| Abstract Scope |
This study investigates the surface properties and microstructural evolution of powder metallurgy tool steels, ASP 2012 and ASP 2053, after hot dip aluminizing (HDA) using pure aluminum and Al-12%Si alloy. Samples were coated at 700°C for 3 minutes and then diffusion annealed at 800°C for 1 hour. Characterization was conducted via optical microscopy, SEM, EDS, XRD, and microhardness testing.
Results revealed the formation of FeAl, Fe3Al, and FeAl2 intermetallic phases, with Al-12%Si coatings showing improved uniformity and stronger Fe-Al bonding. Hardness significantly increased, especially in Al-12%Si coated and annealed samples. The coating process effectively enhanced surface durability and thermal stability.
HDA combined with diffusion annealing proved to be a cost-effective and efficient surface treatment method for PM tool steels. These findings highlight the suitability of aluminized ASP 2012 and ASP 2053 for demanding tooling and die applications, where high wear and oxidation resistance are essential. |