Special features of heat affected zone (HAZ) formation in multipass non-vacuum electron beam deposition

Abstract

The microstructures of HAZ formed in multipass non-vacuum electron beam deposition from a 10R6M5 steel powder mixture. It has been established that microstructural evolution of HAZ as depended on the number of electron beam passes can be described as follows: martensite/beinite/ferrite structures, ferrite/pearlite mixed structures with coarse grain boundary and fine intra-grain pearlite grains, and ferrite/pearlite structures similar to those of the base metal formed after, 1, 2, and 3 passes, respectively. Extra alloying the powder mixture with tungsten carbide resulted in reduced heating in HAZ during both second and third deposition passes so that the above-described refined ferrite/pearlite structures with two pearlite types has been formed only after the third pass.

Keywords:

• Non-vacuum electron beam deposition
• 10R6M5 steel
• 20 steel
• heat-affected zone
• microstructure
• microhardness

Acknowledgements

The original work was carried out within the framework of the preferred direction of TPU evolvement ‘Nanotechnologies and beam-plasma technologies for creating materials with desired properties’.