Analysis of precipitate density of an aluminium alloy by TEM and AFM

• Published in: REM - International Engineering Journal Vol. 69; no. 4; pp. 451 - 457
• Main Authors: Jacumasso, Sheila Cristina, Martins, Juliana de Paula, Carvalho, André Luís Moreira de
• Format: Journal Article
• Language: English
• Published: Fundação Gorceix 01-12-2016
• Subjects: aluminium alloy AA7050; ENGINEERING, MECHANICAL; GEOLOGY; interrupted ageing; MECHANICS; METALLURGY & METALLURGICAL ENGINEERING; secondary precipitation; TEM and AFM; TEM and AFM; interrupted ageing; aluminium alloy AA7050; secondary precipitation
• ISSN: 2448-167X; 2448-167X
• DOI: 10.1590/0370-44672016690019

Abstract The quantification of nanometric precipitates in Al-Zn-Mg-Cu alloys has been performed by a series of experimental techniques. Especially in the AA7050 alloy, after ageing heat treatment, the particles responsible for the hardening become very thin. Typically, these precipitates of nanometric sizes are mainly characterized by transmission electron microscopy (TEM), which in this particular case, requires a very meticulous preparation. This study investigated a possible alternative quantification of the precipitates by atomic force microscopy (AFM) to complement the technique by TEM. For this, three conditions for heat treatment of an aged aluminium alloy AA7050 were therefore chosen to produce different density and sizes of precipitates. The experimental results showed that the AFM technique proved to be a valid qualitative tool and may complement the results obtained by TEM an exploratory analysis for the microstructures.