Analysis of material transfer from a soft workpiece to a hard tool, Part I - Lump growth model

An important mechanism reducing the lifetime of the deepdrawing tools is material transfer from the workpiece to the tool, resulting in the buildup of lumps on the tool surface. In this study, a lump growth model, based on transfer mechanisms observed in experiments, is developed. The development of the summit height distribution of the tool surface is calculated from the growth behavior of the individual lumps. Important parameters influencing material transfer are determined from the calculated summit height distributions. It follows that lump growth can be decreased and, under certain conditions prevented, by a higher (surface) hardness of the workpiece, a lower roughness of the tool surface, a lower nominal contact pressure, and a lower shear strength of the interface. These results are in general agreement with results obtained from experiments. Experimental results are presented in an accompanying paper (de Rooij and Schipper, 2000).

[1]  Tribological aspects of unlubricated deepdrawing processes , 1998 .

[2]  M. Cocks.  Role of Displaced Metal in the Sliding of Flat Metal Surfaces , 1964 .

[3]  R. J. Adler,et al.  A non-gaussian model for random surfaces , 1981, Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences.

[4]  P. Oxley,et al.  An explanation of the different regimes of friction and wear using asperity deformation models , 1979 .

[5]  M. D. Rooij,et al.  Analysis of Material Transfer From a Soft Workpiece to a Hard Tool: Part II-Experimental Verification of the Proposed Lump Growth Model , 2001 .

[6]  J. Greenwood.  A unified theory of surface roughness , 1984, Proceedings of the Royal Society of London. A. Mathematical and Physical Sciences.

[7]  M. Brendlé,et al.  A general approach to discontinuous transfer films: influence of sliding speed and stick-slip phenomena , 1997 .

[8]  Morton Antler,et al.  Processes of metal transfer and wear , 1964 .

[9]  E. Schedin,et al.  Galling mechanisms in lubricated systems: A study of sheet metal forming , 1993 .

[10]  V. Sedláček.  Metallic surfaces, films, and coatings , 1992 .

[11]  J. Halling,et al.  The Elastic—Plastic Contact of Rough Surfaces and its Relevance in the Study of Wear , 1988 .

[12]  John A. Williams,et al.  The prediction of friction and wear when a soft surface slides against a harder rough surface , 1996 .

[13]  D. Landheer,et al.  The mechanism of metal transfer in sliding friction , 1974 .

[14]  K. Hokkirigawa,et al.  An experimental and theoretical investigation of ploughing, cutting and wedge formation during abrasive wear , 1988 .