Tribological behavior and wear mechanisms of MoSi2-base composites sliding against AA6063 alloy at elevated temperature

Owing to its outstanding physical and mechanical properties, polycrystalline diamond (PCD) is ideal for cutting titanium alloys. However, the high temperature and stress caused by the interaction of tool surface and chip flow lead to different types of wear. This paper investigates the wear mechanisms of PCD tools in three different tribological regions: sticking zone, transition zone, and sliding zone, when machining titanium alloy Ti6Al4V. The tribological behavior of PCD tools in the wear processes were analyzed through both experiments and theoretical calculations. Analytical models of stresses and temperature distribution were developed and validated by turning experiments. PCD tools, consisting of diamond grains of different sizes: CTB002 (2 μm), CTB010 (10 μm), and CTM302 (2–30 μm), were used to cut Ti6Al4V at the normal cutting speed of 160 m/min and high cutting speed 240 m/min. It was found that adhesion, abrasion and diffusion dominated the wear process of PCD tools in different worn regions. Microscopic characters showed that the wear mechanisms were different in the three tribological regions, which was affected by the distribution of stresses and temperature. “Sticking” of workpiece material was obvious on the cutting edge, abrasion was severe in the transition zone, and adhesion was significant in the sliding zone. The shapes and morphological characters in different worn regions were affected by the stresses distribution and the types of PCD materials.

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Preparation and Tribological Behavior of Self-Lubrication Composites Ni-W-Cr-Fe-Cu-MoS2-Graphite at Elevated Temperature

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.668.3 ◽

2013 ◽

Vol 668 ◽

pp. 3-8 ◽

Cited By ~ 1

Author(s):

Jian Rong Sun ◽

Chang Sheng Li ◽

Hua Tang ◽

Zhi Cheng Guo ◽

Jin Ying Zi Liu

Keyword(s):

Tensile Strength ◽

Elevated Temperature ◽

Powder Metallurgy ◽

Friction Coefficient ◽

Tribological Properties ◽

Room Temperature ◽

Tribological Behavior ◽

Strengthening Effect ◽

Wear Rates ◽

Increasing Temperature

The composites of Ni-W-Cr-Fe-Cu-MoS2-Graphite with nano-MoS2 were prepared by powder metallurgy. Its tribological properties were investigated using the UTM-2 Nano+Micro Tribometer from room temperature to 600°C. The effects of amount of MoS2 and Ni-W-Cr prealloy powder, load, and temperature on the tribological properties were investigated and discussed. The results indicated that the addition of 43~45wt.% Ni-W-Cr prealloy powder had a strengthening effect on the hardness, anti-press and tensile strength. The tensile strength of the composite decreases with the addition of Nano-MoS2 and graphite, and the friction coefficient decrease with increase of the additives over the wide temperature range of 25°C∼600°C. The friction coefficients and wear rates of the composites reach the optimization value at 2.5wt.% MoS2,While its wear rates increase with the increasing temperature and load.

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Tribological Behavior of Si3N4/Ti3SiC2Contacts Lubricated by Lithium-Based Ionic Liquids

Advances in Materials Science and Engineering ◽

10.1155/2014/863230 ◽

2014 ◽

Vol 2014 ◽

pp. 1-8 ◽

Cited By ~ 1

Author(s):

Haizhong Wang ◽

Zenghong Song ◽

Dan Qiao ◽

Dapeng Feng ◽

Jinjun Lu

Keyword(s):

Ionic Liquids ◽

Elevated Temperature ◽

Tribological Properties ◽

Friction And Wear ◽

Room Temperature ◽

Tribological Behavior ◽

Tribological Performance ◽

Experimental Conditions ◽

Thermal Stabilities ◽

Protective Films

The tribological performance of Si3N4ball sliding against Ti3SiC2disc lubricated by lithium-based ionic liquids (ILs) was investigated using an Optimol SRV-IV oscillating reciprocating friction and wear tester at room temperature (RT) and elevated temperature (100°C). Glycerol and the conventional imidazolium-based IL 1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (L-F106) were used as references under the same experimental conditions. The results show that the lithium-based ILs had higher thermal stabilities than glycerol and lower costs associated with IL preparation than L-F106. The tribotest results show that the lithium-based ILs were effective in reducing the friction and wear of Si3N4/Ti3SiC2contacts. [Li(urea)]TFSI even produced better tribological properties than glycerol and L-F106 both at RT and 100°C. The SEM/EDS and XPS results reveal that the excellent tribological endurance of Si3N4/Ti3SiC2contacts lubricated by lithium-based ILs was mainly attributed to the formation of surface protective films composed of various tribochemical products.

