Skip to main content

Novel Surfaces, Interfaces, Lubricants

Interfaces examine the effectiveness of a surface design, and surface durability decides the functionality and efficiency of interfaces.

Texture Design and Fabrication

Texture Design and Fabrication

Properly designed textures can help improve the tribological performances of components, in terms of friction and wear reduction, enhanced lubrication, improved frictional heat transfer, and scuffing prevention. However, textures bring several additional degrees of freedom into surface design, and at the end, range of effectiveness, durability, and sensitivity to operating conditions may only offer certain windows to the acceptable performances of textured surfaces. Scale is another issue, and the match among texture dimensions, roughness, the pattern of surface interaction, and the level of interface separation is the bottom line for designing textures for lubrication enhancement. Model-based virtual texturing is an effective means to “prerun” surfaces under design in sufficiently wide conditions at the interfaces for which they are designed. Over the years Prof. Wang and her team found that the texture design rules are different for the applications in different regimes of lubrication, concerning lubrication enhancement and/or adhesion prevention with the needed mechanisms for hydrodynamics or for stiction control. Professor Wang and collaborators have designed novel surfaces for the products or tools used at Ford, Boeing, Caterpillar, GM, Nissan, and Mazda. 

Related Publications and Patents

  1. Wang, Q. and Zhu, D., 2005, “Virtual Texturing: Modeling the Performance of Lubricated Contacts of Engineered Surfaces,” ASME Journal of Tribology, Vol. 127, pp. 722-728. https://doi.org/10.1115/1.2000273.
  2. Ren, N, Nanbu, T., Yasuda, Y., Zhu, D., and Wang, Q., 2007, “Micro Textures in Concentrated Conformal-Contact Lubrication: Effect of Distribution Patterns,” Tribology Letters, Vol. 28, pp 275-285.
  3. Nanbu, T., Ren, N., Yasuda, Y., Zhu, D., and Wang, Q., 2008, “Micro Textures in Concentrated Conformal-Contact Lubrication: Effects of Texture Bottom Shape and Surface Relative Motion,” Tribology Letters, Vol. 29, 241 – 252.
  4. He, B., Ghosh, G., Chung, Y. W., and Wang, Q., 2010, “Effect of Melting and Microstructure on the Microscale Friction of Silver-Bismuth Alloys,” Tribology Letters, Vol. 38, pp.275-282. https://link.springer.com/article/10.1007/s11249-010-9606-4.
  5. Greco, A., Martini, A., Liu, Y., Lin, C., and Wang, Q., 2010, “Rolling Contact Fatigue Performance of Vibro-Mechanical Textured Surfaces,” Tribology Transactions, Vol. 53, pp. 610-620.
  6. Greco, A., Raphaelson, S. Ehmann, K, Lin, C., and Wang, Q., 2009, “Surface Texturing of Tribological Interfaces Using the Vibromechanical Texturing Method,” Journal of Manufacturing Science and Technology, Vol. 131 / 061005-1-8.
  7. Ling, T., D., Liu, P., Xiong, S., Grzina, D., Cao, J., Wang, Q., Xia, Z., Talwar, R., 2013, “Surface Texturing of Drill Bits for Adhesion Reduction and Tool Life Enhancement,” Tribology Letters, Vol. 52, PP. 113-122. http://link.springer.com/article/10.1007%2Fs11249-013-0198-7.
  8. Aktürk, D., Liu, P., Cao, J., Wang, Q., Xia, Z., Talwar, R., Grzina, D., and Merklein, M., 2015, “Friction Anisotropy of Aluminum 6111-T4 Sheet with Flat and Laser-Textured D2 Tooling,” Tribology International, Vol. 81, pp. 333-340.   http://www.sciencedirect.com/science/article/pii/S0301679X14003259.
  9. Liu, Z., Gu, T., Pickens, D., Nishino, T., and Wang, Q., 2021, “Housing Profile Design for Improved Apex Seal Lubrication Using a Finite-Length Roller EHL Model,” Journal of Tribology, Vol. 143 (8), 082301, https://doi.org/10.1115/1.4048998
  10. Khan, M. A, Wang, Q., Fernandez, J., Li, Z., and Liu, Y., 2021 “Friction at Ring-Liner Interface Analyzed with a Systematic Surface Characterization,” Tribology Transactions, Vol. 64(6), pp. 1064-1078, https://doi.org/10.1080/10402004.2021.196466
  11. Grzina, D., Talwar, R., Cao, J., Wang, Q., Xia, C., Ling, T. D., and Liu, P., granted 2015, Cutting Tools with Texture Surfaces, US Patent No. 9144845.
  12. Xia, C., Talwar, R., Cao, J., Wang, Q., Ling, T. D., and Liu, P., granted 2013, Forming Tools Having Textured Surfaces. US Patent No. 9,321,090 B2.
  13. Wang, Q. and Liu, Z., Profile and Surface Texture Designs for Roller Sliding Contact System, in process. Provisional application May 2017; Full application, May 2017, Patent app. No. 16/613484

