scholarly journals Dry Rolling/Sliding Wear of Bainitic Rail Steels under Different Contact Stresses and Slip Ratios

Materials ◽  
2020 ◽  
Vol 13 (20) ◽  
pp. 4678
Author(s):  
Jiapeng Liu ◽  
Yingqi Li ◽  
Yinhua Zhang ◽  
Yue Hu ◽  
Lubing Shi ◽  
...  
Keyword(s):  
Friction Coefficient ◽  
Abrasive Wear ◽  
Contact Stress ◽  
Wear Mechanism ◽  
Rolling Contact Fatigue ◽  
Contact Fatigue ◽  
Rolling Contact ◽  
Wear Loss ◽  
Fatigue Wear ◽  
Slip Ratio

This study aims to deeply understand the effect of contact stress and slip ratio on wear performances of bainitic rail steels. The results showed that the wear loss increased as the contact stress and slip ratio increased. Based on the surface damage morphology and microstructural analyses, it revealed that the rolling contact fatigue wear mechanism played a significant role under the low slip ratio, but the dominant wear mechanism transferred to the abrasive wear at the high slip ratio. Meanwhile, the bainitic steel specifically presented worse wear resistance under the abrasive wear mode. Compared with the influence of a slip ratio, the increase in contact stress led to severer plastic flows and contributed to the propagation of cracks. In addition, the contact stress and slip ratio had the opposite effect on the friction coefficient, that is, the friction coefficient of bainitic steels behaved the inverse proportion with the contact stress, but positive proportion with the slip ratio. At last, the increase in slip ratio had more significant effect on the reduction of retained austenite (RA) than the enlargement of contact stress due to the fact that the RA would probably be removed before the martensitic transformation occurred under the abrasive wear mechanism.

Effect of Rotation Speeds on Friction Coefficients of PPS Race-PTFE Retainer Hybrid Polymer Thrust Bearings under Dry Contact

2013 ◽  
Vol 418 ◽  
pp. 205-208 ◽  
Author(s):  
Xiao Chen Shi ◽  
Koshiro Mizobe ◽  
Yuji Kashima ◽  
Katsuyuki Kida
Keyword(s):  
Friction Coefficient ◽  
Rolling Contact Fatigue ◽  
Contact Fatigue ◽  
Fatigue Tests ◽  
Rolling Contact ◽  
Wear Loss ◽  
Hybrid Polymer ◽  
Thrust Bearings ◽  
Dry Contact ◽  
Thrust Load

In the previous study on PPS race-PTFE retainer Hybrid polymer bearings, the relationship between thrust load, rotation speeds and wear loss under dry condition was investigated. It was found that the wear loss obviously changed under the thrust load ranging from 400N to 500N at the rotation speeds of 450rpm and 600rpm. The object of this study is to observe the friction coefficient at the rotation speeds ranging from 450rpm and 600N under thrust load of 400N. Rolling contact fatigue tests were performed and it was concluded that friction coefficient decreases with the rotation speeds.

Friction Coefficient and Wear of PEEK-PTFE Hybrid Radial Ball Bearings under Dry Conditions

2021 ◽  
Vol 1020 ◽  
pp. 114-119
Author(s):  
Kazutoshi Hiraki ◽  
Koshiro Mizobe ◽  
Takahiro Matsueda ◽  
Yuji Kashima ◽  
Katsuyuki Kida
Keyword(s):  
Friction Coefficient ◽  
Rolling Contact Fatigue ◽  
Contact Fatigue ◽  
Fatigue Tests ◽  
Rolling Contact ◽  
Frictional Heat ◽  
Wear Loss ◽  
Ball Bearings ◽  
Operation Temperature ◽  
Dry Conditions

In this paper, in order to investigate friction coefficient and wear of PEEK-PTFE hybrid radial bearings, rolling contact fatigue tests were performed under radial loads ranging from 93N to 387N at 600rpm in dry conditions. It was found that friction coefficients were 0.013 to 0.032 throughout the tests. Operation temperature followed the change in the friction coefficient, and PEEK-PTFE radial ball bearings exhibited stable performance even though the temperature locally approached 100 °C due to frictional heat. Moreover, wear loss of bearing components excluding alumina balls increased exponentially with increase of load.

