Observations of intermetallic compound formation of hot dip aluminized steel
Research output: Chapter in Book/Report/Conference proceeding › Conference contribution
Authors
Colleges, School and Institutes
External organisations
- Material Science and Engineering
- SEOUL NATIONAL UNIVERSITY INDUSTRY - ACADEMIC COOPERATION FOUNDATION
- University of Antwerp
Abstract
A hot dip aluminizing process to simulate the continuous galvanizing line (CGL) was carried out in three successive steps by a hot dip simulator: the pre-treatment for removing scales on the 200 × 250 mm2 and 1mm in thickness cold rolled steel sheet, the dipping in 660°C Al-Si melt for 3s and the cooling. In a pre-treatment, the steel specimen was partly coated by Au to confirm the mechanism of intermetallic compound (IMC) formation. Scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), and transmission electron microscopy (TEM) analyses were followed to observe the cross-section and the distribution of the elements. The specimen was analyzed in the boundary of the dipped-undipped part to see the formation mechanism of the aluminized steel. An intermetallic compound (IMC) is rapidly developed and grown in the steel-liquid interface. It has been usually reported that the IMC was formed by the dissolution of iron in the steel substrate toward the melt and the diffusion of aluminum in an opposite direction. The specimen is covered with aluminum-10 wt.% silicon, forms the IMC in the part that was not Au coated. However, IMC is not formed in the Au-coated part. The interface of the dipped-undipped is also analyzed by EDX. At the interface of the steel-IMC, it is clearly shown that the IMC is only formed in the dipped part and exists in the steel substrate as well, and contributes by iron, aluminum and silicon. The result clearly shows that only aluminum diffuses into the steel substrate without the dissolution of iron and forms the IMC between the steel substrate and the melt. Au coating and the short dipping time prevent the iron from dissolving into the aluminum melt. By TEM combined with focused ion beam (FIB) sample preparation, the IMC is confirmed as Fe2SiAlg, a hexagonal structure with space group P63/mmc.
Details
Original language | English |
---|---|
Title of host publication | Aluminium Alloys 2006 |
Subtitle of host publication | Research Through Innovation and Technology - Proceedings of the 10th International Conference on Aluminium Alloys |
Publication status | Published - 2006 |
Event | 10th International Conference on Aluminium Alloys, (ICAA-10) - Vancouver, Canada Duration: 9 Jul 2006 → 13 Jul 2006 |
Publication series
Name | Materials Science Forum |
---|---|
Number | PART 2 |
Volume | 519-521 |
ISSN (Print) | 0255-5476 |
ISSN (Electronic) | 1662-9752 |
Conference
Conference | 10th International Conference on Aluminium Alloys, (ICAA-10) |
---|---|
Country | Canada |
City | Vancouver |
Period | 9/07/06 → 13/07/06 |
Keywords
- Diffusion, Dissolution, Hot dip aluminizing process, Interface, Intermetallic compound