Lubricant Design and Innovation

Base-fluid design carries the major weight for the quality of a lubricant, especially for that used to lubricate the systems of an electrical vehicle. Simple formulas that link the performance metrics to the molecular structure parameters of a fluid are welcome by industrial designers. Professor Wang and collaborators have studied several different types of base fluids, such as siloxanes, alphaolefins, and a number of traction fluids through testing, data fitting, and molecular dynamics simulations, and developed 1) a calculation module that relates density, viscosity and friction with siloxane structures of a wide range of parameter (chain length, branch length and density,  and end groups), with optimized products made by collaborative chemists, 2) an equation for the critical viscous shear stress to cause shear-thinning as a function of mass of PAOs, 3) a formula to calculate the viscosity-pressure coefficient, crucial to traction fluids, from experimentally measure shear stress, and 4) an expression of pour point in terms of fluid structural parameters, such as the ratio of solvent accessible surface area to the total number of carbons, the numbers of carbons in the rings, the CH3 group, the CH2 group, the CH group, and the number of quaternary carbons.  These formulas and equations have been used in Dow Corning then and Valvoline for fluid designs. 

Related Publications and Patents

  1. Zolper, T., Afif, S., Chen, C., Jungk, M., Stammer, A., Stoegbauer, H., Marks, T., Chung, Y. W., and Wang, Q., 2013, “Energy Efficient Siloxane Lubricants Utilizing Temporary Shear Thinning,” Tribology letters, 49, Issue 3, pp 525-538, DOI 10.1007/s11249-012-0093-7.
  2. Zolper, T., Shiller, P., Junkl, M., Marks, T., Chung, Y.W., Greco, A., Doll, G., B. LotfizadehDehkordi, and Wang, Q., 2015, “Correlation of Polysiloxane Molecular Structure to Shear-Thinning Power-Law Exponent using Elastohydrodynamic Film Thickness Measurements,” Journal of Tribology, Vol. 137 / 031503-1
  3. Zolper, T., He, Y., Delferro, M., Shiller, P., Doll, G., LotfizadeDehkordi, B., Ren, N., Lockwood, F., Marks, T. J., Chung, Y. W., Greco, A., Erdmemir, A., and Wang, Q., 2016, “Investigation of Shear-Thinning Behavior on Film Thickness and Friction Coefficient of Polyalphaolefin Base Fluids with Varying Olefin Copolymer Content,” Journal of Tribology, Vol. 139, 021504.
  4. Liu, P., Lu, J., Yu, H., Ren, N., Lockwood, F., and Wang, Q., 2017, “Lubricant Shear Thinning Behavior Correlated with Variation of Radius of Gyration via Molecular Dynamics Simulations,” Journal of Chemical Physics, Vol. 147(8):084904. doi: 10.1063/1.4986552. https://www.ncbi.nlm.nih.gov/pubmed/28863549.
  5. Lu, J., Wang, Q., Ren, N., and Lockwood, F., 2019, “Correlation between Pressure-Viscosity Coefficient and Traction Coefficient of the Base Stocks in Traction lubricants: A Molecular Dynamic Approach,” Tribology International, Vol. 134, pp, 328–334. https://doi.org/10.1016/j.triboint.2019.02.013.
  6. Ahmed, J., Shi, J., Lu, J, Ren, N., Lockwood, F., and Wang, Q., 2021, “A Novel Method for Fluid Pour-Point Prediction by Molecular Dynamics Simulations,” Tribology Transactions, http://dx.doi.org/10.1080/10402004.2021.1910391.
  7. Stammer, A., Jungk, M., Stoegbauer, H., Chung, Y. W., Marks, T. J., Wang, Q., and Zolper, T. J., granted 2015, Method of Reducing Friction and Wear between Surfaces under a High Load Condition, US Patent No. 9, 896, 640 B2.
  8. Stammer, A., Jungk, M., Stoegbauer, H., Chung, Y. W., Marks, T. J., Wang, Q., and Zolper, T. J., granted 2015, Energy Efficient, Temporary Shear Thinning Siloxane Lubricants and Method of Using, US Patent No. 9,765,278 B2.
Lubricant Design and Innovation
Lubrication Design and Innovation

