Properties and Structure of Nanocrystalline Layers Obtained by Manual Metal Arc Welding (MMA)

Abstract

The present paper is the result of the investigations of the properties and structure of nanocrystalline layers deposited from iron-based nanoalloy on steel S355N substrate by manual metal arc welding method (MMA). In the process of welding a 100 A current intensity was used with desiccation preheating at 80°C while maintaining the interpass temperature at range of 200°C. The resultant deposit welds were subjected to macro and microscopic metallographic examination, X-ray phase analyses and crystallite size was analyzed by X-ray diffractometry (XRD), additionally EDX chemical composition analysis of precipitates during scanning electron microscopy was performed. Working properties of the obtained nanocrystalline deposit welds were evaluated based on hardness and metal-to-mineral abrasive wear. The results of the deposit welds working properties measurements were compared with the properties of wear resistant steel HARDOX 400 type used as the reference material.

Keywords

• nanocrystalline layers
• crystallite size
• manual metal arc welding
• deposit weld