Hydrogen-Induced Wear of Ti–6Al–4V Alloy

2012 ◽  
Vol 476-478 ◽  
pp. 566-569
Author(s):  
Bao Guo Yuan ◽  
Hai Ping Yu ◽  
Ping Li ◽  
Gui Hua Xu ◽  
Chun Feng Li ◽  
...  

The effects of hydrogen on friction and wear properties of Ti–6Al–4V alloy sliding against GCr15 steel were investigated through dry sliding friction and wear tests in atmosphere at room temperature. Wear mechanism was determined by studying the morphology and chemical element of worn surface using SEM and EDS. Results show that friction coefficient decreases slightly and wear rate increases after hydrogenation. Wear mechanism is discussed.

2008 ◽  
Vol 368-372 ◽  
pp. 961-963
Author(s):  
Hou An Zhang ◽  
Xiao Pin Hu ◽  
Wei Cheng Tan ◽  
Cun Shi

MoSi2 was prepared by SHS, and then pressed under 300 MPa at room temperature and sintered at 1600 °C for 1 h in a vacuum furnace. The tribological properties of MoSi2 against Al2O3 in the temperature range from 700°C to 1100 °C were investigated. Microphotographs and phases of the worn surface of MoSi2 were observed by SEM and XRD. Results showed that MoSi2 has well friction and wear properties below 900 °C. When temperature rises from 900 °C to 1000 °C, wear rate of MoSi2 is raised by 20.8% which is attribute to the change of wear mechanism. The main wear mechanisms of MoSi2 are adhesion and oxidation at high temperatures. When over 900 °C, because of ductile - brittle transition characteristic of this material, plastic deformation and fracture are also found on the worn surface of MoSi2. This leads to the high wear rate of MoSi2.


2012 ◽  
Vol 706-709 ◽  
pp. 1083-1088
Author(s):  
Takashi Murakami ◽  
Kunio Matsuzaki

In this study, the friction and wear properties of the Fe7Mo6-based alloy/Al2O3 tribopair were investigated at high temperatures in air and at 298 K in water. The Fe7Mo6-based alloy/Al2O3 tribopair exhibited friction coefficients as low as 0.5 at 298 K and 873 K in air. On the other hand, this tribopair exhibited higher friction coefficients at 573 K than at 298 K and 873 K. It was also found that the friction coefficients of this tribopair were approximately 0.5 in water. The Fe7Mo6-based alloy disk specimens and their paired Al2O3 ball specimens exhibited the highest specific wear rates at 873 K in air. Oxygen-rich phase was observed on the worn surfaces of all the disk specimens. Concerning the friction and wear tests at high temperatures in air, the amount of the oxygen-rich phase increased with increasing the testing temperature. In addition, a little larger amount of the oxygen-rich phase was observed on the worn surface formed at 298 K in water than that formed at 298 K in air.


2011 ◽  
Vol 2 (1) ◽  
pp. 12-18
Author(s):  
Yeczain Perez Delgado ◽  
Koen Bonny ◽  
Patrick De Baets ◽  
Patric Daniel Neis ◽  
Vanessa Rodriguez Fereira ◽  
...  

This paper presents an experimental evaluation of friction and wear properties of WC-Cocemented carbides. A comparison is made between unlubricated rotating and linearly reciprocating pin-onplate sliding pairs. The plate specimens were WC-10wt%Co grades surface finished by polishing orsequential wire-EDM steps, whereas WC-6wt%Co pins were used as counter body. The tests were carriedout at room temperature using a sliding speed of 0.30m/s and mean Hertzain contact pressures of 1.76 and2.08 GPa, i.e., normal contact loads of 15N and 25N, respectively. The worn surfaces on plate sampleswere quantified in terms of 2–D wear profiles obtained by means of surface topography scanningequipment. Wear mechanisms such as polishing and abrasion were identified using optical microscopy.Inferior tribological characteristics for wire-EDM surface finish compared to polishing were found. Higherfriction coefficient and wear levels were measured in unidirectional rotating sliding experiments comparedto linearly reciprocating test conditions.


2013 ◽  
Vol 770 ◽  
pp. 285-288
Author(s):  
Wei Hua Wei ◽  
Jiu Hua Xu ◽  
Yu Can Fu

Ti-6Al-4V alloy was hydrogenated at 800°C by thermohydrogen treatment technology. Sliding friction and wear tests were carried out in a special tribometer assembled on CA6140 turning lathe to investigate the friction and wear morphology between hydrogenated titanium alloys and WC-Co cemented carbides. The morphological analyses of the worn surface were made by scanning electron microscope. It was found that the friction coefficient and the friction area temperature of the pair both firstly decreased and then increased with the increase of hydrogen content, and the friction coefficient decreased and the friction area temperature increased with increasing sliding speed. The main wear morphologies of the unhydrogenated alloys were serious plastic deformation, ploughing, adhesion tearing pit and fatigue microcrack, but the main wear morphologies of the hydrogenated alloys were boundary of plastic extension, slight scratch and slight adhesion tearing. Besides, the main wear morphology of the tool corresponding to unhydrogenated alloys was massive spalling, but the main wear morphology of the tool corresponding to the titanium alloy with 0.29% hydrogen content was punctate spalling.


