| 2014 №03 (01) |
DOI of Article 10.15407/tpwj2014.03.02 |
2014 №03 (03) |
The Paton Welding Journal, 2014, #3, 11-15 pages
STRUCTURE OF SURFACE-MELTED ZONE OF CAST HIGH-NICKEL ALLOY KhN56MBYuDSh AFTER LASER SURFACE TREATMENT
A.A. POLISHKO, V.Ya. SAENKO, A.Yu. TUNIK and S.N. STEPANYUK
E.O. Paton Electric Welding Institute, NASU. 11 Bozhenko Str., 03680, Kiev, Ukraine. E-mail: office@paton.kiev.ua
Abstract
The laser surface treatment influences greatly the structure and service properties of products. The effect of this treatment on high-nickel alloys used in critical structures represents the interest. The effect of laser surface treatment on structure and properties of cast high-nickel alloy KhN56MBYuDSh was evaluated. Presented are the results of investigations of dispersity of dendrtitic structure obtained by the method of electroslag remelting (ESR) of hollow ingot of this alloy and surface-melted zone after its laser surface treatment in the nitrogen and helium atmosphere. It is shown that in the surface-melted zone the distance between the branches of dendrites is by 2 orders smaller than in cast metal in the state after ESR without the laser treatment. The results of durometric investigations are given. It was found that after the laser treatment the characteristics of microhardness are averaged within the whole volume of the melted layer. In addition, the increase in level of microhardness of the melted layer in nitrogen is observed. Generally, the positive effect of this treatment on structure and microhardness of the surface-melted zone was found. 6 Ref., 4 Tables, 8 Figures.
Keywords: laser surface treatment, high-nickel alloy, surface-melted zone, metallographic examinations, dendritic structure, distance between the primary branches of dendrites, distance between the secondary branches of dendrites, durometric investigations, microhardness
Received: 24.12.13
Published: 28.03.14
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