Lubrication Design and Innovation

In contrary to textures at micron scales, lubrication design is for the profiles of component surfaces working under full-film or mixed lubrication.  The design is aimed at enhancing hydrodynamics, to be evaluated for load capacity, film thickness, friction (power loss), and leakage, some are conflict metrics. Large amount of computation and design optimization have been conducted to obtain the best design with all positive impact. 

Related Publications

  1. Gu, T., Wang, Q., Gangopadhyay, A., and Liu, Z., 2020, “Journal Bearing Surface Topography Design Based on Transient Lubrication Analysis,” Journal of Tribology. DOI: 10.1115/1.4046289, https://doi.org/10.1115/1.4046289.
  2. Gu, T., Wang, Q., Xiong, S., Liu, Z., Gangopadhyay, A., and Lu, Z., 2019, “Profile Design for Misaligned Journal Bearings Subjected to Transient Mixed-Lubrication,” Journal of Tribology. 141(7): 071701, https://doi.org/10.1115/1.4043506.
  3. Liu, Z., Gu, T., Pickens, D., Nishino, T., and Wang, Q., 2021, “Housing Profile Design for Improved Apex Seal Lubrication Using a Finite-Length Roller EHL Model,” Journal of Tribology, 143 (8), 082301, https://doi.org/10.1115/1.4048998.
  4. Ma, X., Lu, X., Mehta, V. S., and Wang, Q., 2019, “Piston Surface Design to Improve the Lubrication Performance of a Swash Plate Pump,” Tribology International, Vol. 132, pp. 275-28.

AI-Assisted Design and Property Prediction

Professor Wang is among the first to implement AI and data technologies to tribology.  Her group has developed an AI-assisted method for worn surface simulation, which only requires a small number of wear tests, from which worn surfaces are measured at a finite number of time intervals in the wear process. An artificial neural network (ANN) was built and trained with the statistical parameters obtained from the measurements. The trained ANN was then used to predict the wear-dependent statistical parameters for any surfaces in the group. With the original statistical parameters of the unworn surface and their variation due to wear predicted by ANN, the simulation process can generate the corresponding 3-D worn surface with respect to a desired duration within the wear process.

Her group has also developed a data-driven optimization approach for engine-bearing surface design. The data driven approach constructed the bearing design space, and the Pareto optimization and sensitivity analysis methods helped analyze the data and provide insight to the design. The most influential parameter for the optimal bearing surface design for energy-efficient lubrication performance was identified and the optimized design was achieved.  This work has assisted Ford engineers in a new product development and resulted in a software package for their R&D.  

Related Publications

Ao, Y., Wang, Q., and Chen, P., 2002, “Simulating the Worn Surface in a Wear Process,” Wear, 252, pp.37-47. https://doi.org/10.1016/S0043-1648(01)00841-9.