2006 ◽  
Vol 510-511 ◽  
pp. 186-189
Author(s):  
Han Young Lee ◽  
Bum Rae Cho

Plate-on-disc type sliding friction and wear test was conducted to investigate the friction and wear properties of mullite reinforced composite (M composite), and compared with glass fiber reinforced composite (GF composite). The friction and wear test revealed that M composite has good wear resistance under mild sliding conditions, but the wear rate gradually increases under severe sliding conditions. M composite exhibited higher friction coefficient than GF composite at room temperature and maintained the friction coefficient stably at higher temperatures. The composite film formed on counter material against M composite showed influences on the friction and wear properties under severe sliding conditions.


Metals ◽  
2019 ◽  
Vol 9 (3) ◽  
pp. 356 ◽  
Author(s):  
Xuewei Zhu ◽  
Xiaofeng Wei ◽  
Yuxiang Huang ◽  
Fu Wang ◽  
Pengpeng Yan

NiCr/hBN self-lubricating composites with hBN solid-lubricant contents of 8%, 9%, 10%, 11%, and 12% (mass fractions) were prepared by powder-metallurgy method. Their tribological properties at room temperature and 600, 700, and 800 °C were studied. SEM and XRD were performed to analyze their wear-surface morphology and abrasive-dust composition. Results indicate that the NiCr/hBN self-lubricating composites have favorable tribological properties at room temperature and 600 °C. The optimum comprehensive friction and wear performance are achieved at 10% hBN, and the main wear mechanism is abrasive wear. At 700 and 800 °C, the friction and wear properties of NiCr/hBN self-lubricating composites obviously decline. The wear surface experiences oxidation and the spinel oxides Cr2O3, NiCr2O4, and CrBO3 are formed. The main wear mechanism becomes combined scratching and glue form of adhesive wear, leading to greatly increased wear rate for the NiCr/hBN sel-lubricating composites.


2012 ◽  
Vol 619 ◽  
pp. 536-540
Author(s):  
Jia Qing Liang ◽  
Chang Sheng Li ◽  
Hua Tang ◽  
Yi Zhang ◽  
Wen Jing Li ◽  
...  

Nb1-xTixSe2(x=0~1) micro/nano-particles have been successfully prepared via solid-state thermal (750°C) reaction between microsized Nb, Ti with Se powders under seal environment in a seal quartz tube and characterization by X-ray diffractometer and scanning electron microscopy. It was found that the morphologies of the as-prepared products changed from microplates to micro-nanoparticles or aggregations composed of layer structure with the doping of Ti. And the amount of regular hexagonal microplates evidently reduced and nanoscaled particles increased with the increase of the contents of Ti dopant within a certain limit (1-20 atwt. %). The tribological properties of the as-prepared products as additives in paraffin were investigated by UMT-2 multispecimen tribotester. By the addition of Nb1-xTixSe2micro/nanoparticles in paraffin, the antiwear ability was improved and the friction coefficient was decreased. The paraffin with Nb1-xTixSe2micro/nanoparticles showed better tribological properties than that with pure NbSe2. A combination of the molecule-bearing mechanism of sliding friction, and fill in-repair work between the rubbing surfaces can explain the good friction and wear properties of Nb1-xTixSe2micro/nanoparticles.


2008 ◽  
Vol 368-372 ◽  
pp. 1092-1095 ◽  
Author(s):  
Han Ning Xiao ◽  
Ji Xiang Yin ◽  
Tetsuya Senda

Friction and wear tests of Al2O3 and SiC were conducted from room temperature to 1200°C both in air and in vacuum. Results show that the wear mechanism of Al2O3 is dominated by micro fracture, debris abrasive and delamination at temperatures below 600 °C, while is controlled by plastic deformation and recrystallization among 600~1200 °C, resulting in an obvious decrease of wear loss. The wear rate and surface microstructure of SiC are closely depending on the testing temperature, atmosphere and contact pressure. Oxidation of SiC at elevated temperatures plays important role on the wear rate. Self lubrication of both Al2O3 and SiC at high temperatures was observed, which is mainly depending on the formation of a specific surface layer composed of nano-particles or very thin glassy film.


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