Serbian Tribology Society SERBIATRIB ‘19 16 th International Conference on Tribology Faculty of Engineering University of Kragujevac Kragujevac, Serbia, 15 – 17 May 2019 WEAR RESISTANCE UNDER DRY CONDITIONS OF DIFFERENT FILLER METALS USED FOR HARD FACING Dušan ARSIĆ 1 , Vukić LAZIĆ 1 , Dragan DŽUNIĆ 1 , Srbislav ALEKSANDROVIĆ 1 , Milan ĐORĐEVIĆ 2 , Milan UHRIČIK 3 , Aleksandra ARSIĆ 4 1 Faculty of Engineering, University of Kragujevac, Sestre Janjid 6, 34000 Kragujevac, Serbia. 2 Faculty of Technical Sciences, Knjaza Milosa 7, 28000 Kosovska Mitrovica, Serbia 3 University of Žilina, Faculty of Mechanical Engineering, Univerzitna 8215/1, 010 26 Žilina, Slovakia. 4 Faculty of Mechanical Engineering, Kraljice Marije 16, 11000 Belgrade, Serbia. *Corresponding author: dusan.arsic@fink.rs Abstract: The aim of this paper is to show wear properties of different types of filler metals aimed for hard facing and exploitation in dry condition. Testing of wear resistance is done in laboratory on prepared samples/models in order to simulate real exploitation conditions. Samples were made by hard facing of carbon steel using 4 different filler metals. Hard facing was done by using MMA welding method in three layers with enough height so samples could be made. After samples were made, the hardness and microstructure of all zones of hard facing were determined. Testing of wear resistance is done using block on disc contact on samples made from pure weld metal. As a parameter for estimates of the wear resistance of models it was used volume of worn material in mm 3 . Metallographic investigations and hardness measurements were used as additional parameter for drawing the conclusions. Keywords: Hard facing, filler metals, hardness, microstructure, wear volume. 1. INTRODUCTION Numerous working parts of different technical systems are during the exploitation exposed to various types of complex wear processes. Since never one type of wear is dominant, it is very hard to determine which of the wear mechanisms lead to biggest damages. Usually, damages are consequences of coupled action of several wear mechanisms. That is why it is necessary to apply higher quality materials, which are resistant to wear and which can produce more working hours for the concrete machine part. On the other side, manufacturing of large parts with using of high-quality materials offten is very expensive. Than the problem could be solved by application of hard facing. Hard facing enables reparation of damaged parts or manufacturing of the new parts by depositing the high quality material on the cheaper material. In that way, one saves not only material and money, but also the time needed for revitalizing damaged parts, shortening the downtimes, etc [1]. There is many examples where hard facing was succesifully applied in order to achieve above mentioned goals such as: claddings for deep-hole drilling [2], rotary tiller blades [3], gears [4], mixer blades [5], etc. In this paper, four different types of filler materials were used. These materials are aimed for hard facing of the parts exposed to 16th International Conference on Tribology - SERBIATRIB ‘19 423