Liu, P., Yu, H., Ren, N., Lockwood, F. E., and Wang, Q., 2015, “Pressure-Viscosity Coefficient of Hydrocarbon Base Oil through Molecular Dynamics Simulations,” Tribology Letters, Vol. 65, paper 34. http://link.springer.com/article/10.1007%2Fs11249-015-0610-6.

Lu, J., Wang, Q., Ren, N., and Lockwood, F., 2019, “Correlation between Pressure-Viscosity Coefficient and Traction Coefficient of the Base Stocks in Traction lubricants: A Molecular Dynamic Approach,” Tribology International, Vol. 134, pp, 328–334. https://doi.org/10.1016/j.triboint.2019.02.013.

Gu, T., Wang, Q., Gangopadhyay, A., and Liu, Z., 2020, “Journal Bearing Surface Topography Design Based on Transient Lubrication Analysis,” Journal of Tribology. DOI: 1115/1.4046289, https://doi.org/10.1115/1.4046289.

Ahmed, J., Shi, J., Lu, J, Ren, N., Lockwood, F., and Wang, Q., 2021, “A Novel Method for Fluid Pour-Point Prediction by Molecular Dynamics Simulations,” Tribology Transactions, Vol. 64, 4, pp. 721-729,  http://dx.doi.org/10.1080/10402004.2021.1910391.

AI-Assisted Design and Property Prediction
Novel Additives and Tribochemically Formed Surface protections

Novel Additives and Tribochemically Formed Surface protections

This is a group of collaborative works on novel S and P free additives, including alkyl-cyclens as friction modifiers, PAO-PiDMA di-block copolymers as viscosity modifiers, crumpled graphene as solid additives, and cycloalkane‑carboxylic acids, organo-MoS2 precursor, organo-silver precursors for in-situ protective low-friction layers. Molecular dynamics simulations, tribochemical kinetics analyses, tribotests, surface topographic evaluations, and surface material inspections were used to investigate the performances of these additives and results surface protection. 