Surface Observation of Induction-Heated 13Cr-2Ni-2Mo Stainless Steel after Interrupted Fatigue Testing under Rolling Contact Stress in Water

2021 ◽  
Vol 315 ◽  
pp. 72-76
Author(s):  
Koshiro Mizobe ◽  
Takahiro Matsueda ◽  
Gakuto Shinohara ◽  
Takuya Shibukawa ◽  
Katsuyuki Kida
Keyword(s):  
Stainless Steel ◽  
Contact Stress ◽  
Contact Area ◽  
Contact Surface ◽  
Fatigue Testing ◽  
Wear Behavior ◽  
Rolling Contact Fatigue ◽  
Contact Fatigue ◽  
Rolling Contact ◽  
Wear Loss

In order to investigate the wear behavior of induction-heated 13Cr-2Ni-2Mo stainless steel, we performed the rolling contact fatigue (RCF) tests in water. We interrupted the RCF test at each 1.0×105 cycles and measure the wear loss and observed the contact surface. After the RCF tests, we found the oxygen concentration area in the contact area.

Effects of slip ratio and contact stress on rolling contact fatigue of defected rail materials

2021 ◽  
pp. 105817
Author(s):  
X.J. Zhao ◽  
Q. Chen ◽  
Y.S. Liu ◽  
X.Y. Qiu ◽  
E. Meli ◽  
...  
Keyword(s):  
Contact Stress ◽  
Rolling Contact Fatigue ◽  
Contact Fatigue ◽  
Rolling Contact ◽  
Slip Ratio

Observation of Cracks of PEEK Polymer Thrust Bearings under Rolling Contact Fatigue in Water

2016 ◽  
Vol 703 ◽  
pp. 172-177 ◽  
Author(s):  
Xiao Chen Shi ◽  
Masaya Orito ◽  
Yuji Kashima ◽  
Koshiro Mizobe ◽  
Katsuyuki Kida
Keyword(s):  
Corrosion Resistance ◽  
Friction Coefficient ◽  
Cross Sections ◽  
Rolling Contact Fatigue ◽  
Contact Fatigue ◽  
Rolling Contact ◽  
Light Weight ◽  
Low Friction ◽  
High Corrosion Resistance ◽  
Thrust Bearings

Considering the advantages on light weight, low friction coefficient, high corrosion resistance and electric insulation, polymer bearings are widely used under certain environments, where the toughness like metal bearings is not necessary. In our previous study, it was concluded that the main reason for PEEK thrust bearings failure in water was flaking due to surface crack propagation. In the present study, crack observations were made on groove surfaces and cross sections along both radial and rolling directions in order to find the relation between cracks and flaking failures.

Effect of PTFE Retainer on Friction Coefficient in Polymer Thrust Bearings under Dry Contact

2013 ◽  
Vol 683 ◽  
pp. 90-93 ◽  
Author(s):  
Koshiro Mizobe ◽  
Takashi Honda ◽  
Hitonobu Koike ◽  
Edson Costa Santos ◽  
Yuji Kashima ◽  
...  
Keyword(s):  
Friction Coefficient ◽  
Rolling Contact Fatigue ◽  
Contact Fatigue ◽  
Fatigue Tests ◽  
Rolling Contact ◽  
Low Friction ◽  
Friction Forces ◽  
Thrust Bearings ◽  
Dry Contact

Polyetheretherketone (PEEK) is a tough semi-crystalline thermoplastic polymer with excellent mechanical properties. While abilities of polyphenylenesulfide (PPS) are similar to PEEK, former material cost was lower than later. Polytetrafluoroethylene (PTFE) is well known because of its low friction coefficient and self lubrication ability. The objective of this study is to observe the friction coefficient of hybrid bearings, PTFE retainer sandwiched with PPS-races or PEEK-races. Rolling contact fatigue tests were performed and in situ friction forces wear measured. It is concluded that the PTFE retainer reduced friction coefficient.

Research on the Approach for the Assessment of Subsurface Rolling Contact Fatigue Damage

2013 ◽  
Vol 395-396 ◽  
pp. 845-851
Author(s):  
Xiao Feng Qin ◽  
Da Le Sun ◽  
Li Yang Xie
Keyword(s):  
Shear Stress ◽  
Friction Coefficient ◽  
Fatigue Damage ◽  
Stress Ratio ◽  
Rolling Contact Fatigue ◽  
Contact Fatigue ◽  
Rolling Contact ◽  
Critical Stresses ◽  
Orthogonal Shear Stress

In this paper, the distribution of different critical stresses, which were used in previous correlation articles for the assessment of subsurface rolling contact fatigue damage, was analyzed. The rationality of orthogonal shear stress was selected as the key stress controlling the subsurface rolling contact fatigue damage was clarified. Base on the linear fatigue damage accumulative theory and the modification equation for the range of asymmetrical stress, the influence of friction on subsurface rolling contact fatigue damage was studied. The results show that the subsurface orthogonal shear stress is a completely symmetrical stress when the friction coefficient is zero, while it is an asymmetrical stress with considering the friction. The stress ratio of subsurface orthogonal shear stress and subsurface rolling contact fatigue damage is increased with the increasing of friction.

