98 0

Mechanical properties of Mo-Nb-Si-B quaternary alloy fabricated by powder metallurgical method

Title
Mechanical properties of Mo-Nb-Si-B quaternary alloy fabricated by powder metallurgical method
Author
김영도
Keywords
Mo-Si-B alloy; Niobium; Pressureless sintering; Vickers hardness; Fracture toughness
Issue Date
2017-06
Publisher
ELSEVIER SCI LTD
Citation
INTERNATIONAL JOURNAL OF REFRACTORY METALS & HARD MATERIALS, v. 65, page. 14-18
Abstract
Mo-Si-B alloys composed of two intermetallic compound phases (Mo5SiB2 and Mo3Si) and a molybdenum solid solution matrix phase have been investigated for use as high-temperature structural materials due to their high melting point and good creep resistance. However, despite these advantages, Mo-Si-B alloys are difficult to use in practical applications because they have insufficient fracture toughness at room temperature. So, in many researches, microstructure control and the addition of other elements in the alpha-Mo matrix phase are conducted as an effective way to improve the fracture toughness.In this study, niobium (Nb) was added to a Mo-Si-B alloy by a powder metallurgical method to improve the mechanical properties. First, the Mo and Nb powders were pulverized by high-energy ball milling. Then, the synthesized intermetallic compound powders, which were fabricated by continuous heat treatment under a H-2 atmosphere, were mixed with ball-milled Mo and Nb powder. Pressureless sintering was conducted at 1400 degrees C for 3 h under a H-2 atmosphere. The Vickers hardness and fracture toughness were measured to investigate the mechanical properties of the sintered Mo-Si-B and Mo-Nb-Si-B alloy. The Vickers hardness was about 425 Hv for a Mo-Nb-Si-B alloy, which was lower value of 165 Hv compared to Mo-Si-B alloy (590 Hv). On the other hand, the fracture toughness of the Mo-Nb-Si-B alloy (14.5 MPa center dot root m) greatly increased compared to that of the Mo-Si-B alloy (12.6 MPa center dot root m). (C) 2016 Elsevier Ltd. All rights reserved.
URI
https://www.sciencedirect.com/science/article/abs/pii/S0263436816303791?via%3Dihubhttps://repository.hanyang.ac.kr/handle/20.500.11754/114544
ISSN
0263-4368
DOI
10.1016/j.ijrmhm.2016.10.008
Appears in Collections:
COLLEGE OF ENGINEERING[S](공과대학) > MATERIALS SCIENCE AND ENGINEERING(신소재공학부) > Articles
Files in This Item:
There are no files associated with this item.
Export
RIS (EndNote)
XLS (Excel)
XML


qrcode

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.

BROWSE