Development of Technology of Robotized Laser Welding of Thin Wall Products from Heat-Resistant Alloys

Results of the developed industrial technology of restoration of a surface corrosion-resistant staly are presented by method of laser building up. The comparative analysis of a microstructure of the built-up wearproof layer, an alloyage zone with material of a basis and diffusive zone at the different technological modes of building up is given. Influence of morphology of particles of additive powder on parametrical characteristics of the roller received by laser gas powder building up is investigated. The optimum modes of building up on a substrate from steel 12Cr18Ni10Ti are set. Tests for firmness against intercrystalline corrosion of the built-up powder compositions are executed by the AM method. Metalgraphic assessment of corrosion resistance is presented.

Influence of Nanopowders on Corrosion Resistance of Welded Joints

The paper presents experimental results on influence of tungsten, molybdenum nanopowders and aluminum oxyhydroxide phase introduced into the molten pool on the corrosion resistance of welded joints. It was shown that the nature of nanopowders significantly impacts intercrystalline corrosion of the welding joint.

Zirconia Modified Aluminide Coatings Deposited by VPA and CVD Methods

The article presents the experimental trial to connect aluminizing methods: VPA and CVD. Inconel 713 alloy was used as the base material. The purpose of the process was to obtain a layer modified with more Zr than the coatings deposited by CVD. The conducted tests revealed intercrystalline corrosion in the area of β-NiAl phase granules, which indicates that precise selection of processing conditions is the key factor for Zr-modified aluminizing. The resultant microstructural faults of the layer, however, didn’t impair the properties PS-PVD-deposited ceramic layer. The zirconium content in the outer zone equalled 2-3 at.%. in the second variety of the process. In future the described coating may form an alternative for Pt-modified aluminide coatings.