Formation of Al‐enriched surface layers through reaction at the Mg‐substrate/Al‐powder interface

Abstract

Al‐enriched surface layers containing a Mg17Al12 intermetallic phase and a solid solution of Al in Mg were fabricated by heating Mg specimens in contact with Al powder in a vacuum furnace. The layer formation process proceeded through partial melting at the Mg‐substrate/Al‐powder interface. The test results suggest that a good contact between the Al powder and the Mg substrate is required during heat treatment. In this study, a pressure of 1 MPa was applied to improve the contact of the Al powder with the Mg specimen. When the powder was pressed down during heating, it was possible to reduce the process temperature from 450 °C to 440 °C. The layers produced at 440 °C in a short heating time (40 min) were thick, continuous and uniform. The microhardness of the Al‐enriched layers was much higher than that of the Mg substrate. The results of the electrochemical corrosion tests indicated that the Mg specimens with an Al‐enriched surface layer had better corrosion resistance than the bare Mg. Copyright © 2014 John Wiley & Sons, Ltd.

Vibro-abrasive machining as a deburring and surfaces finishing process of casing make with aluminum alloy EN AW-2017A

“…Próbki wykonano ze stopu aluminium EN AW-2017A (AlCuMg1, PA6) jako materiału często stosowanego do produkcji elementów konstrukcyjnych samolotów, części maszyn, sprzętu wojskowego, podzespołów dla przemysłu motoryzacyjnego [8]. Stopy te cechują się dobrym przewodnictwem cieplnym i elektrycznym.…”

Characterization of the Surface Layer of Mg Enriched with Al and Si by Thermochemical Treatment

“…The solid medium is generally in the form of the metal powder, e.g. Al [3][4][5][6][7], Al+Zn [7][8][9][10][11], Zn+Al [12], Sb+Zn [13] or Zn+Y [14]. Layers fabricated on Mg or an Mg alloy using pure Al powder contained Mg-Al intermetallic phases.…”

“…The heat treatment of an AZ91D alloy substrate in contact with Zn+Y powder resulted in the formation of a surface layer containing a large amount of an Mg 5 Al 2 Zn 2 intermetallic phase. The experimental results presented in [6,7,11,12] show that the key factor affecting the formation of alloyed layers on Mg through thermochemical treatment was good contact between the source of diffusion elements and the substrate material. Adequate contact facilitated the diffusion of alloying elements from the outside source to the Mg-based substrate.…”

Formation of Al-alloyed Layer on Magnesium with Use of Casting Techniques

“…Al-enriched layers can be produced using various methods, e.g. laser surface alloying/cladding [3][4][5], diffusion treatment in molten salts [6,7], diffusion aluminizing treatment [8][9][10][11][12][13][14][15], PVD combined with annealing [16][17], cold spray with subsequent heat treatment [18,19], welding [20], and electrodeposition [21]. The findings reported in the above works suggest that it is the Mg-Al intermetallic phases forming in the microstructure of Al-enriched layers that are responsible for an increase in the hardness as well as corrosion and wear resistance of magnesium and magnesium alloy products.…”