ca me turlupine cette anodisation rouge des jantes !
sic these de Mr Alejandro
"The earliest studies that reports on nanoporous anodic alumina (NAA) date back to the
first decades of the 20th century and mainly focus on protective and decorative
purposes. Numerous patents were taken out over the years. In 1923, Bengough and
Stuart patented an electrochemical method for protecting aluminium (Al) foil and its
alloys from corrosion [1]. Carboni discovered a colouring method for Al foils in 1936,
which combined sequential anodization and alternating current using an acid solution
and a metal salt solution as electrolytes, respectively [2].
In 1953, Keller characterized the nanoporous anodic alumina structure for the first time
by electron microscopy. In his work, he describes the NAA structure as hexagonally
arranged arrays of nanometric pores, in which the interpore distance (i.e. the distance
between the centres of adjacent pores) is directly proportional to the anodization
voltage [3]. This work became the base for subsequent studies on the chemical and
physical properties of NAA. In this regard, the first theoretical models about the
formation mechanisms of both barrier and porous types of aluminium oxide (Al2O3)
were developed by Diggle in 1968 [4]. Subsequently, Thompson and Wood made good
use of new characterization techniques such as microtome sectioning and transmission
electron microscopy to provide a better understanding of the growth mechanism of
NAA, anion incorporation and water content in the NAA structure [5-9]. "
donc sur ta randonneuse qui sent les annees 50 a plein nez , ca aurait pu etre original
mais ce qui me gene c est que c est la premiere fois que je vois des jantes anodisées sur un velo du genre.
On connait les jantes de couleur - ou plus exactement avec bandes de couleurs sur des rochet mais c etait peint si je ne m abuse
le profil de la jante pourrait etre un indice - il fait plutot plus tardif mais ca n est pas un element parfaitement probant
Le fait qu il n y ai pas d oeillet peut aussi laisser penser qu elles sont relativement anciennes quand meme
ca serait bien de les demonter pour voir les ecrous de rayons et la forme interne
ca permettrait d avancer dans l analuse !
Elle est absolument magnifique !!!!
