Original scientific paper

Analyses of the reasons for the decreased service time of CrN-coated die for aluminy hot extrusion – a case study

P. Fajfar ; University of Ljubljana, Faculty of Natural Sciences and Engineering, Ljubljana, Slovenia
P. Panjan ; Jožef Stefan Institute, Ljubljana, Slovenia
M. Terčelj ; University of Ljubljana, Faculty of Natural Sciences and Engineering, Ljubljana, Slovenia
G. Kugler ; University of Ljubljana, Faculty of Natural Sciences and Engineering, Ljubljana, Slovenia

Abstract

Presented study shows that considerable reserves still exist for increasing the service times (lifetimes) of CrN – coated dies for Al hot extrusion. The main reasons for the decreased service times are revealed and explained regarding the selected CrN - coated die for hot extrusion, i.e. why the service time of the coated-die is not in accordance with the wear resistance of the CrN - coating. The shaping of the bearing surface and presence of the scratches, size and amount of nonmetalic inclusions in the die steel, nodular defects in the CrN - coating, as well as thicknesses uniformity of CrN - coatings along the bearing surface, are relevant influential parameters.

Keywords

CrN - coated; demage; Al hot extrusion; physcial vapor deposition coating; die wear; service time

Hrčak ID:

153622

URI

https://hrcak.srce.hr/153622

Publication date:

1.7.2016.

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