Related Publications and Patents

  1. McCain, M., He, B., Sanati, J., Wang, Q., and Marks, T., 2008, “Aerosol-Assisted Chemical Vapor Deposition of Lubricating MoS2 Films. Ferrous Substrates and Titanium Film Doping” Chemistry of Materials, Vol. 20, pp 5438-5443.
  2. Twist, C., Sevam, A., Chen, L., Kim, M., Weberski Jr. M. P., Ren, N., Marks, T., J., Chung, Y-W, and Wang, Q., 2012, “Molecularly-Engineered Lubricants: Synthesis, Activation, and Tribological Characterization of Silver Complexes as Lubricant Additives,” Advanced Engineering Materials, DOI: 10.1002/adem.201100193, 14, No. 1-2, pp. 101-105.
  3. Twist, C., Bassanetti, I., Snow, M., Delferro, M., Chung, Y. W., Bassi, H., Marchio, L., Marks, T., J., and Wang, Q., 2013, “Silver-Organic Oil Additive for High Temperature Applications,” Tribology Letters, 10.1007/s11249-013-0211-1. Vol. 52, pp. 261–260. http://link.springer.com/article/10.1007/s11249-013-0211-1?no-access=true.
  4. Dou, X., Koltonow, A. R., He, X., Jang, H. D., Wang, Q., Chung, Y.-W., and Huang, J., 2016, “Self-dispersed Crumpled Graphene Balls in Oil for Friction and Wear Reduction,” Proceedings of the National Academy of Science of the United States of America, doi: 10.1073/pnas.1520994113. Vol. 13, pp. 1528–1533. Cover article. www.pnas.org/cgi/doi/10.1073/pnas.1520994113
  5. Desanker, M., Johnson, B., Seyam, A., Chung, Y.-W., Bazzi, H., Delferro, M, Marks, T., and Wang, Q., 2016, “Oil-Soluble Silver-Organic Molecule for in-situ Deposition of Lubricious Metallic Silver at High Temperatures,” ACS Applied Materials & Interfaces, 8(21), pp. 13637–13645, DOI: 10.1021/acsami.6b01597. http://pubs.acs.org/doi/pdf/10.1021/acsami.6b01597
  6. Desanker, M., He, X., Lu, J., Liu, P., Pickens, D., Delferro, M., Marks, J. T., Chung, Y.-W., and Wang, Q., 2017, “Alkyl-Cyclens as Effective Sulfur- and Phosphorus-Free Friction Modifiers for Boundary Lubrication,” ACS Applied Materials and Interfaces, Vol. 9 (10), pp 9118–9125. http://pubs.acs.org/doi/abs/10.1021/acsami.6b15608.
  7. Johnson, B., Wu, H., Desanker, M., Pickens, D., Chung, Y.W., and Wang, Q., 2018, “Direct Formation of Lubricious and Wear-Protective Carbon Films from Phosphorus- and Sulfur-Free Oil-Soluble Additives,” Tribology Letters, Vol. 66: 2. https://link.springer.com/article/10.1007/s11249-017-0945-2.
  8. Desanker, M., He, X., Lu, J., Johnson, B. A., Liu, L., Delferro, M, Ren N., Lockwood, F., Greco, A., Erdemir A., Marks, T. J., Wang, Q., and Chung, Y.-W., 2018, “High-Performance Heterocyclic Friction Modifiers for Boundary Lubrication” Tribology Letters, 60:50, https://link.springer.com/article/10.1007/s11249-018-0996-z.
  9. Wu, H., Khan, A. M., Johnson, B., Sasikumar, K., Chung, Y-W., and Wang, Q., 2019, “Formation and Nature of Carbon-Containing Tribofilms,” ACS Applied Materials & Interfaces, Vol. 11 (17), pp. 16139-16146, https://pubs.acs.org/doi/10.1021/acsami.8b22496
  10. Khan, A. M., Wu, H., Ma, Q., Chung, Y. W., and Wang Q., 2020, “Relating Tribological Performance and Tribofilm Formation to the Adsorption Strength of Surface-Active Precursors,” Tribology Letters, Vol. 68, Article No. 6, https://doi.org/10.1007/s11249-019-1249-5
  11. Ma, Q., Khan, A., Wang, Q., and Chung, Y. W., 2020, “Dependence of Tribological Performance and Tribopolymerization on the Surface Binding Strength of Selected Cycloalkane-Carboxylic Acid Additives,” Tribology Letters. Vol. 68, paper 68, https://doi.org/10.1007/s11249-020-01329-2.
  12. Chung, Y. W., Wang, Q., Ma, Q., and Khan, A., Lubricant Compositions, and Synthesizing Method and Applications of the Same.  In process. Provisional application, May 2020; Full application, No. 17/228,920 May 2021.
  13. Marks, T. J., Gao, Y, Lohr, T., Pickens, D., Wang, Q., and Chung, Y. W., Highly Branched, Low Molecular Weight Polyolefins and Methods for Their Production. PCT/US2019/016762, Application No. 16/963,731. Granted 2022, US Patent 11,242,421.
  14. Chung, Y. W., Johnson, B, and Wang, Q., Granted August 18, 2020, Lubricant Additives, Lubricant Compositions, and Applications of Same. Applied 7/25, 2019, US Patent No. 10,745,637 B2 (Compositions)
  15. Chung, Y. W., Johnson, B, and Wang, Q., Granted September 17, 2019, Lubricant Additives, Lubricant Compositions, and Applications of Same, US Patent No. 10,414,997 B2 (methods)
  16. Marks, T. J., Wang, Q., Chung, Y. W., Delferro, M., Desanker, M., He, X., Granted 2018, Cyclen Friction Modifier for Boundary Lubrication, US Patent 10,081,776, B2.
  17. Huang, J. X., Wang, Q., Chung, Y. W., and Du, X., granted 2018, Crumpled Graphene Balls as Lubricant Additive for Friction and Wear Reduction, US Patent No. 10,138,439.
  18. Marks, T. J., Delferro, M., Wang, Q., Chung, Y. W., Bazzi, H. S., Seyam, A.B., Desanker, M., Johnson, B., Jin, D., Lubricant Additives, Applied 2016,15/013,878, granted 2017, US Patent No. 9,777,021 B2.

