Tribokemi av smrjningsmedel under hgt tryck Joel Andersson High - PowerPoint PPT Presentation

Tribokemi av smörjningsmedel under högt tryck Joel Andersson High pressure spectroscopy lab Division of Physics,TFM Luleå University of Technology

This project is conducted in High Pressure Spectroscopy Laboratory (Materials Physics group) Supervisor: Professor Alexander Soldatov Project student Shuai Wei (AMASE program) High pressure spectroscopy lab High pressure spectroscopy lab Division of Physics,TFM Division of Physics,TFM Luleå University of Technology Luleå University of Technology

Summary Introduction, Motor oil Additives Methods and materials Results Conclusions High pressure spectroscopy lab Division of Physics,TFM Luleå University of Technology

Introduction: Motor oil additives Advanced additives are used to enhance the properties of lubricants One of them is Zinc Dialkyl Dithiophosphate, ZDDP High pressure spectroscopy lab Division of Physics,TFM Luleå University of Technology

ZDDP as an additive First used in the late 30:s. Anti-wear properties discovered in the 40: s. Extensively studied till today. High pressure spectroscopy lab Division of Physics,TFM Luleå University of Technology

ZDDP and a Tribofilm Typical conditions for tribofilm formation: 6-9 GPa 100-250 °C High pressure spectroscopy lab Division of Physics,TFM Luleå University of Technology The image is from: H. Spikes. Tribology Letters, Vol. 17, No. 3, 2004

Tribochemistry of ZDDP Solution decomposition of ZDDP Thermal decomposition of ZDDP (at high temperature) Cross-linkage at high pressures High pressure spectroscopy lab Division of Physics,TFM Luleå University of Technology

Decomposition in solution High pressure spectroscopy lab Division of Physics,TFM Luleå University of Technology Image from: H. Spikes. Tribology Letters October 2004 .

Thermal decomposition Mercaptides (Thiols) Olefins (alkanes) Alkyl Sulphides H 2 S Zinc phosphate High pressure spectroscopy lab Division of Physics,TFM Luleå University of Technology

Cross-linkage of Zinc phosphate Starting structure After one compression cycle Cross-linkage at 7GPa High pressure spectroscopy lab Division of Physics,TFM Luleå University of Technology Nicholas J Mosey; Martin H Müser; Tom K Woo Science, 2005; 307, 5715

Project objectives Understanding the tribochemistry of ZDDP in solution To map the pressures and temperatures that induce change of ZDDP solution High pressure spectroscopy lab Division of Physics,TFM Luleå University of Technology

Methods and Materials ZDDP in hexadecane Diamond Anvil Cell Confocal Raman spectroscopy High pressure spectroscopy lab Division of Physics,TFM Luleå University of Technology

Materials Hexadecane(C 16 H 34 ) ZDDP (Zn(S 2 P(OH) 2 ) 2 High pressure spectroscopy lab Division of Physics,TFM Luleå University of Technology

Raman spectroscopy hυ 1 hυ hυ hυ 2 hυ 3 High pressure spectroscopy lab Division of Physics,TFM Luleå University of Technology

High Pressure Diamond Anvil Cell Pressure up to 3 Mbar Temperature up to 600 °C Incoming light Diamond anvil Gasket (sample chamber) Sample chamber High pressure spectroscopy lab Division of Physics,TFM Luleå University of Technology

Results Reference spectra, measurements of substances at ambient conditions. Definition of vibrations to follow in high pressure High pressure spectroscopy lab Division of Physics,TFM Luleå University of Technology

Raman spectra of ZDDP and Hexadecane High pressure spectroscopy lab Division of Physics,TFM Luleå University of Technology

Raman spectra of saturated solution High pressure spectroscopy lab Division of Physics,TFM Luleå University of Technology

Raman spectra in the 800-900cm -1 region 830 cm -1 peak High pressure spectroscopy lab Division of Physics,TFM Luleå University of Technology

Raman spectra in the 900-1000cm -1 region 830 cm -1 peak High pressure spectroscopy lab Division of Physics,TFM Luleå University of Technology

Spectral subtraction: ZDDP-Hexadecane solution High pressure spectroscopy lab Division of Physics,TFM Luleå University of Technology

Conclusion We can distinguish the prominent ZDDP peaks at 963 and 830 cm -1 Analysis of these peaks indicates that they originate from Phosphorus-Oxygen and Zinc- Oxygen bonds. We will follow these peaks evolution at high pressure High pressure spectroscopy lab Division of Physics,TFM Luleå University of Technology

Future work High pressure study of ZDDP in different solvents High pressure and High temperature examination of ZDDP in solvent High pressure spectroscopy lab Division of Physics,TFM Luleå University of Technology

Collaboration Professor Roland Larsson (Machine Elements Division, TFM, LTU) Dr. Rihard Pasaribu, Dr. Piet Lugt (SKF R&D division, Holland) Acknowledgements Shuai Wei (AMASE project student) Andreas Müller (former group member, now at MPI Stuttgart)) Matias Mases (group member) High pressure spectroscopy lab Division of Physics,TFM Luleå University of Technology

Thank you for your attention Questions? High pressure spectroscopy lab Division of Physics,TFM Luleå University of Technology