Abstract
In order to reduce the intermetallic compounds formed during the application of an Al–7Ni wt % hot-dip multifunctional coating on boron steel, developed for Tailor Welded Blanks (TWB) and hot stamping, 2–6 wt % Si was added to the coating to change the reaction layer. The coating was run at 690 °C for 120 s. Al9FeNi phases were formed on the steel interface, Fe2Al5 was formed on the steel, FeAl3 was generated between the existing layers, and flake-type Al2Fe3Si3 was formed in the Fe2Al5 phase, depending on the Si content. In addition, as Si was added to the coating, the thickness of the Fe2Al5 phase decreased and the thickness of the Al9FeNi phase and Al2Fe3Si3 increased. The decrease in the thickness of the Fe2Al5 phase was mainly due to the effect of the Si solid solution and the Al2Fe3Si3 formation in the Fe2Al5 phase. The reason for the growth of Al9FeNi is that the higher the Si content in the coating, the more the erosion of the interface of the steel material due to the coating solution. Therefore, the outflow of Fe into the coating liquid increased.
Highlights
In recent years, automobile manufacturers have applied Tailor Welded Blanks (TWB) and hot-stamping, which combines Al–Si coated high strength boron steel and low strength steel or thinner thickness boron steel using a laser to achieve more light-weight structures and increased collision stability [1,2,3,4,5]
In the TWB and hot-stamping process of Al–Si coated boron steel, problems arise because fracture occurs in the FeAl intermetallic compound (IMC) and the ferrite generated due to dissolution of the Al–Si coating layer near the melting boundary
Al–Ni coating, which is known to have a higher oxidation resistance at high temperatures compared to Al coating [11], and an appropriate amount of austenite stabilizing element is added to the coating to prevent ferrite and Fe–Al-type IMC formation
Summary
Automobile manufacturers have applied Tailor Welded Blanks (TWB) and hot-stamping, which combines Al–Si coated high strength boron steel and low strength steel or thinner thickness boron steel using a laser to achieve more light-weight structures and increased collision stability [1,2,3,4,5]. In the TWB and hot-stamping process of Al–Si coated boron steel, problems arise because fracture occurs in the FeAl intermetallic compound (IMC) and the ferrite generated due to dissolution of the Al–Si coating layer near the melting boundary. This causes the tensile strength and the collision characteristics to degrade [6,7,8,9]. We investigate whether the effect of reducing the η phase due to Si addition occurs, and what causes this phenomenon
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
