**Łukasz Konat**

Department of Materials Science, Welding and Strength of Materials, Wrocław University of Science and Technology, 50-370 Wrocław, Poland; lukasz.konat@pwr.edu.pl

Received: 17 July 2019; Accepted: 18 August 2019; Published: 21 August 2019

**Abstract:** The paper presents structure and mechanical properties of welded joints of the high-strength, abrasive-wear resistant steel Hardox Extreme. It was shown that, as a result of welding this steel, structures conducive to lowering its abrasion-wear resistance are created in the heat-affected zone. Width of the zone exceeds 60 mm, which results in accelerated wear in the planned applications. On the grounds of the carried-out examinations of structures and selected mechanical properties, a welding technology followed by heat treatment of heat-affected zones was suggested, leading to reconstruction of *HAZ* structures that is morphologically close to the base material structure. In spite of high carbon equivalent (*CEV*) of Hardox Extreme, the executed welding processes and heat treatment did not result in the appearance, in laboratory conditions, of welding imperfections in the welded joints.

**Keywords:** wear-resistant martensitic steel; submerged arc welding (SAW); heat treatment; structures; hardness changes; mechanical properties; Hardox Extreme steel
