
Scar Width

This study investigated the effect of multiple firing on the wear behavior of dental all-ceramic veneering ceramic (Cercon). Samples were fabricated according to the manufacturer's requirement for different firing times. The wear test was operated under simulated oral environment. The results showed that multiple firing could influence wear behavior of all-ceramic Veneer. Significant difference was observed in wear scar width among different samples. All the groups except 7time-firing one showed good wear resistance with low wear rate, smooth surface and relatively constant frictional coefficient. With the increasing firing times the wear scar width became larger. The wear resistance of dental ceramic after seven times firing was significantly lower. SEM/DFM results showed the wear facets of veneering ceramic demonstrate grooves characteristic of abrasive wear. The significant change was that severe wear dominated by brittle fracture could be seen in the 7time-firing group. Multiple firing can decrease the wear resistance of dental all-ceramic Veneer, and the wear pattern has the tendency to severe wear. The possible explanation is that the microstructure and properties of all-ceramic Veneering changed during multiple firing.

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