Metallurgical Laboratory, The Dow Chemical Co., Midland, Mich.
Pages: 15 Published: Jan 1958
The standard methyl iodide (CH3I) etch followed by a rinsing schedule designed to remove light magnesium hydroxide (Mg(OH) 2) films formed during the etching process gives film-free surfaces suitable for electron microscope examination on most of the magnesium-aluminum alloys, magnesium-aluminum-manganese alloys, and magnesium alloys containing amounts of aluminum and zinc up to 1 per cent aluminum and 1 per cent zinc. Modifications of this etching and/or rinsing schedule or new etchants are required for the remaining magnesium alloys.
Satisfactory etching techniques are now available for preparing most of the present magnesium alloys for electron microscope studies. Notable exceptions are the alloys containing zinc and zirconium. The elimination of fine zirconium and complex hydride particles which tend to obscure the microstructures of these alloys has not been possible.
Paper ID: STP39537S