Novel Measurement Methods

The paper, “Pressure-Driven Interface Evolution in Solid State Lithium Metal Batteries,” Cell Reports Physical Science, Vol. 1 (2), 100012, by Professor Wang and Collaborators, suggested a method to measure the yield strength of a thin film metal via electrical potential measurement, without doing indentation tests, which inevitably involves the effect of substrate deformation, although Professor Wang and Dr. Liu has developed  an interactive testing-calculation method to eliminate the substrate effect. On the other hand, the recent paper ,  “A unified analogy-based computation methodology from elasticity to electromagnetic-chemical-thermal fields and a concept of multifield sensing,” ASME Open Journal of Engineering, Inaugural issue, introduced a concept of multifield sensing, i. e., to measure the surface elastic field via temperature monitoring, or sense the thermal field via surface normal displacement monitoring at one location, or certain locations, by means of the analogy methodology and the surface-value equivalence. These are newly proposed, awaiting for further exploration. 

Related Publications and Patents

  1. Zhang, X., Wang, Q., Harrison, K. L., Roberts, S. A, and Harris, S. J., 2020, “Pressure-Driven Interface Evolution in Solid State Lithium Metal Batteries,” Cell Reports Physical Science, Vol. 1 (2), 100012, https://doi.org/10.1016/j.xcrp.2019.100012.
  2. Zhang, X. and Wang, Q., 2022, “A unified analogy-based computation methodology from elasticity to electromagnetic-chemical-thermal fields and a concept of multifield sensing,” ASME Open Journal of Engineering, invited, Inaugural issue. https://doi.org/10.1115/1.4053910.
  3. Liu, S. and Wang, Q, 2007, “Determination of Young’s Modulus and Poisson’s Ratio for Coatings,” Surface and Coatings Technology, Vol. 201, pp. 6470-6477.
  4. Wang, Q. and Zhang, X., Multifield, Multifunctional Sensors, in process; Provisional application, No.: 63/296,558, January 5, 2022.
  5. Liu, S. and Wang, Q., granted 2007, Determination of Young’s modulus and Poisson’s ratio of coatings, US Patent No. 7,165,463.
Novel Measurement Methods
Isothermal Bearings with Heat-Pipe Cooling

Isothermal Bearings with Heat-Pipe Cooling

Heat-pipe cooling can efficiently dissipate heat away from where it is generate. An isothermal journal bearing has been developed by incorporating the heat-pipe-cooling technology; it consists of an inner ring, an outer ring, and several circumferential grooves machined on one of the rings, with an amount of working fluid  charged into the grooves.  The results indicate that the heat pipes integrated with the bearing can spread frictional heat rapidly along the bearing circumference, resulting in a uniform temperature distribution in the bearing with a low peak temperature and stable transient thermal performance.  The trend of temperature variations and the evidence of surface changes suggest that the temperature control provided by the heat-pipe cooling depresses the interfacial temperature and reduces the tendency of asperity adhesion. The same technology was also applied to an innovative design of engine pistons. 

Related Publications and Patents

  1. Wang, Q., Chen, G., and Cao, Y., 1999, “Analyses of Heat-pipe Cooled Isothermal Journal Bearing,” ASME Journal of Tribology, Vol. 121, pp. 546-552.
  2. Chen, G., Tso, C., Wang, Q., and Cao, Y., 1999, “Development of an Isothermal Journal Bearing Employing Heat-Pipe Cooling Technology,” Tribology Transactions, Vol. 42, 401-406.
  3. Wang, Q. and Cao, Y.,  Isothermal Journal Bearing. Granted 2001, US Patent No. 6210042.
  4. Cao, Y. and Wang, Q.,  Engine Piston, Granted 2001, US Patent No. 5454351