03.2020.385.393

MICROSTRUCTURE OF THE NICKEL-BASE AGING MARTENSITE ALLOY AFTER SPINNING PROCESS OF THIN TUBE AT DIFFERENT STRAIN REDUCTION

Author(s):
Le Trung Kien1, Nguyen Thai Hoc2, Pham Van Cuong2, Le Thai Hung3*

Affiliation(s):
1School of Mechanical Engineering, Hanoi University of Science and Technology, Hanoi, Vietnam

2Institute of Technology – General Department of Military Industries and Manufacture

3School of Materials Science and Engineering – Hanoi University of Science and Technology

*Corresponding Author Email: hung.lethai@hust.edu.vn

This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Tube spinning is an advanced forming process to produce thin-walled tubular workpieces with high precision and improved mechanical properties, widely used in aviation, chemistry, power industries… In this study, the effects of spinning deformation and subsequent heat treatments on the mechanical properties and microstructure of the nickel-base aging martensite alloy were evaluated comparatively with the perform. Plastic deformation during spinning elongated the grains severely in the direction of metal flow. The solution treatment resulted in a drastically refined grain and recrystallised microstructure, removing the effect of plastic deformation. The results show that with the increase of spinning pass, the fiber microstructure comes into being gradually in axial direction and the circumferential microstructure also stretches obviously along circumferential direction. At the same time, the tensile strength increases in axial direction.