Aviometal Spa

Arsago Seprio, Italy

Aviometal Spa

Arsago Seprio, Italy
SEARCH FILTERS
Time filter
Source Type

Gerosa R.,Polytechnic of Milan | Rivolta B.,Polytechnic of Milan | Derudi U.,Aviometal Spa
ASTM Special Technical Publication | Year: 2010

The microstructural modifications occurring during the natural or artificial aging of the aluminum alloys are related to modifications of physical properties such as electrical conductivity, hardness, and volume, each of them measured by specific instruments. In this paper the dimensional changes during the aging time were investigated through a high precision dilatometer; this technique keeps the sample at constant temperature and follows the precipitation phenomena versus time continuously. All the samples were taken from commercial thick plates of different aluminum alloys. The heavy plastic deformation during rolling was responsible for introducing anisotropy into the plate, so that the samples for the investigation were taken in the longitudinal, long transverse, and short transverse directions. By analyzing the dimensional changes of the samples versus aging time, standard and non-standard time-temperature values were selected as aging parameters for samples designated for mechanical and intergranular corrosion tests. The results obtained showed that the dilatometer can give important information about the precipitation kinetics occurring during aging, and it can be considered a useful instrumentation for the optimization of aging of aluminum alloys. Copyright © 2009 by ASTM International.


Silva G.,Polytechnic of Milan | Rivolta B.,Polytechnic of Milan | Gerosa R.,Polytechnic of Milan | Derudi U.,Aviometal Spa
Journal of Materials Engineering and Performance | Year: 2013

For the past many years, 7075 aluminum alloys have been widely used especially in those applications for which high mechanical performances are required. It is well known that the alloy in the T6 condition is characterized by the highest ultimate and yield strengths, but, at the same time, by poor stress corrosion cracking (SCC) resistance. For this reason, in the aeronautic applications, new heat treatments have been introduced to produce T7X conditions, which are characterized by lower mechanical strength, but very good SCC behavior, when compared with the T6 condition. The aim of this study is to study the tensile properties and the SCC behavior of 7075 thick plates when submitted to a single-step aging by varying the aging times. The tests were carried out according to the standards and the data obtained from the SCC tests were analyzed quantitatively using an image analysis software. The results show that, when compared with the T7X conditions, the single-step aging performed in the laboratory can produce acceptable tensile and SCC properties. © 2012 ASM International.


Silva G.,Polytechnic of Milan | Rivolta B.,Polytechnic of Milan | Gerosa R.,Polytechnic of Milan | Derudi U.,Aviometal Spa
Metallurgia Italiana | Year: 2012

For many years 7075 Aluminum alloys have been widely used especially in those applications for which high mechanical performances are required. It is well known that the alloy in the T6 condition is characterized by the highest ultimate and yield strengths, but, at the same time, by poor stress corrosion cracking (SCC) resistance. For this reason, in the aeronautic applications, new heat treatments have been introduced to produce T7X conditions, which are characterized by lower mechanical strength, but very good SCC behavior, when compared with the T6condition. The aim of this work is to study the tensile properties and the SCC behavior of 7075 thick plates when submitted to a single step ageing by varying the ageing times. The tests were carried out according to the standards and the data obtained from the SCC tests were analyzed quantitatively by an image analysis software. The results show that, if compared with the T7X conditions, the single step ageing performed in the laboratory can produce acceptable tensile and SCC properties. The data should be confirmed by experiments carried out on thick plates submitted to heat treatments in industrial furnaces.


Gerosa R.,Polytechnic of Milan | Rivolta B.,Polytechnic of Milan | Derudi U.,Aviometal Spa
International Journal of Microstructure and Materials Properties | Year: 2010

The SAE AMS 2772 standard prescribes the possibility of achieving the T7X condition of a 7075 aluminium alloy, starting from the T6 condition and super-imposing successive artificial ageing, with no repetition of solution and quench. The latter is mainly used for mechanical applications of the alloy, due to the wider availability in the market of such a condition. The aim of this work is to investigate the mechanical strengths and the stress corrosion cracking (SCC) behaviour of 7075 aluminium alloy plates, by varying the ageing steps. The T7X condition is achieved starting from a solution treated and quenched (W) condition and from a T6 condition, following different ageing steps according to the standard. The following results have been compared with those obtained with T6 condition and discussed by varying the experimental conditions. Moreover, the effect of each ageing step has been investigated both with mechanical and SCC tests. Copyright © 2010 Inderscience Enterprises Ltd.

Loading Aviometal Spa collaborators
Loading Aviometal Spa collaborators