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Tribological behavior of Mg-WC nano-composites at elevated temperature

Materials Research Express ◽

10.1088/2053-1591/ab2379 ◽

2019 ◽

Vol 6 (8) ◽

pp. 0865c6 ◽

Cited By ~ 5

Author(s):

Sudip Banerjee ◽

Suswagata Poria ◽

Goutam Sutradhar ◽

Prasanta Sahoo

Keyword(s):

Elevated Temperature ◽

Tribological Behavior ◽

Nano Composites

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Tribological Behavior of Mg-Mg2Si In Situ Composite

Materials Science Forum ◽

10.4028/www.scientific.net/msf.710.401 ◽

2012 ◽

Vol 710 ◽

pp. 401-406

Author(s):

Kumaraswamy Kaliamma Ajith Kumar ◽

Uma Thanu Subramonia Pillai ◽

Bellambettu Chandrasekhara Pai ◽

Madhusudan Chakraborty

Keyword(s):

Elevated Temperature ◽

Wear Rate ◽

Grain Boundary ◽

Tribological Behavior ◽

Grain Boundary Sliding ◽

Dry Sliding ◽

Boundary Sliding ◽

Si Content ◽

State Processing

Mg-Mg2Si in-situ composites by the addition of Si in Mg have become more attractive since the Mg2Si phase impedes the grain boundary sliding at elevated temperature because of its inherent properties which greatly improve the heat and wear resistances. In the present work, Mg-Mg2Si composites have been prepared by the liquid state processing with different amount of silicon additions. The microstructure and dry sliding tribological behavior of the composites have been studied. SEM studies reveal the wear mechanisms involved in these composites. The results indicate that wear rate of the composites is a function of Mg2Si content in the composite. The effect of Mg2Si morphology and distribution on the overall mechanism is also discussed.

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Study on Tribological Behavior and Mechanisms of Weldox960 Steel

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.415-417.2191 ◽

2011 ◽

Vol 415-417 ◽

pp. 2191-2195

Author(s):

Ye Fa Tan ◽

Bin Cai ◽

Long He ◽

Sheng Qiang Hao ◽

Hua Tan ◽

...

Keyword(s):

Plastic Deformation ◽

Abrasive Wear ◽

Work Hardening ◽

Wear Mechanisms ◽

Sliding Friction ◽

Tribological Behavior ◽

Critical Value ◽

Dry Sliding ◽

Wear Rates ◽

Oxidation Wear

Weldox960 steel is widely used in mechanical structure of military equipments as anti-wear parts. The tribological behavior and mechanisms of weldox960 steel were investigated under dry sliding friction conditions. The results show that friction coefficient of the steel increases from 0.268 to 0.365 with the increase of load. When the loads are smaller than 8N, the wear rates of the steel are in the range of 0.57~0.67×10-3 mm3/m, and the wear mechanism is multi-plastic deformation wear. If the loads are bigger than 10N, the wear rates increase to the range of 1.29~1.43×10-3 mm3/m, and the wear mechanisms change into delamination of the work-hardening layer and abrasive wear. The friction coefficients keep in a steady state of about 0.31 when the sliding speeds change from 0.05m/s to 0.2m/s. At the low speeds of 0.05m/s and 0.1 m/s, the wear rates are in the range of 1~1.3×10-3 mm3/m and the wear mechanisms are multi-deformation wear and abrasive wear. When the sliding speed increases to a critical value of 0.15m/s, the wear rates increase to 6.2×10-3 mm3/m and the wear mechanisms change into fatigue delamination of the work-hardening layer and multi-plastic deformation wear as well as oxidation wear.

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Tribological Behavior of DLC Films by RF-PECVD at the Elevated Temperature

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.353-358.1781 ◽

2007 ◽

Vol 353-358 ◽

pp. 1781-1784

Author(s):

Yong Kyung Cho ◽

Yun Ha Shin ◽

Sung Hoon Jeong ◽

Young Ze Lee

Keyword(s):

Raman Spectroscopy ◽

Elevated Temperature ◽

Vapor Deposition ◽

Room Temperature ◽

Tribological Behavior ◽

Chemical Vapor ◽

Diamond Like Carbon ◽

Radio Frequency Plasma ◽

Frequency Plasma ◽

Higher Temperature

The tribological behaviors of Diamond-like carbon (DLC) films, prepared by the radio frequency plasma enhanced chemical vapor deposition (RF-PECVD) method, were studied in the room temperature and the elevated temperature. The ball-on-disk tests with DLC films on steel specimens were conducted at a sliding speed of 60 rpm, a load of 10 N, and surrounding temperatures of 25°C and 75°C. The results show that the coefficients of friction and the amounts of wear of DLC films were decreased at higher temperature. After tests the wear tracks of hydrogenated DLC film were analyzed by Raman spectroscopy.

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