Study on wear and rolling contact fatigue behaviors of wheel/rail materials under different slip ratio conditions

Wear ◽  
2016 ◽  
Vol 366-367 ◽  
pp. 13-26 ◽  
Author(s):  
L. Ma ◽  
C.G. He ◽  
X.J. Zhao ◽  
J. Guo ◽  
Y. Zhu ◽  
...  
Keyword(s):  
Rolling Contact Fatigue ◽  
Contact Fatigue ◽  
Rolling Contact ◽  
Slip Ratio

scholarly journals Effect of Gas Nitriding on Interface Adhesion and Surface Damage of CL60 Railway Wheels under Rolling Contact Conditions

Metals ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 911
Author(s):  
Qiang Wu ◽  
Tao Qin ◽  
Mingxue Shen ◽  
Kangjie Rong ◽  
Guangyao Xiong ◽  
...  
Keyword(s):  
Wear Behavior ◽  
Rolling Contact Fatigue ◽  
Contact Fatigue ◽  
Rolling Contact ◽  
Wheel Surface ◽  
Fatigue Wear ◽  
Material Loss ◽  
Surface Protection ◽  
Gas Nitriding ◽  
Railway Wheels

The influence of surface gas nitriding on wheel/rail rolling contact fatigue and wear behavior of CL60 wheel was studied on a new rolling contact fatigue/wear tester (JD-DRCF/M). The failure mechanisms of the wheel/rail surface after the gas nitriding and without gas nitriding on the wheel surface were compared and analyzed. The results show that the wheel with gas nitriding could form a dense and hard white bright layer which was approximately 25 μm thick and a diffusion layer which was approximately 70 μm thick on the wheel surface. Thus, the gas nitriding on the railway wheel not only significantly improved the wear resistance on the surface of the wheel, but also effectively reduced the wear of the rail; the results show that the material loss reduced by 58.05% and 10.77%, respectively. After the wheel surface was subjected to gas nitriding, the adhesive coefficient between the wheel/rail was reduced by 11.7% in dry conditions, and was reduced by 18.4% in water media, but even so, the wheel with gas nitriding still could keep a satisfactory adhesive coefficient between the wheel/rail systems, which can prevent the occurrence of phenomena such as wheel-slip. In short, the gas nitriding on the wheel surface can effectively reduce the wear, and improve the rolling contact fatigue resistance of the wheel/rail system. This study enlarges the application field of gas nitriding and provides a new method for the surface protection of railway wheels in heavy-duty transportation.

scholarly journals Study on Friction and Lubrication Characteristics of Surface with Unidirectional Convergence Texture

Coatings ◽  
2019 ◽  
Vol 9 (12) ◽  
pp. 780 ◽  
Author(s):  
Chenchen Li ◽  
Xuefeng Yang ◽  
Shouren Wang ◽  
Yanjun Wang ◽  
Chongyang Lu ◽  
...  
Keyword(s):  
Friction Coefficient ◽  
Abrasive Wear ◽  
Simulation Analysis ◽  
Dynamic Pressure ◽  
Contact Fatigue ◽  
Hydrodynamic Pressure ◽  
Surface Friction ◽  
Textured Surface ◽  
Fatigue Wear ◽  
Lubrication Performance

In order to study the influence of texture on the wear and lubrication performance of the surface of the tools, three kinds of textures with unidirectional convergence morphology were processed on the surface of the samples, and each texture was designed with different area occupancy ratios. Simulation analysis shows that, owing to the reflow and convection effect of liquid in the texture, the lubricating film flowing through the textured surface has a high hydrodynamic pressure value, and the semicircular ring texture is the most prominent. By comparing the friction coefficient, when the area occupancy ratio of texture on the surface is 10%, the surface of the samples with different morphology has the lowest coefficient of friction; the friction coefficient of the semicircular ring textured surface is especially very low. Surface textures reduce the direct contact area between the friction pairs, and generate dynamic pressure lubrication and secondary lubrication, so that the surface friction coefficient of the samples is obviously reduced. The surfaces of the non-textured samples have abrasive wear and contact fatigue wear, and the surfaces of the textured samples have adhesive wear, abrasive wear, and cavitation.

Sign in / Sign up

Export Citation Format

Share Document