Effect of Mutual Positions of Individual Contacts on the Overall Resistance and Elastic stiffness of a Cluster of Contacts

International Journal of Fracture Mechanics - Tập 160 - Trang 101-108 - 2009
John Ervin1, Igor Sevostianov1
1Department of Mechanical Engineering, New Mexico State University, Las Cruces, USA

Tóm tắt

The paper provides statistical analysis on the effect of mutual positions of individual contacts on the overall resistance and incremental elastic stiffness of a cluster of contacts. We consider an example of a cluster with 76 contact spots of the same radii. The regular lattice of the contacts is compared with the perturbed ones (random clusters). The constriction resistance is determined as a sum of self resistance of the individual contacts and interactions between them. It is shown that the effect of perturbations is very small and, therefore, the mean distance between the centers of individual contacts can be used to estimate the overall cluster resistance. Using elasticity-conductivity cross-property connections, this result is transferred to the incremental elastic stiffness of the cluster. Thus, we established a correspondence between cluster of regular structure and cluster of randomly located contacts. The geometrical parameters governing elastic compliance and spreading resistance of the clusters are number of contact spots and the average distance between individual contacts.

Tài liệu tham khảo

Argatov I., Sevostianov I. (2009) On relations between geometries of microcontact clusters and their overall properties. International Journal of Engineering Science 47: 959–973 Barber J.R. (2003) Bounds on the electrical resistance between contacting elastic rough bodies. Proc. R. Soc. Lond. A 459: 53–66 Galin, L.A. (2008) Contact problems: the legacy of L.A.Galin. Ed. G.M.L.Gladwell, Dordrecht, Springer. Gladwell G.M.L., Fabrikant V.I. (1982) The interaction between a system of circular punches on an elastic half-space. J. Appl. Mech., 49: 341–344 Grechka V., Kachanov M. (2006) Effective elasticity of rocks with closely spaced and intersecting cracks. Geophysics 71: D85–D91 Greenwood J.A. (1966) Constriction resistance and the real area of contact. Brit. J. Appl. Phys 17: 1621–1622 Holm R. (1929) Uber metallische Kontaktwiderstände. Wissenschaftliche Veröeffentlichungen aus den Siemens- Werken 7: 217–258 Kachanov M., Montagut E. (1989) A simple analysis of intersecting cracks and cracks intersecting a hole. International Journal of Fracture 40: R61–R65 Sevostianov I., Kachanov M. (2004) Connection between elastic and conductive properties of microstructures with Hertzian contacts. Proceedings of the Royal Society of London (A) 460: 1529–1534 Sevostianov, I. and Kachanov, M. (2008) Connection between elastic and conductive properties of heterogeneous materials, Advances in Applied Mechanics, 42, ed. by van der Giessen and H. Aref, Elsevier. Sevostianov I., Kachanov M. (2009) Elasticity- conductivity connections for contacting rough surfaces: an overview. Mechanics of Materials 41: 375–384 Sevostianov I., Kachanov M. (2009) Incremental compliance and resistance of contacts and contact clusters: implications of the cross-property connection. International Journal of Engineering Science 47: 974–989 Singer, M.T. Kshonze, K. (1991) Electrical resistance of random rough contacting surfaces using fractal surface modeling. In: Proceedings of the Thirty-Seventh IEEE Holm Conference on Electrical Contacts, 1991., Chicago, IL, USA.